Performance Tests and

Adjustments Manual

HP 8568B Spectrum Analyzer

HEWLETT

PACKARD

HP Part No. 08568-90118

Printed in USA September 1993

. . .

III

Caution The caution sign denotes a hazard. It calls attention to a procedure which, if not correctly performed or adhered to, could result in damage to or destruction of the instrument. Do not proceed beyond a caution sign until the indicated conditions are fully understood and met.

Warning The warning sign denotes a hazard. It calls attention to a procedure which, if not correctly performed or adhered to, could result in injury or loss of life. Do not proceed beyond a warning sign until the indicated conditions are fully understood and met.

General Safety

Considerations

Warning Before this instrument is switched on, make sure it has been properly grounded through the protective conductor of the ac power cable to a socket outlet provided with protective earth contact.

Any interruption of the protective (grounding) conductor, inside or outside the instrument, or disconnection of the protective earth terminal can result in personal injury.

Warning There are many points in the instrument which can, if contacted, cause personal injury. Be extremely careful.

Any adjustments or service procedures that require operation of the instrument with protective covers removed should be performed only by trained service personnel.

Caution Before this instrument is switched on, make sure its primary power circuitry has been adapted to the voltage of the ac power source.

Failure to set the ac power input to the correct voltage could cause damage to the instrument when the ac power cable is plugged in.

V

HP 85680B RF Section RF Section service information.

Troubleshooting and

Repair Manual

HP 85662A IF-Display IF-Display Section service information.

Section

Troubleshooting and

Repair Manual

vi

Contents

4.Resolution Bandwidth Accuracy Test . . . . . . 2-13

5.Resolution Bandwidth Selectivity Test . . . . . . 2-15

6.Resolution Bandwidth Switching Uncertainty Test 2-18

7.Input Attenuator Switching Uncertainty Test . . 2-20

8.Frequency Response Test . . . . . . . . . . . . 2-22

9.RF Gain Uncertainty Test . . . . . . . . . . . . 2-31

10.IF Gain Uncertainty Test . . . . . . . . . . . 2-33

11.Log Scale Switching Uncertainty Test . . . . . 2-39

12.Amplitude Fidelity Test . . . . . . . . . . . . 2-41

13.Average Noise Level Test . . . . . . . . . . . 2-45

14.Residual Responses Test . . . . . . . . . . . . 2-47

15.Spurious Responses Test . . . . . . . . . . . . 2-49

16.Residual FM Test . . . . . . . . . . . . . . . 2-56

17.Line-Related Sidebands Tests . . . . . . . . . 2-60

18.Calibrator Amplitude Accuracy Test . . . . . . 2-62

19.Fast Sweep Time Accuracy Test (~20 ms) . . . . 2-63

20.1st LO Output Amplitude Test . . . . . . . . . 2-66

21.Frequency Reference Error Test . . . . . . . . 2-67 ???Ihble 2-19. Performance Test Record . . . . . . . . . . 2-69 Test 1. Center Frequency Readout Accuracy Test . . . 2-70 Test 2. Frequency Span Accuracy Test . . . . . . . . 2-71

Test 3. Sweep Time Accuracy . . . . . . . . . . . . 2-72 Test 4. Resolution Bandwidth Accuracy . . . . . . . 2-73 Test 5. Resolution Bandwidth Selectivity . . . . . . . 2-74 Test 6. Resolution Bandwidth Switching Uncertainty

Test . . . . . . . . . . . . . . . . . . . . . . 2-75 Test 7. Input Attenuator Switching Uncertainty Test . 2-76 Test 8. Frequency Response Test . . . . . . . . . . 2-77 Test 9. RF Gain Uncertainty Test . . . . . . . . . . 2-78 Test 10. IF Gain Uncertainty Test . . . . . . . . . . 2-79

C o n t e n t s - l

Test 11. Log Scale Switching Uncertainty Test . . . . 2-82 Test 12. Amplitude Fidelity Test . . . . . . . . . . . 2-83 Test 13. Average Noise Level Test . . . . . . . . . . 2-84 Test 14. Residual Responses Test . . . . . . . . . . . 2-85 Test 15. Spurious Responses Test . . . . . . . . . . 2-86 Test 16. Residual FM Test . . . . . . . . . . . . . . 2-87 Test 17. Line-Related Sidebands Test . . . . . . . . . 2-88 Test 18. Calibrator Amplitude Accuracy Test . . . . . 2-89 Test 19. Fast Sweep Time Accuracy Test (~20 ms) . . 2-90 Test 20. 1st LO Output Amplitude Test . . . . . . . . 2-91 Test 21. Frequency Reference Error Test . . . . . . . 2-92

3.Adjustments

1.Low-Voltage Power Supply Adjustments . . . . . . 3-25

2.High-Voltage Adjustment (SN 3001A and Below) . . 3-29

2.High-Voltage Adjustment (SN 3004A and Above) . . 3-39

3.Preliminary Display Adjustments (SN 3001A and

4.Final Display Adjustments (SN 3001A and Below) . 3-59

4.Final Display Adjustments (SN 3004A and Above) . 3-61

5.Log Amplifier Adjustments . . . . . . . . . . . . 3-65

6.Video Processor Adjustments . . . . . . . . . . . 3-69

7.3 MHz Bandwidth Filter Adjustments . . . . . . . 3-72

8.21.4 MHz Bandwidth Filter Adjustments . . . . . 3-77

9.3 dB Bandwidth Adjustments . . . . . . . . . . 3-84

10.Step Gain and 18.4 MHz Local Oscillator

Adjustments . . . . . . . . . . . . . . . . . . 3-87

11.Down/Up Converter Adjustments . . . . . . . . 3-92

12.Time Base Adjustment (SN 2840A and Below, also

32 17AO5568 and Above) . . . . . . . . . . . . . 3-95

12.Time Base Adjustment (SN 2848A to 3217A05567) 3-99

13.20 MHz Reference Adjustments . . . . . . . . . 3-103

14.249 MHz Phase Lock Oscillator Adjustments . . . 3-107

15.275 MHz Phase Lock Oscillator Adjustment . . . . 3-110

16.Second IF Amplifier and Third Converter

Adjustment . . . . . . . . . . . . . . . . . . . 3-112

17.Pilot Second IF Amplifier Adjustments . . . . . . 3-116

18.Frequency Control Adjustments . . . . . . . . . 3-119

19.Second Converter Adjustments . . . . . . . . . 3-123

20.50 MHz Voltage-Tuned Oscillator Adjustments . . 3-130

21. Slope Compensation Adjustments . . . . . . . . 3-133

22.Comb Generator Adjustments . . . . . . . . . . 3-136

23.Analog-To-Digital Converter Adjustments . . . . . 3-139

24.Track and Hold Adjustments . . . . . . . . . . . 3-142

25.Digital Storage Display Adjustments . . . . . . . 3-145 Low-Noise DC Supply . . . . . . . . . . . . . . . . 3-150

Contents-2

Crystal Filter Bypass Network Configuration . . . . . 3-151

Contents-3

Figures

Contents-4

Contents-5

Contents-6

Contents-7

lhbles

Contents-E

1

General Information

G e n e r a l I n f o r m a t i o n l-1

Operation Verification A high confidence level in the instrument???s operation can be achieved by running only the Operation Verification Program, since it tests most of the instrument???s specifications. It is recommended that the Operation Verification Program be used for incoming inspection and after repairs, since it requires much less time and test equipment.

A description of the program can be found in the Installation and Verification manual.

l-2 G e n e r a l I n f o r m a t i o n

G e n e r a l I n f o r m a t i o n 1 - 3

???Ihble l-l. Recommended Test Equipment (2 of 5)

l-4 G e n e r a l I n f o r m a t i o n

l-6 G e n e r a l I n f o r m a t i o n

???Ihble l-l. Recommended Test Equipment (5 of 5)

* Part of Service Accessories

G e n e r a l I n f o r m a t i o n l-7

Figure l-l. Service Accessories, HP Part Number 08568-60001

l-8 G e n e r a l I n f o r m a t i o n

2

Performance Tksts

If the results of a performance test are marginally within specification, go to the Adjustments section of this manual and perform the related adjustment procedures. When an adjustment is directly related to a performance test, the adjustment procedure is referenced under RELATED ADJUSTMENT in the performance test.

Calibration Cycle This instrument requires periodic verification of performance. The instrument should have a complete verification of specifications at least every six months.

P e r f o r m a n c e T e s t s 2-l

Equipment Required Equipment required for the manual performance tests and adjustments is listed in ???Ihble 2-1, Recommended Test Equipment, at the beginning of this manual. Any equipment that satisfies the critical specifications given in the list may be substituted for the recommended model.

Test Record The Operation Verification Program provides a detailed test record when a printer is used with the controller. If manual performance tests are done, results of the performance tests may be tabulated in the HP 8568B Performance Test Record at the end of this section. The HP 8568B Performance Test Record lists all of the tested specifications and the acceptable ranges for the measurement values obtained during the tests.

Note Allow l/2-hour warm-up time for the HP 8568B before beginning the Performance Tests.

able 2-1. Performance Test Cross-Reference

2 - 2 P e r f o r m a n c e T e s t s

1. Center Frequency Readout Accuracy Test

1. Center

Frequency Readout

Accuracy ???I&t

Related Adjustments Frequency Control Adjustments

Time Base Adjustment

Step Gain and 18.4 MHz Local Oscillator Adjustments

50 MHz Voltage-Tuned Oscillator Adjustments

Specification (uncorrected)

f2% of frequency span + frequency reference error x tune frequency +30% of resolution bandwidth setting + 10 Hz) in AUTO resolution bandwidth after adjusting FREQ ZERO at stabilized temperature.

Description A synthesized signal source that is phase-locked to a known frequency standard is used to input a signal to the analyzer. The frequency readout of the analyzer is compared to the actual input frequency

for several different frequency settings over the analyzer???s range. The signal source is phase-locked to a standard known to be as accurate as the analyzer???s internal frequency reference to minimize the ???frequency reference error x center frequency??? term of the specification.

SYNTHESIZED

SHEEPER

SIONAL

INPUT 2

ADAPTER

CABLE ASSENBLY

Figure 2-1. Center Frequency Accuracy Test Setup

P e r f o r m a n c e T e s t s 2-3

1. Center Frequency Readout Accuracy Test

Equipment Synthesized Sweeper . . . . . . . . . HP8340A Frequency Standard . 10 MHz standard, accy within + 1 part in lOlo,

e.g. HP 5061A

Adapter, Type N (m) to SMA (f) . . . HP1250-1250 61 cm (24 in.) Cable Assembly, SMA Male Connectors HP 5061-1086

Procedure 1. Connect CAL OUTPUT to SIGNAL INPUT 2.

2 . Press [INSTR PRESET), @ on the analyzer.

3 . Adjust FREQ ZERO for a maximum amplitude trace.

4 . Press (1tds-r~ PRESET).

5 . Set the synthesized sweeper for a 100.000 MHz signal at a level of approximately 0 dBm.

6 . Connect equipment as shown in Figure 2-l.

7 . Set analyzer ~CENTER FREQUENCY) and [FREQUENCY SPAN) and synthesized sweeper frequency according to Table 2-2. At each setting, press [PEAK SEARCH).~~) to center the signal. Adjust CREFERENCE LEVEL) as necessary to place signal peak at a convenient level.

8.Record the CENTER readout frequency in the table for each setting. The limits for this frequency are given in the table. See Figure 2-2.

Figure 2-2. Center Frequency Readout Error Measurement

2 - 4 Performance Tests

Performance Tests 2 - 5

2. Frequency Span Accuracy lkst

Related Adjustments Frequency Control Adjustments

50 MHz Voltage-Tuned Oscillator Adjustments

Specification

SpanUncertainty

>l MHz f(2% of the actual frequency separation between two points +0.5% of span setting)

51 MHz 445% of the actual frequency separation between two points +0.5% of span setting)

Description Frequency Span accuracy is determined by measuring a frequency at 5% of sweep and then at 95% of sweep. These frequencies correspond

to half a division from each edge of the CRT.

The spans chosen are based on the architecture of the HP 8568B RF hardware:

SYNTHESIZED WEEPER

Figure 2-3. Frequency Span Accuracy Test Setup

2-6 P e r f o r m a n c e T e s t s

Procedure 1. Connect equipment as shown in Figure 2-3.

2.Press QNsTR PRESET] on analyzer.

3.Press [CENTER FREQUENCY] 100 MHz, [FREQUENCY SPAN_) 200 Hz.

4.Connect synthesized sweeper tot spectrum analyzer RF input 2.

5.On synthesized sweeper, select external REFERENCE and key in (jj??? 0 dBm.

6.Press Icw] and key in 99.999 910 MHz.

7.Press MARKER [PEAK SEARCH) on spectrum analyzer and record marker reading under FREQ C of Table 2-3.

8.Set synthesized sweeper frequency to 100.000 090 MHz.

9.Press MARKER [PEAK SEARCH] and record marker reading under FREQ D of Table 2-3.

Performance Tests 2 - 7

2. Frequency Span Accuracy Test

For spans > 1 MHz, the spec is: >*[(.02)(A synth freq) + (.005)(span)]

For spans 2 1 MHz, the spec is: >&[(.05)(A synth freq) + (.005)(span)]

2 - 8 Performance Tests

3. Sweep Time Accuracy Test (220 ms)

3. Sweep Time Accuracy Test (220

ms)

Related Adjustment Frequency Control Adjustments

Specification *lo% for sweep times 5100 seconds &20% for sweep times >lOO seconds

Description Preferred Procedure

This test is for sweep times 220 ms. For faster sweep times, refer to

Fast Sweep Time Accuracy Test (Test 19).

A universal counter is connected to the PENLIFT RECORDER OUTPUT (on the rear panel) of the spectrum analyzer. The counter is used in time interval mode to determine the ???pen down??? (sweep time) interval of the PENLIFT RECORDER OUTPUT. The penlift output voltage level corresponds directly to the sweeping of the analyzer (pen down = OV) and not-sweeping of the analyzer (pen up = 15V). A DVM is used to set the appropriate trigger level for the counter.

Alternate Procedure

Perform this procedure if the equipment for the preferred procedure is unavailable.

Sweep time accuracy for sweep times 220 ms can also be measured using the HP 8568B???s internal frequency counter for a time interval measurement.

SPECTRUM ANALYZER

UNIVERSAL

COUNTER

DIGITAL VOLTMETER

\

Figure 2-4. Sweep Time Accuracy Test Setup

Performance Tests 2 - 9

3. Sweep Time Accuracy Test (220 ms)

Equipment Universal Counter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 5316A Digital Voltmeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3456A

Procedure

Sweep Times 220 ms 1. Connect equipment as shown in Figure 2-4.

2.Press [INSTR PRESET) on the spectrum analyzer.

3.Key in the following settings:

4.Set up the universal counter as follows:

a. Set all front panel keys in ???out??? position. b. Set POWER switch to ON.

c.Set GATE TIME vernier control to 9 o???clock. d. Set SEPXOM A switch to COM A position.

e. Depress T.I. A + B switch (making sure the blue shift key is out).

f. Set Channel A trigger level to trigger on negative slope. g. Set Channel B trigger level to trigger on positive slope. h. Set both Channel A and Channel B ac/dc switches to de.

i.Connect the digital voltmeter to Channel A TRIGGER LEVEL OUT. (Be sure to ground the DVM properly.)

j. Adjust Channel A trigger level to set a DVM voltage reading of 0.3 v.

k. Repeat steps i and j for Channel B.

5.Set analyzer @WEEP TIME) to 20 ms. Allow the universal counter enough time to settle at this sweep time.

2-10 P e r f o r m a n c e T e s t s

3. Sweep Time Accuracy Test (220 ms)

NOTE:PULSE WIDTH APPROXIMATE

Figure 2-5. Penlift Output Signal

6.Note the measured sweep time on the universal counter and record this value in Table 2-5. The measured sweep time should be a value between the minimum and maximum values given in Table 2-5.

7.Repeat steps 5 and 6 for each sweep time setting in Table 2-5.

???Ihble 2-5.

Sweep Time Accuracy, Sweep Times 220 ms

8.Press MARKER (NORMAL].

9.Use @J to place the marker at the second vertical graticule. 10. Press @FiHIFT),[Xi!FF~.

11.Set analyzer [SWEEP TIME) to 20 s. Allow the universal counter enough time to settle at this sweep time.

12.Note the measured sweep time on the universal counter and

record this value in Table 2-6. The measured sweep time should be a value between the minimum and maximum values given in Table 2-6.

13. Repeat steps 11 and 12 for 200 s sweep time.

P e r f o r m a n c e T e s t s 2-11

3. Sweep Time Accuracy Test (220 ms)

???Ihble 2-6.

Sweep Time Accuracy, Sweep Times 220 s

2 - 1 2 P e r f o r m a n c e T e s t s

Related Adjustment 3-dB Bandwidth Adjustments

Specification &20%, 3 MHz

+lO%, 3 kHz to 1 MHz

&20% 10 Hz to 1 kHz

30 kHz and 100 kHz bandwidth accuracy figures apply only with 190% Relative Humidity, < 40??C.

Description The 3 dB bandwidth for each resolution bandwidth setting is measured with the MARKER function to determine bandwidth

accuracy. The CAL OUTPUT is used for a stable signal source.

Equipment None Required

Procedure 1. Press [INSTR PRESET).

2.Connect CAL OUTPUT to SIGNAL INPUT 2.

3.Key in spectrum analyzer setting as follows:

(CENTER FREQUENCY) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 MHZ

4.Press SCALE LIN pushbutton. Press csHIFT],[my (resolution bandwidth).

5.Adjust [REFERENCE LEVEL] to position peak of signal trace at reference level (top) graticule line. Press SWEEP [SINGLE).

6.Press MARKER [ml and place marker at peak of signal trace with DATA knob. Press MARKER In] and position movable marker 3 dB down from the stationary marker on the positive-going edge of the signal trace (the MARKER A amplitude readout should be -3.00 dB ho.05 dB). It may be necessary to press SWEEP ICONT) and adjust [CENTER FREQUENCY) to center trace on screen.

7.Press MARKER (ZJ and position movable marker 3 dB down from the signal peak on the negative going edge of the trace (the MARKER A amplitude readout should be .OO dB f0.05 dB). The 3 dB bandwidth is given by the MARKER A frequency readout (see Figure 2-6). Record this value in Table 2-8.

P e r f o r m a n c e T e s t s 2-13

4. Resolution Bandwidth Accuracy Test

Figure 2-6. Resolution Bandwidth Measurement

8.Vary spectrum analyzer settings according to ???fable 2-8. Measure the 3 dB bandwidth for each resolution bandwidth setting by the procedure of steps 6 and 7 and record the value in ???Ihble 2-8. The measured bandwidth should fall between the limits shown in the table.

???Ihble 2-8. Bandwidth Accuracy

2 - 1 4 P e r f o r m a n c e T e s t s

5.Resolution Bandwidth Selectivity Test

6.Read the 60 dB bandwidth for the 3 MHz resolution bandwidth setting from the MARKER A frequency readout (see Figure 2-7) and record the value in Table 2-9.

7.Vary spectrum analyzer settings according to Table 2-9. Measure the 60 dB bandwidth for each resolution bandwidth setting by the

procedure of steps 4 through 6 and record the value in ???fable 2-9.

8.Record the 3 dB bandwidths from Table 2-8 in Table 2-9.

9.Calculate the bandwidth selectivity for each setting by dividing the 60 dB bandwidth by the 3 dB bandwidth. The bandwidth ratios should be less than the maximum values shown in

???fable 2-9.

10.The 60 dB bandwidth for the 10 Hz resolution bandwidth setting should be less than 100 Hz.

Figure 2-7. 60 dB Bandwidth Measurement

2 - 1 6 P e r f o r m a n c e T e s t s

5. Resolution Bandwidth Selectivity Test

???lhble 2-9. Resolution Bandwidth Selectivity

P e r f o r m a n c e T e s t s 2 - 1 7

Related Adjustments 3 MHz Bandwidth Filter Adjustments

21.4 MHz Bandwidth Filter Adjustments Down/Up Converter

Adjustments

Specification (uncorrected; referenced to 1 MHz bandwidth; 20 - 30??C after 1 hour warm-up) k2.0 dB, 10 Hz bandwidth

f0.8 dB, 30 Hz bandwidth *0.5 dB, 100 Hz to 1 MHz bandwidth

fl.O dB, 3 MHz bandwidth 30 kHz and 100 kHz bandwidth switching uncertainty figures only applicable 190% Relative Humidity

Description The CAL OUTPUT signal is applied to the input of the spectrum analyzer. The deviation in peak amplitude of the signal trace is then measured as each resolution bandwidth filter is switched in.

Equipment None Required

4 . Press LOG (ENTER dB/bIvj and key in 1 dB. Press MARKER

[PEAK SEARCH) a.

5 . Press m,@J

6 . Key in settings according to Table 2-10. Press MARKER

[PEAK SEARCH] at each setting, then read the amplitude deviation from the MARKER A readout at the upper right of the display (see Figure 2-8). The allowable deviation for each resolution bandwidth setting is shown in the table.

2 - 1 8 P e r f o r m a n c e T e s t s

6. Resolution Bandwidth Switching Uncertainty Test

Figure 2-8. Bandwidth Switching Uncertainty Measurement

???Ihble 2-10. Bandwidth Switching Uncertainty

Performance Tests 2-l 9

7.Input Attenuator Switching Uncertainty Test

6.Press MARKER CPEAK SEARCH),(KJ

7.Set [~~J???JREFERENCE LEVEL], and frequency synthesizer

amplitude according to Table 2-l 1. At each setting, press MARKER (PEAK SEARCH) and record the deviation from the 10 dB setting from the MARKER A amplitude readout (see Figure 2-10). The deviation should not exceed *l.O dB at any setting.

HKR A 0 Hz

Performance Tests 2 - 21

8. Frequency

Response Test

Related Adjustment Slope Compensation Adjustment

Specification SIGNAL INPUT 1

~tl.5 dB, 100 Hz to 1.5 GHz

*I dB, 100 Hz to 500 MHz

SIGNAL INPUT 2

fl dB, 100 kHz to 1.5 GHz

Description Frequency response at both analyzer inputs is tested by slowly sweeping a flat signal source over the frequency range and observing the peak-to-peak variation in trace amplitude. The test is divided into three parts. First, the response is tested from 20 MHz to 1.5 GHz

with a power-meter-leveled synthesized sweeper. Next, a frequency synthesizer is used to check the response from 100 kHz to 20 MHz. Finally, SIGNAL INPUT 1 is tested from 100 Hz to 100 kHz with a function generator.

SPECTRUM ANALYZER

SYNTHESIZED SWEEPER

POWER METER

R E C O R D E R

O U T P U T

I G N A L

N P U T

.\ I

ADA,PT,ERS

POWER SENSOR

O P T I O N 0 0 1 . A D D 5 0 OHMS/75 O H M P A D A N D A D A P T E R

gb12b

Figure 2-11. Frequency Response Test Setup (20 MHz to 1.5 GHz)

2 - 22 Performance Tests

8. Frequency Response Test

Note Equipment listed is for three test setups, Figure 2-11, Figure 2-13, and Figure 2-15.

Equipment Synthesized Sweeper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8340A Power Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..HP436A Power Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8482A Frequency Synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3335A Function Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3312A Power Splitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 11667A Adapter, Type N (m) to BNC (f) . . . . . . . . . . . . . . . . . . . . . . . . HP 1250-0780 Adapter, Type N (m) to BNC (m) . . . . . . . . . . . . . . . . . . . . . . . HP 1250-0082 Adapter, Type N (m) to Type N (m) . . . . . . . . . . . . . . . . . . . . HP 1250-0778 Adapter, Type N (m) to SMA (f) . . . . . . . . . . . . . . . . . . . . . . . . HP 1250-1250 Adapter, APC-3.5 (f) to APC-3.5 (f) . . . . . . . . . . . . . . . . . . . . HP 1250-1749 Cable, SMA Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 5061-5458

Additional Equipment for Option 001:

5OfY700 Minimum Loss Pad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 11852A Adapter, Type N (f) to BNC (m) (7561) . . . . . . . . . . . . . . . . . . HP 1250-1534

Procedure

20 MHz to 1.5 GHz 1. Press ~NSTR PRESET) on spectrum analyzer and synthesized sweeper.

3.Connect equipment as shown in Figure 2-l 1. The RECORDER OUTPUT on rear panel of power meter is connected to LEVELING EXT INPUT of the synthesized sweeper. One output arm of the power splitter is connected directly to SIGNAL INPUT 2 of the spectrum analyzer via the N-to-N adapter. The power sensor connects directly to the other splitter output.

4.Depress RANGE HOLD button on power meter.

5.Select METER leveling on synthesized sweeper.

6.Key in the following spectrum analyzer settings:

[CENTER FREQUENCY) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 MHZ

P e r f o r m a n c e T e s t s 2.23

8. Frequency Response Test

7.Adjust POWER LEVEL on synthesized sweeper (using data knob) to place peak of 20 MHz signal near reference level (top) graticule line.

8.Press [ENTER dB/mv], 1 dB on spectrum analyzer. Adjust POWER LEVEL on synthesized sweeper to position peak of signal 2 divisions below the reference level line.

9 . Key in the following spectrum analyzer settings:

START FREQ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20.MHz

10.Press TRACE A [MAX) on the analyzer.

11.Press SWEEP SINGLE on the synthesized sweeper.

DL -.B

dBm

,I

Figure 2-12. Frequency Response Measurement (20 MHz to 1.5 GHz)

12.Press DISPLAY LINE [ENTER) on the spectrum analyzer. Use the Display Line to measure the maximum and minimum points on the trace. Record measurements below.

SIGNAL INPUT 2

(20 MHz to 1.5 GHz)

MaximumdBm

MinimumdBm

13.To check SIGNAL INPUT 1, use the type N male to BNC male adapter to connect the power splitter directly to SIGNAL INPUT 1.

Option 001: Use HP 11852A Minimum Loss Pad and adapters between splitter and spectrum analyzer input.

14. Press [INSTR PRESET) on spectrum analyzer, then activate SIGNAL INPUT 1 with the pushbutton.

2 - 24 Performance Tests

8. Frequency Response Test

Option 001: Set [REFERENCE LEVEL] TO -6.0 dBm.

15.Repeat steps 6 through 11. Press DISPLAY LINE [ENTER) on the spectrum analyzer. Use the Display Line to measure the maximum and minimum points on the trace. Record measurements below.

SIGNAL INPUT 1

(20 MHz to 1.5 GHz)

MaximumdBm

MinimumdBm

16.Press MARKER (-1 on spectrum analyzer. Set marker to 500 MHz. Press DISPLAY LINE (ENTER] on the spectrum analyzer. Use the Display Line to measure the maximum and minimum points between 20 MHz and 500 MHz. Record measurements below.

SIGNAL INPUT 1

(20 MHz to 500 GHz)

MaximumdBm

MinimumdBm

100 kHz to 20 MHz 17. Set the frequency synthesizer controls as follows:

FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 MHz

SWEEP WIDTH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19.9 MHz

AMPLITUDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 2 dBm

(Option 001: + 4 dBm)

18.Connect equipment as shown in Figure 2-13. The output of the frequency synthesizer should be connected to SIGNAL INPUT 1.

Option 001: Use HP 11852 Minimum Loss Pad and adapters.

SPECTRUM ANALYZER

FREQUENCY SYNTHESIZER

II

l-fADAPTER

OPTIOW 001: MO 80 oHMa/ 78 ON88 PM AW AIDAPTUII

Figure 2-13. Frequency Response Test Setup (100 kHz to 20 MHz)

19. Press ~NSTR PRESET) on the spectrum analyzer. Activate SIGNAL INPUT 1 with the pushbutton.

20. Key in the following spectrum analyzer settings:

Performance Tests 2 - 25

8. Frequency Response Test

25.After completion of sweep, press DISPLAY LINE (j?KiK] on the spectrum analyzer. Use the Display Line to measure the maximum and minimum points on the trace. Record the measurements below.

SIGNAL INPUT 1 (100 kHz to 20 MHz)

MaximumdBm

MinimumdBm

26. Measure and record signal level at start of trace (100 kHz).

SIGNAL INPUT 1 (100 kHz)

dBm

27.Connect output of frequency synthesizer to SIGNAL INPUT 2. Activate this input with the pushbutton.

Option 001. Do not use HP 11852A Minimum Loss Pad. Set frequency synthesizer output amplitude to -2 dBm.

28.Press TRACE A CCLEAR-WRITE) and DISPLAY LINE (OFF) on spectrum analyzer.

29.Set frequency synthesizer FREQUENCY to 20 MHz. Set spectrum

analyzer (CENTER FREQUENCY_) to 20 MHz, and (FREQUENCY SPAN) to

1MHz.

30.Repeat steps 22 through 24.

31.After completion of sweep, press DISPLAY LINE [ENTER] on the spectrum analyzer. Use the Display Line to measure the maximum and minimum points on the trace. Record the measurements below.

SIGNAL INPUT 2

(100 kHz to 20 MHz)

MaximumdBm

MinimumdBm

Figure 2-15.

Frequency Response Test Setup (100 Hz to 100 k=)

P e r f o r m a n c e T e s t s 2-27

8. Frequency Response Test

100Hzto 100 kHz 32. Press (INSTR PRESET) on the spectrum analyzer. Activate SIGNAL INPUT 1.

33. Key in the following spectrum analyzer settings:

34.Connect equipment as shown in Figure 2-15 with function generator to SIGNAL INPUT 1.

35.Set the function generator controls as follows:

LINE . . . . . . . . . . . . . . . . . . .. . . . . . .. . . . . . . . . . . . . . . . . . . . ON

RANGE Hz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 K

FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -

OFFSET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CAL (button in)

AMPLITUDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 V

AMPLITUDE VERNIER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . midrange

SYM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CAL

TRIGGER PHASE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FREE RUN

MODULATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . all out

MODULATION RANGE Hz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I

M O D U L A T I O N R A N G E H z V E R N I E R . . . . . . . f u l l y C C W

MODULATION SYM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CAL

Percent Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. ..fullyCW

36.Adjust function generator FREQUENCY to place signal between the last two graticule lines (right side) on the signal analyzer display.

37.Adjust AMPLITUDE VERNIER on the function generator until the peak of the signal is at the reference graticule line on the spectrum analyzer display.

38.Press LOG CENTER dB/DIv_) 1 dB on the spectrum analyzer. Press DISPLAY LINE [ENTER] and set the Display Line to the level recorded for 100 kHz in step 25.

39.Adjust function generator AMPLITUDE VERNIER to place peak of signal at the Display Line.

40.Adjust FREQUENCY on the function generator to position the signal trace at the right edge of the spectrum analyzer display (last graticule line).

41.Press MODULATION SWP on the function generator and allow the function generator to make at least two complete sweeps. Press

TRACE A [MAX HOLD). Allow the function generator to make one complete sweep. After completion of the sweep, press TRACE A

m).

2.28 P e r f o r m a n c e T e s t s

8. Frequency Response Test

42.Press DISPLAY LINE [ENTER] on the spectrum analyzer. Use the Display Line to measure the maximum and minimum points on the trace. (Disregard LO Feedthrough at 1 kHz.) Record the measurements below.

SIGNAL INPUT 1

(1 kHz to 100 kHz)

MaximumdBm

MinimumdBm

43.Set Display Line to peak of trace at 1 kHz.

44.Key in the following spectrum analyzer settings:

TRACE A (CLEAR-WRITE)

. . . . . . . . . . . . . . . . . . . . .l kHz 1 kHz iO0 Hz

45. Set function generator controls as follows:

RANGE Hz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 (button) FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 MODULATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..all out

46.Adjust function generator FREQUENCY as necessary to place signal near center graticule line and adjust AMPLITUDE VERNIER to place peak of signal at Display Line.

47.Key in the following spectrum analyzer settings:

FREQUENCY SPAN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 Hz

&TT!, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Hz

48. Set (CF STEP SIZE] to 100 Hz. Step spectrum analyzer

( C E N T E R FFIEQUENCY] from 1 kHz to 100 Hz with a, while setting function generator FREQUENCY to match spectrum analyzer center frequency at each step. Record level-at each setting.

P e r f o r m a n c e T e s t s 2 - 2 9

8. Frequency Response Test

49.For each input, subtract the lowest minimum level (greatest negative) from the highest maximum (least negative) measurement recorded in steps indicated. The result should not exceed 2 dB.

SIGNAL INPUT 1

100 Hz to 500 MHz (from steps 16, 25, 42, or 48)

SIGNAL INPUT 2

100 kHz to 1.5 GHz (from steps 12 or 31)

50.Subtract the lowest minimum level (greatest negative) from the highest maximum (least negative) measurement recorded in steps indicated. The result should not exceed 3 dB.

SIGNAL INPUT 1

100 Hz to 1.5 GHz (from steps 15, 16, 25, 42, or 48)

2.30 P e r f o r m a n c e T e s t s

9. RF Gain Uncertainty Test

h

Figure 2-16. RF Gain Uncertainty Measurement

2 - 3 2 P e r f o r m a n c e T e s t s

10. IF Gain Uncertainty Test

10. IF Gain

Uncertainty Test

Related Adjustments Step Gain and 18.4 MHz Local Oscillator Adjustments

21.4 MHz Bandwidth Filter Adjustments

Specification Assuming the internal calibration signal is used to calibrate the reference level at -10 dBm and the input attenuator is fixed at 10 dB, any changes in reference level from the -10 dB setting will contribute to IF gain uncertainty as shown:

-56.0 dBm to -129.9 dBm Res BW 230 Hz, f1.0 dB; Res BW = 10 Hz, f2.0 dB

Description The IF gain steps are tested over the entire range from 0 dBm to -129.9 dBm using an RF substitution method. The 10 dB, 2 dB, and 0.1 dB steps are compared against a calibrated signal source provided by an HP 3335A Frequency Synthesizer.

Figure 2-17. IF Gain Uncertainty Test Setup

Performance Tests 2 - 33

10. IF Gain Uncertainty Test

Equipment Frequency Synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3335A Adapter, Type N (m) to BNC (f) . . . . . . . . . . . . . . . . . . . . . . . . HP 1250-0780

Procedure 1. Press ( INSTR pfwm-).

2.Connect CAL OUTPUT to SIGNAL INPUT.

3.Press Cm] 8. Adjust AMPTD CAL for a MARKER amplitude of -10.00 dBm 50.02 dB.

4.Press (1~~733 PRESET).

10 dB Gain Steps 5. Set the frequency synthesizer for an output frequency of 20.0010 MHz and an output power level of -2.0 dBm. Set the amplitude increment for 10 dB steps.

6.Connect the equipment as shown in Figure 2-17.

7.Key in analyzer settings as follows:

CCENTER FREQUENCY) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20.001 MHZ

CFREQUENCY SPAN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 kHz

8 Press MARKER (PEAK SEARCH).~~) or adjust (CENTER FREQUENCY) to center signal trace on display.

10.Press MARKER [PEAK SEARCH),

11.Press (SHIFT),(m]I to permit extended reference level settings.

12.Set the analyzer (REFERENCE LEVEL],(VIDEO], and frequency synthesizer amplitude according to Table 2-12 settings. (Use the frequency synthesizer @J for 10 dB steps.) At each setting, note the MKR A amplitude displayed in the upper right corner of the analyzer display (deviation from the 0 dB reference setting) and record it in the table. See Figure 2-18.

Note After measurement at the (REFERENCE LEVEL) = -70 dBm setting, press [SHIFT),(ENTER dB/DIvP as indicated in ???lhble 2-12.

2 - 34 Performance Tests

10. IF Gain Uncertainty Test

???Ihble 2-12. IF Gain Uncertainty, 10 dB Steps

Figure 2-18. IF Gain Uncertainty Measurement

Performance Tests 2 - 35

10. IF Gain Uncertainty Test

2 dB Gain Steps 13. Press QNSTR pREsETj,(jRECALL) 7.

14.Set [REFERENCE LEVEL] to -1.9 dBm.

15.Press MARKER (OFF). Set CVlDEo] to 100 Hz.

16.Set the frequency synthesizer for an output power level of -3.9 dBm. Set the amplitude increment for 2 dB steps.

17.Press MARKER [PEAK SEARCH),@

18.Set the analyzer CREFERENCE LEVEL) and the frequency synthesizer amplitude according to ???Iable 2-13. At each setting, note the MKR A amplitude and record it in the table.

???lhble 2-13. IF Gain Uncertainty, 2 dB Steps

LREFERENCE LEVEL) Frequency Deviation

CdBm) Synthesizer (MARKER A

Amplitude ???Amplitude

YKRAE Hz

1 m/

Figure 2-19. IF Gain Uncertainty Measurement (2 dB)

2 - 36 Performance Tests

10. IF Gain Uncertainty Test

0.1dB Gain Steps 19. Set [REFERENCE LEVEL) to 0 dB.

20.Set the frequency synthesizer for an output power level of -2.00 dBm. Set the amplitude increment for 0.1 dB steps.

21.Press MARKER [PEAK SEARCH),@.

22.Set the analyzer and the frequency synthesizer amplitude according to lkble 2-14. At each setting, note the MKR A amplitude and record it in the table.

23.Find the largest positive deviation and the largest negative

deviation for reference level settings from 0 dBm to -70 dBm in Table 2-12. Also, find the largest positive and negative deviations for the last five settings in the table.

AB

Reference Level Range: 0 to -70 dBm -80 to -120 dBm

24.Find the largest positive and negative deviations in ???lkble 2-13 and Yhble 2-14:

Performance Tests 2 - 37

10. IF Gain Uncertainty Test

???Ihble 2-14. IF Gain Uncertainty, 0.1 dB Steps

25.The sum of the positive deviations recorded in A, C, and D should not exceed 0.6 dB.

26.The sum of the negative deviations recorded in A, C, and D should not be less than -0.6 dB.

27.The sum of the positive deviations recorded in A, B, C, and D should not exceed 1.0 dB.

28.The sum of the negative deviations recorded in A, B, C, and D should not exceed - 1 .O dB.

2 . 3 8 P e r f o r m a n c e T e s t s

11. Log Scale Switching Uncertainty Test

b

2 dB/

Figure 2-20. Log Scale Switching Uncertainty Measurement

able 2-15. Log Scale Switching Uncertainty

2-40 P e r f o r m a n c e T e s t s

Incremental

ho.1 dB/dB over 0 to 80 dB display Cumulative

3 MHz to 30 Hz Resolution Bandwidth

<kl.O dB max over 0 to 80 dB display (20 - 30??C). 5% 1.5 dB max over 0 to 90 dB display

Linear:

f3% of Reference Level for top 9-l/2 divisions of display

Description Amplitude fidelity in log and linear modes is tested by decreasing the signal level to the spectrum analyzer in 10 dB steps with a calibrated signal source and measuring the displayed amplitude change with the analyzer???s MARKER A function.

SIGNAL ANALYZER

SYNTHESIZERf LEVEL

GENERA OR

ADAPTER

?

Figure 2-21. Amplitude Fidelity Test Setup

P e r f o r m a n c e T e s t s 2-41

12. Amplitude Fidelity Test

Equipment Frequency Synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3335A Adapter, Type N (m) to BNC (f) . . . . . . . . . . . . . . . . . . . . . HP 1250-0780

Procedure Log Fidelity

1. Set the frequency synthesizer for an output frequency of 20.000 MHz and an output power level of + 10 dBm. Set the amplitude increment for 10 dB steps.

2.Connect equipment as shown in Figure 2-21.

3.Press ~NSTR PRESET) on the analyzer. Key in analyzer settings as follows:

[ C E N T E R F R E Q U E N C Y ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 MHZ FREQUENCY S P A N ] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50 kHz

CREFERENCE LEVEL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + 10 dBm

4.Press MARKER SPEAK SEARCHJ@~K~GTJ~MKR + REF LVL) to

center the signal on the display.

5.Key in the following analyzer settings:

FREQUENCY SPAN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O Hz

[&Xi, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Hz

6.Press MARKER A. Step the frequency synthesizer output amplitude from + 10 dBm to -80 dBm in 10 dB steps, noting the MARKER A amplitude (a negative value) at each step and

recording it in column 2 of ???fable 2-16. Allow several sweeps after each step for the video filtered trace to reach its final amplitude (see Figure 2-22).

7.Subtract the value in column 1 from the value in column 2 for each setting to find the fidelity error.

2 - 42 Performance Tests

12. Amplitude Fidelity Test

8.The fidelity error for amplitude steps from -10 dB to -80 dB should be <& 1.0 dB.

9.The fidelity error at the -90 dB setting should be s&l.5 dB.

YKR A

REF 9.7 d&n ATTEN 20 dB

4J

10 d0/

Figure 2-22. Amplitude Fidelity Measurement

Linear Fidelity 10. Key in analyzer settings as follows:

FREQUENCY SPAN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .I MHz

[M, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 MHz

11.Set the frequency synthesizer for an output power level of + 10 dBm.

12.Press SCALE LIN pushbutton. Press MARKER

CPEAK SEARCHJ[MKR) to center the signal on the display.

13.Set (FREQUENCY SPAN) to 0 Hz and [VlDEo] to 1 Hz. Press @???iYiF),[XF6-~ (resolution bandwidth), MARKER a.

14.Decrease frequency synthesizer output amplitude by 10 dB steps, noting the MARKER A amplitude and recording it in column 2 of

???Ikble 2-17.

Performance Tests 2 - 43

12. Amplitude Fidelity Test

???Ihble 2-17. Linear Amplitude Fidelity

2 - 44 Performance Tests

13. Average Noise Level Test

13. Average Noise

Level Tkst

Specification c-135 dBm for frequencies >I MHz, c-112 dBm for frequencies <l MHz but >500 Hz with 10 Hz resolution bandwidth, 0 dB input attenuation, 1 Hz video filter.

Option 001: c-129 dBm for frequencies >l MHz, c-106 dBm for frequencies 51 MHz but >500 Hz with 10 Hz resolution bandwidth, 0 dB input attenuation, 1 Hz video filter (SIGNAL INPUT 1 only).

Description The average noise level is checked by observing the displayed noise level at several frequencies with no input signal applied.

Equipment 50 Ohm Termination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .HP 11593A

Procedure 1. Press (~NsTR PRESET].

2.Connect CAL OUTPUT to SIGNAL INPUT 2.

3.Press m @. Adjust AMPTD CAL for a MARKER amplitude of -10.00 dBm 50.02 dB.

4.Press ~NSTR PRESET].

5.Disconnect CAL OUTPUT from analyzer. Terminate SIGNAL INPUT 2 with a 509 coaxial termination.

6.Key in spectrum analyzer settings as follows:

7.Press SWEEP (SINGLE] and wait for completion of the sweep.

8.Press DISPLAY LINE [ENTER). Using DATA knob, place display line at the apparent average amplitude of the noise trace (see Figure 2-23).

Performance Tests 2 - 45

13. Average Noise Level Test

Figure 2-23. Average Noise Level Measurement

9.Read the average noise level from the DISPLAY LINE readout. The value should be c-112 dBm.

dBm

10.Change [CENTER FREQUENCY) to 1.001 MHz. Follow the procedure to steps 7 through 9 to determine the average noise level. The value should be c-135 dBm.

dBm

11.Change (-CENTER FREQUENCY) to 1501 Mhz. Follow the procedure of steps 7 through 9 to determine the average noise level. The value should be <- 135 dBm.

dBm

2 - 46 Performance Tests

14. Residual Responses Test

14. Residual

Responses Test

Specification c-105 dBm for frequencies >500 Hz with 0 dB input attenuation (no signal present at input) Option 100:

c-99 dBm for frequencies >500 Hz with 0 dB input attenuation (SIGNAL INPUT 1 only).

Option 400:

c-95 dBm for frequencies >500 Hz with 0 dB input attenuation. c-105 dBm for frequencies >2.5 kHz with 0 dB input attenuation.

Description The spectrum analyzer is checked for residual responses across its frequency range with no signal applied to the input and 0 dB input attenuation.

Equipment 50 Ohm Termination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 11593A

Procedure 1. Press (INSTR PRESET].

2.Connect CAL OUTPUT to SIGNAL INPUT 2.

3.Press IRECALL) @J Adjust AMPTD CAL for a MARKER amplitude of -10.00 dbm f0.02 dB.

4.Press QNSTR PRESET).

5.Disconnect CAL OUTPUT from analyzer. Terminate SIGNAL INPUT 2 with a 50 ohm coaxial termination.

6.Key in control settings as follows:

7.Press DISPLAY LINE CENTER_) and key in -105 dBm.

8.Reduce [RESBW) or [VlDEOBW), if necessary, for a margin of at least 4 dB between the noise trace and the display line (refer to Figure 2-24). Do not reduce either bandwidth to less than 300 Hz.

Note This test will require approximately 30 minutes to complete using the settings given in step 6. If the resolution bandwidth or video bandwidth are further reduced, a full band check of residual responses will take up to 15 hours to complete

Performance Tests 2 - 47

14. Residual Responses Test

Figure 2-24. Residual Responses Measurement

9.Press SWEEP [SINGLE_) and wait for completion of sweep. Look for any residual responses at or above the display line. If a residual is suspected, press SWEEP CRINGLE) again and see if the response persists. A residual will persist on repeated sweeps, but a noise peak will not. Any residual responses must be c-105 dBm.

Option 400:

Any residual 500 Hz to 2.5 kHz must be c-95 dBm; any residuals >2.5 kHz must be c-105 dBm

10.If a response appears marginal, do the following to determine whether or not it exceeds the specification.

a.Press ISAVE_) 0.

b.Press MARKER [NORMAL) and place the marker on the peak of the response in question.

c.Press MARKER Ijj), then activate SWEEP m.

d.Reduce [FREQUENCY SPAN] to 1 MHz or less. The amplitude of the response should be c-105 dBm (below the display line).

e.Press (RECALL] (iJ to resume the search for residuals.

11.Step [CENTER FREQUENCY) to 1510 MHz with @) checking for residual responses at each step by the procedure of steps 9 and

10.There should be no residual responses at or above the display line below 1500 MHz.

Maximum Residual Response

dBm

MHz

2 - 46 Performance Tests

15. Spurious Responses Test

15. Spurious

Responses Test

Related Adjustment Second Converter Adjustments

Specification For total signal power of c-40 dBm at the input mixer of the analyzer, all image and out-of-band mixing responses, harmonic and intermodulation distortion products are >75 dB below the total signal power for input signals 10 Mhz to 1500 MHz; >70 dB below the total signal power for input signals 100 Hz to 10 MHz.

Second Harmonic Distortion

For a signal -30 dBm at the mixer and 210 MHz, second harmonic distortion is >70 dB down; 60 dB down for signals ~10 MHz.

Third Order Intermodulation Distortion

For two signals each -30 dB at the mixer, third-order intermodulation products are:

Description Harmonic distortion (second and third) is tested using a signal source and a low-pass filter. The LPF insures that the harmonics measured are generated by the spectrum analyzer and not by the signal source.

Spurious responses due to image frequencies, out-of-band mixing, and intermodulation distortion are measured by applying signals from two separate sources to the spectrum analyzer input.

P e r f o r m a n c e T e s t s 2-49

15. Spurious Responses Test

SPECTRUM ANALYZER

SYNTHESIZED SMEEPEA

10 DB

ATTENUATOR

300 MHZ LPF

J

Figure 2-25. Harmonic Distortion Test Setup

Note Equipment listed is for two test setups, Figure 2-25 and Figure 2-26.

Procedure Harmonic Distortion

1.Connect equipment as shown in Figure 2-25.

2.On the spectrum analyzer, press [INSTR PRESET). Set the controls of the spectrum analyzer as follows:

3. On the synthesized sweeper, key in ~NSTR PRESET], Icw) 280 MHz,

( P O W E R L E V E L ) - 10 dBm.

4.On the spectrum analyzer, key in DISPLAY LINE CENTER] -90 dBm, MARKER [PEAK SEARCH] to position a marker on the peak of the displayed 280 MHz signal.

5.On the synthesized sweeper, press ~POWER LEVEL] and use the ENTRY knob to adjust the amplitude of the displayed 280 MHz

2-50 P e r f o r m a n c e T e s t s

15. Spurious Responses Test

signal for a marker indication of -20.00 dBm (-30.0 dBm at the input mixer with 10 dBm of input attenuation).

6 On the spectrum analyzer, key in MARKER @,

CCENTER FREQUENCY) 560 MHz, MARKER CPEAK SEARCH) to position a second marker on the peak of the second harmonic distortion product of the 280 MHz input signal. The response should be below the display line (>70 dB below the input signal level).

7.On the synthesized sweeper, key in ~POWER LEVEL) ato decrease the amplitude of the 280 MHz signal by 10 dB.

8.On the spectrum analyzer, key in MARKER loFF),

CCENTER FREQUENCY) 280 MHz, [REFERENCE LEVEL) -30 dBm, DISPLAY LINE [ENTER] -105 dBm, MARKER CPEAK SEARCH) to position a marker on the peak of the displayed 280 MHz signal.

9.On the synthesized sweeper, press [POWER LEVEL] and use the ENTRY knob to adjust the amplitude of the displayed 280 MHz signal for a marker indication of -30.00 dBm (-40.0 dBm at the input mixer with 10 dBm of input attenuation).

10.On the spectrum analyzer, key in MARKER a],

[CENTER FREQUENCY) 840 MHz, MARKER [PEAK SEARCH) to position a second marker on the peak of the third harmonic distortion product of the 280 MHz input signal. The response should be below the display line (>75 dB below the input signal level).

Performance Tests 2 - 51

Figure 2-26. Intermodulation Distortion Test Setup

11.Connect equipment as shown in Figure 2-26.

12.Set the controls of the spectrum analyzer as follows:

CENTER FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . 29.5 MHz

FREQUENCY SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 MHz

REFERENCE LEVEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -20 dBm

DISPLAY LINE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OFF

13.On the synthesized sweeper, key in [cw 30 MHz, [POWER LEVEL], -4 dBm and use the ENTRY knob to position the peak of the displayed 30 MHz signal at the top CRT graticule line.

14.On the frequency synthesizer, key in [FREQUENCY) 29 MHz,

(AMPLITUDE) -4 dBm. Readjust the signal amplitude as necessary to position the peak of the displayed 29 MHz signal at the top CRT graticule line.

15. Set the controls of the spectrum analyzer as follows:

CENTER FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 MHz

FREQUENCY SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 500 Hz

16.On the spectrum analyzer, key in DISPLAY LINE (ENTER) -100 dBm, MARKER [PEAK SEARCH) to position a marker on the peak of the displayed 29 MHz signal.

17.On the frequency synthesizer, adjust the signal amplitude for a marker indication of -20.00 dBm.

18.On the spectrum analyzer, key in [CENTER FREQUENCY) 30 MHz, MARKER [PEAK SEARCH) to position a marker on the peak of the displayed 30 MHz signal.

19.On the synthesized sweeper, adjust the signal power level for a marker indication of -20.00 dBm.

2 - 5 2 P e r f o r m a n c e T e s t s

15. Spurious Responses Test

Note If unable to locate intermodulation distortion products, temporarily increase output power level of frequency synthesizer and synthesized sweeper by + 10 dB. Return the output power level of both

signal sources to the previous settings before making distortion measurements.

20. On the spectrum analyzer, key in MARKER [n),

[CENTER FREQUENCY) 31 MHz, MARKER [PEAK SEARCH) to position

a marker at the peak of the 31 MHz third-order intermodulation product. The response should be below the display line (GO dB below the input signals).

TO1 Distortion (1 MHz separation @ 30 MHz) dBm

21.On the spectrum analyzer, key in [CENTER FREQUENCY) 28 MHz, MARKER [PEAK SEARCH] to position a marker at the peak of the 28 MHz third-order intermodulation product. The response should be below the display line (>80 dB below the input signals).

TO1 Distortion (1 MHz separation @ 30 MHz) dBm

Performance Tests 2 - 53

15. Spurious Responses Test

24.On the frequency synthesizer, readjust the signal amplitude as necessary to position the peak of the displayed 29.99 MHz signal at the top CRT graticule line.

25.On the spectrum analyzer, key in MARKER @,

(CENTER FREQUENCY) 30.01 MHz, MARKER (PEAK SEARCH) to position a second marker at the peak of the 30.01 MHz third-order intermodulation product. The response should be below the display line (>70 dB below the input signals).

TO1 Distortion (10 kHz separation @ 30 MHz) dBm

26.On the spectrum analyzer, key in [CENTER FREQUENCY) 29.98 MHz, MARKER [PEAK SEARCH) to position a second marker at the peak of the 29.98 MHz third-order intermodulation product. The response should be below the display line (>70 dB below the input signals).

TO1 Distortion (10 kHz separation @ 30 MHz) dBm

27.On the synthesized sweeper, press (POWER LEVEL] and decrease the amplitude of the 30 MHz signal by 13.0 dB from the current setting.

28.On the frequency synthesizer, key in [FREQUENCY] 29 MHz, (AMPLITUDE] and then decrease the amplitude of the 29 MHz signal by 13.0 dB from the current setting.

29.Set the controls of the spectrum analyzer as follows:

CENTER FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 MHz

FREQUENCY SPAN . . . . . . . . . . . . . . . . . . . . . . . . . ,500 Hz

REFERENCE LEVEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -33 dBm

MARKER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OFF

30.On the spectrum analyzer, key in DISPLAY LINE [ml -105 dBm, MARKER CPEAK SEARCH) to position a marker on the peak of the displayed 29 MHz signal.

31.On the frequency synthesizer, adjust the signal amplitude for a marker indication of -33.0 dBm.

32.On the spectrum analyzer, key in CCENTER FREQUENCY) 30 MHz, MARKER [PEAK SEARCH) to position a marker on the peak of the displayed 30 MHz signal.

33.On the synthesized sweeper, adjust the signal power level for a marker indication of -33.0 dBm (total signal power of -40 dBm at the input mixer with 10 dB of input attenuation).

34.On the spectrum analyzer, key in MARKER a,

[CENTER FREQUENCY) 1 MHZ, MARKER [PEAK SEARCH] to position

a second marker at the peak of the 1 MHz second-order intermodulation distortion product. The response should be below the display line (>75 dB below the total input power).

SO1 Distortion (1 MHz separation @ 30 MHz) dBm

2 - 5 4 P e r f o r m a n c e T e s t s

15. Spurious Responses Test

35.On the spectrum analyzer, key in [CENTER FREQUENCY] 59 MHz, MARKER [PEAK SEARCH) to position a second marker at the peak of the 59 MHz second-order intermodulation distortion product. The response should be below the display line (>75 dB below the total input power).

SO1 Distortion (1 MHz separation @ 30 MHz) dBm

Performance Tests 2 - 55

16. Residual FM

Test

Specification <3 Hz peak-to-peak in 110 s; frequency span ~100 kHz, resolution bandwidth 530 Hz, video bandwidth 530 Hz.

Description The spectrum analyzer CAL OUTPUT is used to supply a stable 20 MHz signal to the analyzer. The analyzer is tuned in zero span to a point on the 30 Hz bandwidth response for which the slope of the response is known from direct measurement. The residual FM is then slope detected over a 10 second interval, yielding a trace whose peak-to-peak excursion is proportional to the residual FM.

Equipment None Required

Procedure 1. Press (~N~TR PRESET).

2.Connect CAL OUTPUT to SIGNAL INPUT 2.

3.Press (RECALL) 8 and adjust AMPTD CAL for a MARKER amplitude of -10.00 dBm ho.02 dB.

4.Press CRECALL) 9 and adjust FREQ ZERO for a maximum amplitude trace.

5.Set PREFERENCE LEVEL) to -10 dBm. Adjust FREQ ZERO counterclockwise until trace is at the center graticule line.

6.Set ~FREQUENCY SPAN) to 100 Hz. Press SWEEP CSINGLE) and wait for completion of the sweep.

7.Press MARKER Cm), and place marker 1 division above the center graticule line on the negative-going side of the trace. Press MARKER In] and set the movable marker 1 division below the center graticule line. See Figure 2-28.

2 - 5 6 P e r f o r m a n c e T e s t s

16. Residual FM Test

hr RF -I... L 1u

Figure 2-28. Bandwidth Filter Slope Measurement

8.Compute the detection slope of the 30 Hz filter between the markers by dividing the MARKER A amplitude by the MARKER A frequency:

filter slope = MARKER A amplitude/MARKER Afrequency = dB/Hz

9.Press SWEEP [CONT),(mj IOFF).

10.Change FREQUENCY SPAN] to 0 Hz. Readjust FREQ ZERO, if necessary, to position the trace at the center graticule line. The amplitude variations of the trace (see Figure 2-29) represent the analyzer residual FM.

P e r f o r m a n c e T e s t s 2-57

16. Residual FM Test

Figure 2-29. Slope Detected Residual FM

11.Press SWEEP CRINGLE) and wait for completion of the sweep.

12.Press MARKER [PEAK SEARCH_). Press DISPLAY LINE (m??? and position the display line at the lowest point on the trace.

Figure 2-30. Peak-to-Peak Amplitude Measurement

2 - 5 8 P e r f o r m a n c e T e s t s

16. Residual FM Test

13.Press MARKER Ia] and position movable marker at the lowest point on the trace (see Figure 2-30). Read the MARKER A amplitude from the display and record its absolute value.

14.Divide the peak-to-peak amplitude by the slope computed in step 8 to obtain the residual FM:

p-p amplitude/filter slope = residual FM

= residual FM

The residual FM should be less than 3 Hz.

15.Press ~NSTR PRESET].

16.Press Cm] 9 and adjust FREQ ZERO for a maximum amplitude trace.

Performance Tests 2 - 59

2-60 P e r f o r m a n c e T e s t s

17. Line-Related Sidebands Tests

Figure 2-31. Line Related Sidebands Measurement

O p t i o n 4 0 0 1. Press ~NSTR PRESET]. Connect CAL OUTPUT to SIGNAL INPUT 2.

2.Press (ml 8 and adjust AMPTD CAL for a MARKER amplitude of -10. 00 dBm ??? tO.02 dB.

3.Press ONSTR PRESET).

4.Key in the following analyzer settings:

6.Press (SHIFT) [VlDEo] G, SWEEP (-1, 10 cm/Iv to initiate video averaging of 10 sweeps. Wait for completion of sweeps.

7.Press MARKER SPEAK SEARCH],@ and position movable marker at the peak of each line related sideband (400 Hz, 800 Hz, and 1200 Hz). The MARKER A amplitude for each sideband should be c-75 dB.

Performance Tests 2 - 61

18. Calibrator

Amplitude

Accuracy Test

Related Adjustment 20 MHz Reference Adjustments

Specification -10 dBm f0.3 dB

Description The output level of the calibrator signal is measured with a power meter.

SPECTRUW ANILYZER

Figure 2-32. Calibrator Amplitude Accuracy Test Setup

Equipment Power Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 436A Power Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8482A

Adapter, Type N (f) to BNC (m) . . . . . . . . . . . . . . . . . . . . . . . . HP 1250-0077

Procedure 1. Connect equipment as shown in Figure 2-32.

2.Measure output level of the CAL OUTPUT signal. The value should be -10.0 dBm ho.3 dB.

dBm

2 - 62 Performance Tests

19. Fast Sweep Time Accuracy Test (~20 ms)

19. Fast Sweep

Time Accuracy

Test (430 ms)

Related Adjustment None

Specification &lo% for sweep times 5100 seconds

Description The triangular wave output of a function generator is used to modulate a 500 MHz signal which is applied to the spectrum analyzer SIGNAL INPUT. The signal is demodulated in the zero span mode to display the triangular waveform. Sweep time accuracy for sweep times ~20 ms is tested by checking the spacing of the signal peaks on the displayed waveform.

SPECTRUM ANALYZER

SYNTHESIZED SWEEPER

Procedure 1. Connect equipment as shown in Figure 2-33.

2.Press QNSTR PRESET) on spectrum analyzer.

3.Key in analyzer settings as follows:

4.Set synthesized sweeper for an output frequency of 500 MHz and an output power level of -10 dBm.

Performance Tests 2 - 63

19.Fast Sweep Time Accuracy Test (~20 ms)

5.Press MARKER (PEAK SEARCHJ@~EFZF),~.

6.Set [FREQUENCY SPAN) to 0 Hz, (j-1 to 3 MHz, [VlDEoBW) to 3 MHz, and press TRIGGER Cm].

7.Set synthesized sweeper for an amplitude-modulated output.

8.Set function generator controls as follows:

9.Key in (SWEEP TIME] 5 ms and set function generator for a counter reading of 2.00 f0.02 kHz.

10.Adjust spectrum analyzer TRIGGER LEVEL to place a peak of the triangular waveform on the first graticule from the left edge of the CRT display as a reference. (Adjust function generator amplitude, if necessary, to provide a signal large enough to produce a stable display). The fifth peak from the reference should be within ~l~0.5 division of the sixth graticule from the left edge of the display (see Figure 2-34).

11.Using sweep times and function generator frequencies in

Table 2-18, check sweep time accuracy for sweep times ~20 ms by procedure of step 10.

Figure 2-34. Fast Sweep Time Measurement (~20 ms)

2 - 64 Performance Tests

19. Fast Sweep Time Accuracy Test (~20 ms)

Performance Tests 2 - 65

20. 1st LO Output Amplitude Test

Specification >+4 dBm from 2.0 GHz to 3.7 GHz

Description The power level at the 1ST LO OUTPUT connected is measured as the first L.O. is swept over its 2.0 GHz to 3.1 GHz range.

SPECTRUM ANALYZER

POWER METER

Figure 2-35. 1st LO Output Amplitude Test Setup

Equipment Power Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 436A Power Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8482A

Procedure 1. Press (INSTR PRESET].

2.Set [SWEEP TIME) to 100 seconds.

3.Calibrate power meter and sensor. Connect equipment as shown in Figure 2-35.

4.Observe the meter indication as the analyzer makes a complete sweep. The indication should be > + 4 dBm across the full sweep range.

dBm

5. Replace 50 ohm terminator on 1ST LO OUTPUT.

2 - 6 6 P e r f o r m a n c e T e s t s

21. Frequency Reference Error Test

21. Frequency

Reference Error

Test

Related Adjustment Time Base Adjustment

Specification Aging Rate

<l x 10eg/day and ~2.5 x 10m7 year; attained after 30 days warmup from cold start at 25??C.

Temperature Stability

<7 x lo-??? 0??? to 5E9???C. Frequency is within 1 x lo-??? of final stabilized frequency within 30 minutes.

Description The frequency of the spectrum analyzer time base oscillator is measured directly using a frequency counter locked to a frequency reference which has an aging rate less than one-tenth that of the time base specification. After a 30 day warmup period, a frequency measurement is made. The analyzer is left undisturbed for a 24-hour period and a second reading is taken. The frequency change over this 24-hour period must be less than one part in 10???.

Note This test requires that the spectrum analyzer be turned on (not in STANDBY) for a period of 30 days to ensure that the frequency reference attains its aging rate. However, after aging rate is attained, the frequency reference typically attains aging rate again in 72 hours of operation after being off for a period not exceeding 24 hours.

Care must be taken not to disturb the spectrum analyzer during the 24-hour test interval, since the frequency reference is sensitive to shock and vibration. The frequency reference should remain within its attained aging rate if the instrument is left on, the instrument orientation with respect to the earth???s magnetic field is maintained, and the instrument does not sustain any mechanical shock. Frequency changes due to orientation with respect to the earth???s magnetic field and altitude changes will usually be nullified when the instrument

is returned to its original position. Frequency changes due to mechanical shock will usually appear as a fixed frequency error.

The frequency reference is also sensitive to temperature changes; for this reason the ambient temperature near the instrument at the first measurement time and the ambient temperature at the second measurement time should not differ by more than 1??C.

Placing the spectrum analyzer in STANDBY mode turns the instrument off while continuing to provide power for the frequency reference oven, helping to minimize warmup time. However, the frequency reference must be on to attain its aging rate.

Performance Tests 2 - 67

???lhble 2-19. Performance Tkst Record

Performance Tests 2-69

Tkst 1. Center

Frequency Readout

Accuracy Test

Step 8. Center Frequency Readout Error Test Record

2-70 Performance Tests

Test 2. Frequency Span Accuracy Test

???I&t 2. Frequency

Span Accuracy Test

Steps 7, 9, and 11. Wide Span Error

Step 12. Span Error

Note The specification in Table 2-4 was derived using the following formula:

For spans > 1 MHz, the spec is: >&[(.02)(A synth freq) + (.005)(span)]

For spans 5 1 MHz, the spec is: >&[(.05)(A synth freq) + (.005)(span)]

Performance Tests 2-71

Test 3. Sweep

Time Accuracy

Step 6. Sweep Time Accuracy, Sweep Times 220 ms

Step 12. Sweep Time Accuracy, Sweep Times 220 s

21

Step 19. Sweep Time Accuracy, Sweep Times 220 ms (Alternate Procedure)

2-72 Performance Tests

Performance Tests 2-73

Test 5. Resolution

Bandwidth

Selectivity

Steps 7, 8 and 9. Resolution Bandwidth Selectivity

2-74 Performance Tests

Test 6. Resolution Bandwidth Switching Uncertainty Test

lkst 6. Resolution Bandwidth Switching Uncertainty Test

Step 6. Bandwidth Switching Uncertainty

Performance Tests 2-75

Test 7. Input

Attenuator

Switching

Uncertainty Test

2-76 Performance Tests

Test 8. Frequency Response Test

Performance Tests 2-77

Test 9. RF Gain

Uncertainty Test

Step 6. 2nd LO Shift

Min Measured Max

2-78 Performance Tests

Test 10. IF Gain Uncertainty Test

Test 10. IF Gain

Uncertainty Test

Step 12. Step IF Gain Uncertainty, 10 dB Steps

Step 18. IF Gain Uncertainty, 2 dB Steps

Performance Tests 2-79

Test 10. IF Gain Uncertainty Test

Step 22. IF Gain Uncertainty, 0.1 dB Steps

2-80 Performance Tests

Step 24. Recorded deviations from Steps 18 and 22.

26.Sum of negative deviations of A, C, & D -0.6 dB

28.Sum of negative deviations of A, B, C, & D -1.0 dB

Performance Tests 2-81

YLkst 11. Log Scale

Switching

Uncertainty Tkst

Step 6. Log Scale Switching Uncertainty

2-82 Performance Tests

Test 12. Amplitude Fidelity Test

Test 12. Amplitude

Fidelity ???I&t

Step 6. Log Amplitude Fidelity

Step 14. Linear Amplitude Fidelity

Performance Tests 2-83

Test 13. Average

Noise Level Test

2-84 Performance Tests

Test 14. Residual Responses Test

Test 14. Residual

Responses Test

Step 11. Maximum Residual Response

Performance Tests 2-85

Tkst 15. Spurious

Responses Tkst

2-86 Performance Tests

Test 16. Residual FM Test

Test 16. Residual

FM Test

Step 14. Residual FM

IMinIMeasuredIrax]

Performance Tests 2-87

Tkst 17.

Line-Related

Sidebands Test

2-88 Performance Tests

Test 18. Calibrator Amplitude Accuracy Test

Test 18. Calibrator

Amplitude

Accuracy ???I&t

Step 2. CAL OUTPUT Amplitude

Performance Tests 2.89

2.90 Performance Tests

Performance Tests 2-91

Test 21. Frequency

Reference Error

Test

2-92 Performance Tests

3

Adjustments

The adjustment procedures should not be performed as routine maintenance, but only when Performance Tests cannot meet specifications. Before attempting any adjustment, allow the instrument to warm up for one hour. ???lhble 3-1 is a cross reference of Function Adjusted to the related Adjustment procedure. Table 3-2 lists all adjustable components by name, reference designator, and function.

Adjustments 3-1

3-2 Adjustments

???able 3-l. Adjustment Cross Reference

Adjustments 3-3

3-4 Adjustments

For Serial Prefix 3001A and below, see back of table for exceptions to AlA through AlA6.

Adjustments 3-5

???able 3-2. Adjustable Components (continued)

Adjustments 3-7

3-8 Adjustments

Adjustments 3-9

3-10 Adjustments

???lhble 3-2. Adjustable Components (continued)

Adjustments 3-11

???Ihble 3-2. Adjustable Components (continued)

3-12 Adjustments

???Ihble 3-3. Factory-Selected Components

Adjustments 3-13

l???hble 3-3. Factory-Selected Components (continued)

3-14 Adjustments

Adjustments 3-15

3-16 Adjustments

Adjustments 3-17

???able 3-3. Factory-Selected Components (continued)

3-18 Adjustments

???able 3-3. Factory-Selected Components (continued)

Adjustments 3-19

???lkble 3-4. Standard Value Replacement Capacitors

rapaors

Value (pF) 1BP Fart Number CD Value (pF) ZP Fart Number s-

-

3-20 Adjustments

Adjustments 3-21

???Ihble 3-5.

Standard Value Replacement 0.125 Resistors (continued)

Type: Fixed-Film

Range: 10 to 464K Ohms

Wattage: 0.125 at 125??C

To1 e???an fl.O%

Value (0) BP Part Number co Value (!I) ElP Fart Number

-

3-22 Adjustments

Table 3-6. Standard Value Replacement 0.5 Resistors

Resistors

Type: Fixed-Film

Range: 10 to 1.47M Ohms

Wattage: 0.5 at 125???C

To1???ant 31.0%

EIP Fart Number 5 Value (fl) BP Part Number 56 Value (0)-

-

Adjustments 3-23

Ihble 3-6.

Standard Value Replacement 0.5 Resistors

(continued)

Type: Fixed-Film

Range: 10 to 1.47M Ohms

Wattage: 0.5 at 125??C

To1 e*an fl.O%

Value (0) EIP Fart Number CD Value (a) EIP Fart Number

-

3-24 Adjustments

Description The + 15 V supply is adjusted for the IF-display Section, and the +20 V supply is adjusted for the RF Section. All other low-voltage supplies are measured to ensure that they are within tolerance.

SPECTRUM ANALYZER

DIGITAL VOLTMTER

ADAPTER

(+)

Adjustments 3-25

1.Low-Voltage Power Supply Adjustments

4.Connect the DVM to AlA6TP3 on the IF-Display Section. DVM

indication should be + 15.000 fO.O1O V dc. If the voltage is out of tolerance, adjust AlA6R9 + 15 V ADJ for the specified voltage.

, AlA71P2

AlA6DS2

AlA6TP4 5

Figure 3-2.

IF-Display Section Low-Voltage Adjustments (SN 3001A and

Below)

A l A7DS2

AlA7TP3

A lA6DS2

AiA6TP4

t

Figure 3-3.

IF-Display Section Low-Voltage Adjustments (SN 3004A and

Above)

5.Verify that the -15 V indicator AlA6DS2 (yellow LED) is lit.

6.Connect the DVM to AlA6TP4. DVM indication should be

-15.000 f0.050 V dc. The -15 V supply is referenced to the + 15 V supply; therefore, if the -15 V supply is out of tolerance, a circuit malfunction is indicated.

3-26 Adjustments

RF Section 11. The +2OV indicator A24DS2 (yellow LED) should be lit. See Figure 3-4.

A24

V O L T A G EA24R60

R E G U L A T O R +2OV A D J

A24

Figure 3-4. Location of RF Section Low-Voltage Adjustments

12.Connect the DVM to A24TP3 with the ground lead to A24TPl. Adjust A24R60 +2OV ADJ for a DVM indication of +20.000 &O.OlO V dc.

13.The + 15V indicator A24DS4 (yellow LED) should be lit.

14.Connect the DVM to A24TP2. The DVM indication should be

+15.000 ho.050 V dc. The + 15V supply is referenced to the

+2OV supply, therefore, if the + 15V supply is out of tolerance, a circuit malfunction is indicated.

15.The +5V indicator A24DS5 (yellow LED) should be lit.

16.Connect the DVM to A24TP5. The DVM indication should be +5.230 f0.050 V dc. The +5V supply is referenced to the +2OV

Adjustments 3-27

1. Low-Voltage Power Supply Adjustments

supply, therefore, if the +5V supply is out of tolerance, a circuit malfunction is indicated.

17.The -5V indicator A24DS6 (yellow LED) should be lit.

18.Connect the DVM to A24TP7. The DVM indication should be -5.200 ho.050 V de. The -5V supply is referenced to the +2OV supply, therefore, if the -5V supply is out of tolerance, a circuit malfunction is indicated.

19.The -15V indicator A24DS3 (yellow LED) should be lit.

20.Connect the DVM to A24TP4. The DVM indication should be

-15.000 f0.050 V dc. The -15V supply is referenced to the + 20V supply, therefore, if the -15V supply is out of tolerance, a circuit malfunction is indicated.

3-28 Adjustments

Note This procedure should be performed whenever the AlAll High Voltage Multiplier, AlVl CRT, or AlA High Voltage Regulator Assembly is repaired or replaced.

Reference IF-Display Section:

AlA Z-Axis Amplifier

AlA High-Voltage Regulator

AlA f15 V Regulator

AlA + 100 V, +5.2 V Regulator

Description

Warning This procedure is intended for adjustment purposes only. Voltages are present which, if contacted, could cause serious personal injury. Approximately -4000 V dc can be present on the AlA High Voltage assembly even when the ac line cord is disconnected. Do not attempt to remove the AlA High-Voltage Assembly from the instrument. Do not disconnect the CRT???s post-accelerator cable; the CRT can hold a + 18 kV dc charge for several days.

If for any reason the AlA High Voltage Assembly or the post accelerator cable must be removed, refer to ???Discharge Procedure for High Voltage and CRT??? at the end of this adjustment procedure.

A 1OOO:l divider probe is used to measure the CRT cathode voltage. First, the high-voltage probe is calibrated by comparing measurements of the + 100 V dc supply voltage with and without the probe. Any measurement error due to the use of the high-voltage probe is calculated into the adjustment specification of the CRT cathode voltage, which is adjusted with the AlA HV ADJUST control. When the CRT cathode voltage is properly adjusted, the CRT filament voltage will be +4.45 f0.04 V rms measured with CRT beam at cut-off, which is required for maximum CRT life. The filament voltage is referenced to the high-voltage cathode and can only be measured directly with special equipment.

Adjustments 3-29

2. High-Voltage Adjustment (SN 3001A and Below)

DIGITIZING

OSCILLOSCOPE

HI-VOLTAGE

SIGNAL ANALYZER

Figure 3-5. High Voltage Adjustment Setup

Equipment Digital Voltmeter (DVM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .HP 3456A DC High-Voltage Probe (1000: 1 divider) . . . . . . . . . . . . . . . . . . HP 34111A Display Adjustment PC Board (service accessory) . . . . . . .85662-60088 Digitizing Oscilloscope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 54501A 1O:l Divider Probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 10432A Function Generator (2 required) . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3312A

Warning Do not attempt to measure the CRT filament voltage directly. The filament voltage is referenced to the high-voltage cathode and can only be measured safely with a special high-voltage true-rms voltmeter and probe.

1.Set the spectrum analyzer???s LINE switch to STANDBY.

2.Remove the top cover from the IF-Display Section, and connect the equipment as shown in Figure 3-5 and described in the following steps.

3.Set the DVM to the 100 V range, and connect the DVM to AlA7TP3 (+ 100 V). Do not use the high-voltage probe. See

Figure 3-6 for the location of AlA7TP3.

3.30 A d j u s t m e n t s

Adjustments 3-3 1

2. High-Voltage Adjustment (SN 3001A and Below)

12.Connect the high-voltage probe to AlA3TP3. See Figure 3-7 for the location of the test point.

AlA

H,gh V o l t a g e

R e g u lotor

Figure 3-7. Location of Label and Test Point

13.Reconnect ac line cords to both instrument sections. Set the LINE switch to ON.

14.Wait approximately 30 seconds for the dc regulator circuits to stabilize.

15.Adjust AlA6R32 HV ADJ for a DVM indication equal to the calibration factor (calculated in step 8) times the voltage labeled on the top of AlA High-Voltage Regulator (noted in step 11). See Figure 3-6 for the location of the adjustment.

V dc

EXAMPLE:

3-32 Adjustments

Adjustments 3-33

2.High-Voltage Adjustment (SN 3001A and Below)

27.On the oscilloscope press [SHOW].

28.Connect the oscilloscope channel 1 probe to AlA3TP5 using a long probe extension. See Figure 3-7 for the location of AlA3TP5.

29.Reconnect the ac line cords to each instrument section. Adjust the front-panel INTENSITY control fully counter-clockwise, and then set the LINE switch to ON (the INSTR CHECK I LED will light.)

30.Wait approximately 30 seconds for the dc regulator circuits to stabilize again.

31.With the front-panel INTENSITY control fully counter clockwise, adjust AlA2R35 INT LIMIT (clockwise) until a spot is just visible in the lower left corner of the CRT. See Figure 3-8 for the location of the adjustment.

Note The AlA2R35 INT LIMIT adjustment compensates for the variation in beam cut-off voltage of different CRTs and indirectly sets the maximum beam intensity. AlA2R35 INT LIMIT should have enough range to turn the CRT spot on and off. If the spot is always on, decrease the value of AlA2R9. If the spot is always off, increase the value of AlA2R9. Refer to Table 3-3 for the acceptable range of values, and to Table 3-4 for HP part numbers. Refer to Figure 3-8 for the location of AlA2R9.

Figure 3-8. Location of AlA Components

32.Using a non-metallic alignment tool, center the front panel FOCUS control and adjust AlA2R36 ASTIG and AlA3R14 FOCUS LIMIT for a sharp, focused dot on the CRT display.

33.Adjust AlA2R35 INT LIMIT until the dot just disappears.

3-34 Adjustments

2.High-Voltage Adjustment (SN 3001A and Below)

34.On the oscilloscope, adjust the channel 1 offset voltage as

necessary to measure the peak-to-peak CRT cut-off voltage, V,,, at AlA3TP5. See Figure 3-9. This peak-to-peak voltage should be between 45-75 V,.,. Note this voltage for use in step 39.

1 1 0 . 0 V/div offset: 6 0 . 0 0 v

10.00 : 1 dc

1 f 7 5 . 0 0 v

Figure 3-9. CRT Cut-Off Voltage

35.Connect a separate function generator to each of the X and Y inputs of the Display Adjustment Board, as shown in Figure 3-5.

Set the function generators as follows:

36.Adjust AlA2R35 INT LIMIT clockwise until the display is just visible.

37.Adjust AlA4R7 POS, AlA5R7 POS, and if necessary the function generator de offsets for a full-screen illumination.

38.Set the front-panel INTENSITY control fully counter-clockwise, and, if it is not sealed, adjust AlA2R5 INT GAIN fully clockwise. Adjust AlA2R35 INT LIMIT just below the threshold at which the display illumination becomes visible.

Adjustments 3-35

2.High-Voltage Adjustment (SN 3001A and Below)

39.Slowly adjust the front-panel INTENSITY control through its entire range while monitoring the peak-to-peak voltage at AlA3TP5. As the INTENSITY control is turned clockwise, the peak-to-peak voltage at AlA3TP5 will drop. To prevent long-term CRT damage, this voltage should not drop below (V,, - 5O)V,., or 12 VP-,,, whichever is greater. See Figure 3-10. (The value of V,, was recorded in step 34.)

If the front-panel INTENSITY control cannot be set fully clockwise without dropping below this minimum peak-to-peak voltage, then perform the following:

a.Set the INTENSITY control fully counter clockwise.

b.Set the LINE switch to STANDBY.

c.Increase the value of AlA2R9.

d.Return to step 34.

Note Maximum CRT life expectancy is obtained when the peak-to-peak voltage at AlA3TP5 is as large as possible with the INTENSITY control set fully clockwise. The display illumination must fully disappear with the INTENSITY control set fully counter clockwise.

5 0 . 0 uS/dlv

1 f 85.00 v

Figure 3-10. Waveform at AlA3TP5

40.Replace the cover on the AlA High-Voltage Regulator Assembly.

41.The High-Voltage Adjustment is completed. If an AlA2, AlA4, or AlA assembly has been repaired or replaced, perform adjustment procedure 3, ???Preliminary Display Adjustment (SN 3001A and Below)???, and then adjustment procedure 4, ???Final Display Adjustments (SN 3001A and Below)???. If the AlA2,

3-36 Adjustments

Warning Do not handle the AlA High-Voltage Regulator Assembly or AlAll High-Voltage Multiplier until the following high-voltage discharge procedure has been performed.

1.Set the spectrum analyzer???s LINE switch to STANDBY, remove the ac line cords, and remove the AlA High Voltage Regulator safety cover.

Warning With the ac power cord disconnected, voltages are still present which, if contacted, could cause serious personal injury.

Adjustments 3-37

2.High-Voltage Adjustment (SN 3001A and Below)

5.While holding the insulated handle of the screwdriver, touch the

grounded blade to the following connections:

a.Both brown wires going to the rear of the CRT from AlA via cable harness W21.

b.The yellow, blue, and orange wires in the same cable as ???a. ??? above.

c.The top lead of each of the 11 large vertical capacitors on the AlA High-Voltage Regulator Assembly.

6.Connect the jumper wire from chassis ground to the black wire coming from the AlAll High-Voltage Multiplier at the wire???s connection to AlA3Tl.

AlA

H i g h V o l t a g e

,T 1

AlA3TlAIA3

Figure 3-l 1. Discharging the CRT Post-Accelerator Cable

7.Remove all jumper wires. The AlA High-Voltage Regulator, AlAll High-Voltage Multiplier, and AlVl CRT assemblies should now be discharged.

8.A small bracket and screw secure the AlA High-Voltage Regulator Assembly to the AlAlO Display Motherboard Assembly. The bottom cover of the IF-Display Section must be removed to gain access to this screw prior to removal of the AlA High-Voltage Regulator Assembly.

3-38 Adjustments

Description

Warning This procedure is intended for adjustment purposes only. Voltages are present which, if contacted, could cause serious personal injury. Approximately -2400 V dc can be present on the AlA High Voltage Regulator Assembly even when the ac line cord is disconnected. Do not attempt to remove the AlA High-Voltage Regulator Assembly from the instrument. Do not disconnect the CRT???s post-accelerator cable; the CRT can hold a + 9500 V dc charge for several days.

If for any reason the AlA High Voltage Assembly or the post accelerator cable must be removed, refer to ???Discharge Procedure for High Voltage and CRT??? at the end of this adjustment procedure.

A 1OOO:l divider probe is used to measure the CRT cathode voltage. First, the high-voltage probe is calibrated by comparing measurements of the + 120 V dc supply voltage with and without the probe. Any measurement error due to the use of the high-voltage probe is calculated into the adjustment specification of the CRT cathode voltage, which is adjusted with the AlA HV ADJUST control. When the CRT cathode voltage is properly adjusted, the CRT filament voltage will be +6.00 kO.05 V rms measured with CRT beam at cut-off, which is required for maximum CRT life. The filament voltage is referenced to the high-voltage cathode and can only be measured directly with special equipment.

Adjustments 3-39

2. High-Voltage Adjustment (SN 3004A and Above)

Equipment Digital Voltmeter (DVM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .HP 3456A DC High-Voltage Probe (1000: 1 divider) . . . . . . . . . . . . . . . . . . HP 34lllA

High-Voltage

Adjustment Procedure

Warning In the following procedure, it is necessary to probe voltages which, if contacted, could cause serious personal injury. Use a nonmetallic alignment tool when making adjustments. Be extremely careful.

Warning Do not attempt to measure the CRT filament voltage directly. The filament voltage is referenced to the high-voltage cathode and can only be measured safely with a special high-voltage true-rms voltmeter and probe.

1.Set the spectrum analyzer???s LINE switch to STANDBY.

2.Remove the top cover from the IF-Display Section and connect the equipment as shown in Figure 3- 12.

SPECTRUM ANALYZER

Figure 3-12. High Voltage Adjustment Setup

3.Set the DVM to the 1OOV range, and connect the DVM to AlA7TP3 (+ 120V) without the high-voltage probe. See Figure 3-13.

Note The accuracy of the high-voltage probe is specified for a probe connected to a de voltmeter with 10 MO input resistance. HP 3456A and HP 3455A digital voltmeters have a 10 MQ input resistance on the 100 V and 1000 V ranges. All measurements in this procedure should be performed with the DVM manually set to the 100 V range (&OO.OOO on the HP 3456A display).

3-40 Adjustments

2. High-Voltage Adjustment (SN 3004A and Above)

/ AlABOSl

- AlA7TP3

AlA H I G H

V O L T A G E

/ R E G U L A T O R

- AlA6R103

Figure 3-13. Location of High Voltage Adjustments

4.Set the LINE switch to ON. Set the front-panel INTENSITY control fully counterclockwise (CRT beam at cut-off) to prevent possible damage to the CRT.

5.Note the DVM indication at AlA7TP3.

DVM Indication:

6.Connect the high-voltage probe to the DVM, and connect the probe to AlA7TP3.

7.Note the DVM indication.

DVM Indication:

8.Divide the DVM indication in step 7 by the DVM indication in

step 5. This gives the calibration factor needed to compensate for high-voltage probe error.

Calibration Factor:

9.Disconnect the high-voltage probe from AlA7TP3. Set the LINE switch to STANDBY. Remove the ac line cord from both instrument sections.

Warning The MAINS power-on indicator AlASDSl (red LED) should be completely off before proceeding with this procedure. See

Figure 3-13 The indicator will remain lit for several seconds after the ac line cord has been removed, and will go out slowly (the light becomes dimmer until it is completely out).

Adjustments 3-41

2.High-Voltage Adjustment (SN 3004A and Above)

11.Remove the protective cover from the AlA High-Voltage Regulator Assembly. A label should be visible on the AlA3Al High Voltage Assembly. (AlASAl is mounted on the

non-component side of the High-Voltage Regulator Assembly as shown in Figure 3-14.) Record the voltage listed on the label for

use in step 15. In cases where more than one voltage is listed on this label, record the value which is closest to -2400 Vdc.

V dc

Warning With power supplied to the instrument, AlA3TP2A is at a voltage level of approximately -2400 V dc. Be extremely careful.

12.Connect the high-voltage probe to AlA3TP2A. See Figure 3-14 for the location of the test point.

AlA3TP2A

Figure 3-14. Location of AlA Label and Test Point

13.Reconnect ac line cords to both instrument sections. Set the LINE switch to ON.

14.Wait approximately 30 seconds for the de regulator circuits to stabilize.

15.Adjust AlA6R103 HV ADJ for a DVM indication equal to the calibration factor (calculated in step 8) times the voltage labeled on the top of the AlA3Al High-Voltage Assembly (noted in step 11). See Figure 3-13 for the location of the adjustment.

V dc

EXAMPLE:

If the calibration factor calculated in step 8 is 0.00099, and AlASAl is labeled for -2400 V, then adjust AlA6R103 HV ADJ for a DVM indication of:

0.00099 x (-2400 V) = -2.376 V dc

3-42 Adjustments

Adjustments 3-43

2.High-Voltage Adjustment (SN 3004A and Above)

3.Connect one end of a jumper wire (made of insulated wire and

two alligator clips) to the blade of the screwdriver. Connect the other end of the jumper wire to the metal chassis of the IF Display Section. This grounds the screwdriver.

4.Slide the screwdriver???s blade between the CRT and the sheet metal as shown in Figure 3-15. Gently work the tip of the screwdriver under the post-accelerator cable???s rubber shroud. Make sure that the screwdriver???s tip touches the connection between the post accelerator cable and the CRT. You should hear a cracking sound when the cable discharges.

5.Remove the cover from the AlA High-Voltage Regulator assembly.

6.Touch the screwdriver???s tip to the top lead of each of the 11 large vertical capacitors on the AlA High-Voltage Regulator assembly.

7.The AlA High-Voltage Regulator and AlVl CRT assemblies should now be discharged.

G r o u n d i n g

W i r e

Figure 3-15. Discharging the CRT Post-Accelerator Cable

Note A small bracket and screw secure the AlA High-Voltage Regulator Assembly to the AlAlO Display Motherboard Assembly. The bottom cover of the IF-Display Section must be removed to gain access to this screw prior to removal of the AlA High-Voltage Regulator Assembly.

3-44 Adjustments

Equipment Digitizing Oscilloscope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 54501A Pulse/Function Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8116A 1O:l Divider Probe, 10 MW7.5 pF (2 required) . . . . . . . . . . . HP 10432A Display Adjustment PC Board (setice accessory] . . . . . . .85662-60088 Termination, BNC 500 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 11593A

Adjustments 3-45

3. Preliminary Display Adjustments (SN 3001A and Below)

SOQ TEPMNATIC+

PULSE/FUNCTION

GENERATOR

Figure 3-16. Preliminary Display Adjustments Setup

9.Remove the cover over A3 Digital Storage Section and remove A3A2 Intensity Control Assembly. Insert the Display Adjustment PC board (HP part number 85662-60088) into the A3A2 slot. See Figure 3-17 for the location of the A3A2 assembly.

3-46 Adjustments

3. Preliminary Display Adjustments (SN 3001A and Below)

A1A5,

AlA4-

AlA2???

- A3A2

Figure 3-17. Location of AlA2, AlA4, AlA5, and A3A2

~000uu000000u00ur

Figure 3-18. AlA2, AlA4, and AlA Adjustment Locations

10. Set the Pulse/Function Generator controls as follows:

MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . NORM

Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..pulse

Frequency (FRQ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200 kHz

Width(WID) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...250 ns

Amplitude (AMP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.00 V

Offset (OFS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ,000 mV

Il. Connect the output of the Pulse/Function Generator to Jl (X input) on the Display Adjustment PC board in the A3A2 slot as shown in Figure 3-16.

Note The Pulse/Function Generator???s output must be terminated with 50 ohms. Use a BNC tee, a 500 termination, and a BNC female to SMB female adapter. Install the 500 termination as close to the Display Adjustment PC Board as possible.

Adjustments 3-47

3.Preliminary Display Adjustments (SN 3001A and Below)

16.Three waveforms should be displayed on the oscilloscope, as shown in Figure 3-20. The lower composite waveform represents the combined X deflection voltage applied to the CRT. Use the

oscilloscope???s front-panel knob to adjust waveform fl sensitivity for approximately 8 vertical divisions.

r e m o t e l i s t e n

:

Figure 3-20. Composite X Deflection Waveform

17.Adjust AlA4R28 HF GAIN, AlA4Cl0, and AlA4Cll for minimum overshoot and minimum rise and fall times of the composite X deflection waveform.

Note Always adjust AlA4ClO and AlA4Cll in approximately equal amounts. Do not adjust one to its minimum value and the other to its maximum value.

18.Use the oscilloscope Intnv) markers to measure the risetime, falltime, and percent overshoot of the composite X defection waveform. Rise and fall times should both be less than approximately 65 ns between the 10% and 90% points on the waveform. Overshoot should be less than 3% (approximately 0.25 divisions). See Figure 3-2 1.

O V E R S H O O T

O V E R S H O O T

Figure 3-2 1.

Rise and Fall Times and Overshoot Adjustment Waveform

Adjustments 3-49

3.Preliminary Display Adjustments (SN 3001A and Below)

19.Connect the oscilloscope???s channel 1 probe to AlA5El and the channel 4 probe to AlA5E2. See Figure 3-18 for the location of the test points. Connect the output of the pulse/function generator to 52 (Y input) on the Display Adjustment PC board in the A3A2 slot.

20.The Y Deflection Amplifier is identical to the X Deflection Amplifier. Repeat steps 12 through 18 for the Y Deflection Amplifier using R7, R27, R28, ClO, and Cl1 respectively.

25.Connect the output of the Pulse/Function Generator to 53 (Z input) on the Display Adjustment PC Board in the A3A2 slot. Set the board???s switch to the down position.

Note The pulse/function generator???s output must be terminated with 50 ohms. Use a BNC tee, a 5062 termination, and a BNC female to SMB female adapter. Install the 500 termination as close to the Display Adjustment PC Board as possible.

26. Set the pulse/function generator???s controls as follows:

MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . NORM

Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..pulse

Frequency (FRQ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ,200 kHz

Width(WID) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..250ns

Amplitude (AMP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.OOV

Offset (OFS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.OOV

27.Set the spectrum analyzer???s front-panel INTENSITY control fully clockwise. Note the display on the oscilloscope. The pulse should be >55V peak-to-peak.

3-50 Adjustments

3.Preliminary Display Adjustments (SN 3001A and Below)

28.Set the oscilloscope controls as follows:

Press @iK]:

Channel 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . on amplitude scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6.25 V/div

Press @iZZQ.

29.Adjust AlA4R7 X POS and AlA5R7 Y POS to either extreme to position the CRT beam off-screen (to prevent possible damage to the CRT phosphor). If it is not sealed, adjust AlA2R5 INT GAIN fully clockwise.

30.Adjust the spectrum analyzer???s front-panel INTENSITY control for 50V peak-to-peak (8 divisions) as indicated on the oscilloscope. See Figure 3-22.

18 . 0 0 V/div offset: 4 5 . 0 0 v

10.00 : I dc

1 2 5 . 0 0 0 ns3 7 5 . 0 0 0 ns 5 0 . 0 ns/dlv

1 f 50.00 v

Figure 3-22. 5OV,, Signal

31.Adjust AlA2R22 HF GAIN and AIABCIO for minimum overshoot on rise and minimum rise and fall times of the pulse waveform.

32.Use the oscilloscope [ml markers to measure the risetime, falltime, and percent overshoot of the pulse waveform. Rise and falltimes should be less than 50 ns and 90 ns respectively. Overshoot on the rise should be less than 5% (approximately 0.4 divisions).

33.Set the spectrum analyzer???s LINE switch to STANDBY, and center potentiometers AlA4R7 X POSN and AlA5R7 Y POSN.

34.Disconnect the oscilloscope channel 1 probe from the spectrum analyzer. Remove the Display Adjustment PC board from the A3A2 slot, and reinstall the A3A2 Intensity Control Assembly. Replace the A3 Section cover and cables.

35.Perform Adjustment Procedure 4, Final Display Adjustment (SN 3001A and Below).

Adjustments 3-51

Equipment Digitizing Oscilloscope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 54501A Pulse/Function Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8116A

10:1 Divider Probe, 10 MW7.5 pF, (2 required) . . . . . . . . . . . HP 10432A Display Adjustment PC Board (service accessory) . . . . . . .85662-60088 Termination, BNC 500 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 11593A

Adapters:

Adapter, BNC(f) to SMB(f) . . . . . . . . . . . . . . . . . . . . . . . .1250-1236 Adapter, BNC tee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1250-0781

3-52 Adjustments

Adjustments 3-53

3. Preliminary Display Adjustments (SN 3004A and Above)

AlA

A3A2

A3Al

Figure 3-24. Location of AlA and A3A2

Figure 3-25. AlA Adjustment Locations

10. Set the Pulse/Function Generator controls as follows:

MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . NORM

Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..pulse

Frequency (FRQ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ,200 kHz

Width(WID) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...250 ns

Amplitude (AMP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.00 V

Offset (OFS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .O.OOO mV

11.Connect the output of the Pulse/Function Generator to Jl (X input) on the Display Adjustment PC board in the A3A2 slot as shown in Figure 3-23.

Note The pulse/function generator???s output must be terminated with 50 ohms. Use a BNC tee, a 5Ofl termination, and a BNC female to SMB female adapter. Install the 5052 termination as close to the Display Adjustment PC Board as possible.

3-54 Adjustments

3.Preliminary Display Adjustments (SN 3004A and Above)

12.Set the oscilloscope controls as follows:

13.Set the spectrum analyzer???s front-panel INTENSITY control fully counterclockwise, and then set the LINE switch to ON.

14.The X+ deflection and X- deflection waveforms should be

superimposed on the oscilloscope display, as shown in Figure 3-26. If necessary, adjust AlA2R227 X POSN and AlA2R220 X GAIN for a centered display of at least four vertical divisions. See Figure 3-25 for the location of the adjustments.

hf r u n n i n g

1 1 0 . 0 V/div offset: 2 5 . 0 0 V

10.00 : I dc

4 1 0 . 0 V/div offset: 6 0 . 0 0 v 10.00 : I dc

8..

- 1 2 5 . 0 0 0 ns

1 f 25.00 V

Figure 3-26. X + and X- Waveforms

15. Set the oscilloscope controls as follows:

Press [WFORM MATH):

f l . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..on display . . . . . . . . . . . .. .. .. .. .. . .. .. .. . . . . . . . . . . . . . . . . . . .. .. on math . . . . . . . . . . . . . . . .. . . . . . . . . . . channel 1 - channel 4 sensitivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...25.0 Vldiv

16.Three waveforms should be displayed on the oscilloscope, as shown in Figure 3-27. The lower composite waveform represents

Adjustments 3-55

3. Preliminary Display Adjustments (SN 3004A and Above)

the combined X deflection voltage applied to the CRT. Use the oscilloscope???s front-panel knob to adjust waveform fl sensitivity for approximately 8 vertical divisions.

hp r u n n i n g

: 1 2 0 . 0 V/div

o f f s e t : 2 5 . 0 0 V

.I

..:..

:::. .:. ::.:::::.::.:::..

~~~~:~...~I;::r~i~~~-:1.

.:

- 1 2 5 . 0 0 0 ns1 2 5 . 0 0 0 ns3 7 5 . 0 0 0 ns 5 0 . 0 ns/dlv

1 f 25.00 V

Figure 3-27. Composite X Deflection Waveform

17.Adjust AlA2R217 HF GAIN, AlA2C204, and AlA2C209 for minimum overshoot and minimum rise and fall times of the composite X deflection waveform.

Note Always adjust AlA2C204 and AlA2C209 in approximately equal amounts. Do not adjust one to its minimum value and the other to its maximum value.

18.Use the oscilloscope Intnv] markers to measure the risetime, falltime, and percent overshoot of the composite X defection waveform. Rise and fall times should both be less than approximately 65 ns between the 10% and 90% points on the waveform. Overshoot should be less than 3% (approximately 0.25 divisions). See Figure 3-28.

O V E R S H O O T

9 0 %

O V E R S H O O T

Figure 3-28.

Rise and Fall Times and Overshoot Adjustment Waveform

3.56 Adjustments

3.Preliminary Display Adjustments (SN 3004A and Above)

19.Connect the oscilloscope???s channel 1 probe to AlA2TP104 and the channel 4 probe to AlA2TP105. See Figure 3-25 for the location of the test points. Connect the output of the pulse/function generator to 52 (Y input) on the Display Adjustment PC board in the A3A2 slot.

20.The Y Deflection Amplifier is identical to the X Deflection Amplifier. Repeat steps 12 through 18 for the Y Deflection Amplifier using R127, R120, R117, C104, and C109, respectively.

Pulse Response of 21. Disconnect the oscilloscope channel 4 probe from the spectrum

23.Press m, CHANNEL 1 on, more preset probe , and use the front-panel knob to set the probe to lO.OO:l. Press more .

24.Set the oscilloscope controls as follows:

25.Connect the output of the Pulse/Function Generator to 53 (Z input) on the Display Adjustment PC Board in the A3A2 slot. Set the board???s switch to the down position.

Note The pulse/function generator???s output must be terminated with 50 ohms. Use a BNC tee, a 500 termination, and a BNC female to SMB female adapter. Install the 500 termination as close to the Display Adjustment PC Board as possible.

26. Set the Pulse/Function Generator???s controls as follows:

MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . NORM

Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..pulse

Frequency (FRQ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200 kHz

Width (WID) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250 ns

Amplitude (AMP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.OOV

Offset (OFS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.OOV

27.Disconnect the black connector with three wires (8, 98, and 96) from AlA2J5, and set AlA2R319 INT GAIN fully clockwise.

28.Set the spectrum analyzer???s front-panel INTENSITY control fully clockwise. Adjust the oscilloscope trigger level for a stable display. Note the display on the oscilloscope. The pulse should be >55V peak-to-peak.

Adjustments 3.57

3.Preliminary Display Adjustments (SN 3004A and Above)

29.Set the oscilloscope controls as follows:

30.Adjust the spectrum analyzer???s front-panel INTENSITY control for 50V peak-to-peak (8 divisions) as indicated on the oscilloscope. See Figure 3-29.

hf r u n n i n g

1 f 50.00 v

Figure 3-29. 5OV,., Signal

31.Adjust AlA2R308 HF GAIN and AlA2C307 for minimum overshoot on rise and minimum rise and fall times of the pulse waveform.

32.Use the oscilloscope Intav) markers to measure the risetime, falltime, and percent overshoot of the pulse waveform. Rise and falltimes should be less than 50 ns and 90 ns respectively. Overshoot on the rise should be less than 5% (approximately 0.4 divisions).

33.Set the spectrum analyzer???s LINE switch to STANDBY and reconnect the cable to AlA2J5.

34.Disconnect the oscilloscope channel 1 probe from the spectrum analyzer. Remove the Display Adjustment PC board from the A3A2 slot, and reinstall the A3A2 Intensity Control Assembly. Replace the A3 Section cover and cables.

35.Reconnect the black connector with three wires (8, 98, and 96) to AlA2J5, and set AlA2R319 INT GAIN approximately two-thirds clockwise.

36.Perform Adjustment Procedure 4 Final Display Adjustment (SN 3004A and Above).

3-58 Adjustments

Adjustments 3-59

4.Final Display Adjustments (SN 3001A and Below)

5.For best overall focusing of the display, adjust the following

potentiometers in the sequence listed below:

a.AlA3R14 FOCUS LIMIT for best focus of graticule lines (long vectors)

b.AlA2R36 ASTIG

c.AlA2R30 FOCUS GAIN for best focus of annotation (short vectors)

6.Adjust AlA2R31 ORTHO, the front-panel ALIGN control, and AlA2R32 PATT to optimize the orientation and appearance of the rectangular graticule pattern on the CRT display.

7.Repeat steps 4 through 6 as needed to optimize overall display focus and appearance.

AIAZ

Figure 3-30.

Location of Final Display Adjustments on AlA2, AlA4, and AlA

3-60 Adjustments

4. Final Display Adjustments (SN 3004A and Above)

4. Final Display

Adjustments (SN

3004A and Above)

Reference AlAl Keyboard

AlA X, Y, Z Axis Amplifiers

Description This procedure is used to optimize the appearance of the CRT display during routine maintenance or after CRT replacement or minor repairs. First, the display is adjusted for best focus over the full CRT, then the graticule pattern is adjusted for optimum rectangular display.

Equipment Digital Photometer . . . . . . . . . . . . . . . . . . . . . . . . .Tektronix J-16, Option 02 Photometer Probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Tektronix 56503 Photometer interconnect cable . . . . . . . . . . . . . . . Tektronix 012-0414-02 Photometer light occluder . . . . . . . . . . . . . . . . . . . . .Tektronix 016-0305-00

2.Set the photometer probe to NORMAL. Press [POWER_) on the photometer to turn it on and allow 30 minutes warm-up. Zero the photometer according to the manufacturer???s instructions.

3.With the spectrum analyzer???s LINE switch set to STANDBY, set the potentiometers listed in the ???Iable 3-6 as indicated. See Figure 3-32 for the location of the adjustments.

Note In this procedure, do not adjust the following potentiometers and variable capacitors on the AlA X, Y, Z Amplifier Assembly: C104, C109, C204, C209, C307, R117, R217, or R308. These components are adjusted in the factory and in Adjustment Procedure 3, Preliminary Display Adjustments (SN 3004A and Above).

Adjustments 3.61

4. Final Display Adjustments (SN 3004A and Above)

Figure 3-32. Location of Final Display Adjustments on AlA

???Ihble 3-6. Initial Adjustment Positions

4.Set the spectrum analyzer???s LINE switch to ON, and wait at least 5 minutes to allow the CRT and high-voltage circuits to warm up.

5.Set the front panel INTENSITY control fully counterclockwise and adjust AlA2R516 INT LIM until the display is just visable. See Figure 3-32.

6.Set the front-panel INTENSITY control fully clockwise.

7.Adjust AlA2R220 X GAIN, AlA2R227 X POSN, AlA2R120 Y GAIN, and AlA2R127 Y POSN for optimum centering of the

display annotation and graticule pattern.

3-62 Adjustments

Adjustments 3-63

4.Final Display Adjustments (SN 3004A and Above)

17.Adjust AlA2R512 ORTHO and the front-panel ALIGN control to optimize the orientation and appearance of the rectangular graticule pattern on the CRT display.

18.Repeat steps 13 through 17 as needed to optimize overall display focus and appearance.

3-64 Adjustments

Description First, the A4A2 Log Amplifier-Detector ZERO adjustment is checked and adjusted if necessary, then the A4A3 Log Amplifier-Filter is set for center frequency by injecting a signal and adjusting the bandpass filter center adjustment for maximum DVM indication. The bandpass filter amplitude is adjusted by monitoring the output of the filter control line shorted and not shorted to the + 15V supply. Next, log fidelity (gain and offset of the log curve) is adjusted by adjusting the -12 VTV and the PIN diode attenuator. Last, the linear gain step adjustments are performed to set the proper amount of step gain in the linear mode of operation.

S Y N T H E S I Z E R L E V E L

GENERAT 6R

D I G I T A L V O L T M E T E R

S P E C T R U M A N A L Y Z E R ???$,,,

I

Adjustments 3-65

5. Log Amplifier Adjustments

4. Connect DVM to A4AlTPl and DVM ground to the IF casting. Connect the frequency synthesizer to the RF INPUT. Key in CFREQUENCY) 80 MHz and [AMPLITUDE) -86.98 dBm. The frequency synthesizer will now provide a 5OfI load.

Offset Adjustment Check

5.Adjust A4A2R79 ZERO for 0.0000 f0.0005 V dc. See Figure 3-34 for location of adjustment.

A4A2

A4A3

Figure 3-34. Location of Log Amplifier Adjustments

Bandpass Filter Center Adjustment

6.Press LOG (ENTER dB/DIv)

7.Set the frequency synthesizer for 7.6000 MHz at +5.0 dBm output level.

8.Adjust A4A3C55 CTR for maximum DVM indication. See Figure 3-34 for location of adjustment. If A4A3C55 is at an extreme of its adjustment range (fully meshed, maximum capacitance, or unmeshed, minimum capacitance), increase or

decrease value of A4A3C52 and A4A3C53. Refer to ???able 3-3 for range of values.

Note A4A3C52 is a fine adjustment, and A4A3C53 is a coarse adjustment. If A4A3C55 is fully meshed, increase the value of A4A3C52 or A4A3C53.

3.66 Adjustments

5. Log Amplifier Adjustments

Bandpass Filter Amplitude Adjustment

9.Connect one end of a jumper wire to A4A3TP8. Connect the other end of the jumper to A4A3TP7 (+ 15V). Connecting the

jumper to A4A3TP8 first reduces the chance of shorting the + 15V to ground. Note DVM indication.

V dc

10.Remove the short from between A4A3TP7 and A4A3TP8.

11.Adjust A4A3R67 AMPTD for DVM indication the same as that

noted in step 9 f0.0005 V dc. See Figure 3-34 for location of adjustment. If unable to adjust A4A3R67 AMPTD for proper indication, increase or decrease value of A4A3R66. (If A4A3R67 is fully counter-clockwise, increase the value of A4A3R66.)

Refer to Table 3-3 for range of values.

12.Repeat steps 9 through 11 until DVM indication is the same f0.0005 V dc with A4A3TP7 jumpered to A4A3TP8, and with A4A3TP7 and A4A3TP8 not jumpered. Remove the jumper.

-12 VTV and ATTEN Adjustments

13.Press LIN pushbutton.

14.Adjust frequency synthesizer output level for DVM indication of

+1.000 &IO.0002 V dc.

15.Press LOG [ENTER dB/DIV)

16.Wait three minutes for the log assemblies to stabilize.

17.Decrease the frequency synthesizer output level by 50 dB.

18.Adjust A4A2R91 - 12 VTV for DVM indication of + 500 f 1 mV dc. See Figure 3-34 for location of adjustment.

19.Increase the frequency synthesizer output level by 50 dB (to the level of step 14).

20.Adjust A4A2R61 ATTEN for DVM indication of + 1.000 *O.OOOl V

dc. See Figure 3-34 for location of adjustment. If unable to adjust A4A2R61 ATTEN for proper indication, increase or decrease value of A4A2R62. (If A4A2R61 is fully clockwise, increase the value of A4A2R62.) Refer to ???Ihble 3-3 for range of values.

21.Repeat steps 17 through 20, until specifications of steps 18 and 20 are achieved without further adjustment. Because adjustments A4A2R61 and A4A2R91 are interactive, several iterations are needed.

Linear Gain Adjustments

22.Press LIN pushbutton. DVM indication at A4AlTPl should be

+1.000 f0.020 V dc (+ 0.980 to + 1.020 V dc). If indication is not within this range, repeat steps 14 through 21. If indication is within this range, press [*I CENTER dB/div] q. This disables the IF step gains.

Adjustments 3-67

5. Log Amplifier Adjustments

23.Decrease the frequency synthesizer???s output level 10 dB. Press CREFERENCE LEVEL) 0 dBm, and adjust the frequency synthesizer???s output level for a DVM indication of + 1.00 k.001 Vdc.

24.Verify that attenuator is set at 10 dB. Decrease the frequency synthesizer output level by 10 dB. Press [REFERENCE LEVEL] -60 dB.

25.Adjust A4A3R83 LGlO for DVM indication of + 1.000 kO.010 V dc. See Figure 3-34 location of adjustment. If unable to adjust LGlO for proper indication, increase or decrease value of A4A3R54. Refer to Table 3-3 for range of values.

26.Decrease the frequency synthesizer output level by 10 dB.

27.Key in [REFERENCE LEVEL_) -70 dB.

28.Adjust A4A2R14 LG20 for DVM indication of + 1.000 fO.O1O

V dc. See Figure 3-34 for location of adjustment. If unable to adjust LG20 for proper indication, increase or decrease value of A4A2R18. Refer to lkble 3-3 for range of values.

29. Press [INSTR PRESET] to reenable IF Step Gains.

3.66 Adjustments

Adjustments 3-69

6.Video Processor Adjustments

6.Set step attenuator to 120 dB. DVM indication should be 0.000 *0.0005 V dc. (If DVM indication is out of tolerance, adjust A4A2R79 ZERO on the log amplifier-detector board..)

7.Set step attenuator to 0 dB.

8.Key in [Reference LWI) and adjust DATA knob for DVM indication as close to + 1.000 fO.OO1 V dc as possible. (It may be necessary to slightly adjust the front panel AMPTD CAL control to achieve required tolerance.)

9.Connect DVM to A4AlTP2.

10.Adjust A4AlR14 OS for a DVM indication of 0.000 f0.003 Vdc. See Figure 3-36 for the location of the adjustment.

A4A 1

Figure 3-36. Location of Video Processor Adjustments

11.Connect the DVM to A4AlTP3.

12.Set the step attenuator to 120 dB.

13.Adjust A4AlR32 ZERO for a DVM indication of 0.000 rtO.001 Vdc.

14.Set the step attenuator to 0 dB.

15.Adjust A4AlR36 FS for DVM indication of +2.000 f 0.001 V dc.

16.Repeat steps 12 through 15 until specifications of steps 13 and 15 are met.

LOG Offset Adjust

17.Set step attenuator to 40 dB.

18.Key in Cm), (m) I, LOG (ENTER dt3/mv), (SHIFT) [ENTER dB/DIv

q, PREFERENCE L E V E L ] -50 dBm.

19.Connect DVM to A4AlTPl. Record DVM indication. Indication should be approximately +0.500 V dc.

V de

20.Decrease reference level to -60 dBm using the step key.

21.Adjust A4AlR2 LG OS for DVM indication of +O.lOO +O.OOl V dc greater than the DVM indication recorded in step 19. See

Figure 3-36 for location of adjustment.

3-70 Adjustments

6. Video Processor Adjustments

22.Decrease reference level to -70 dBm using the step key.

23.DVM indication should be +0.200 ??? 0.002 V dc greater than the indication recorded in step 19. If not, readjust A4AlR2 LG OS.

24.Decrease reference level to -90 dBm using the step key.

25.DVM indication should be +0.400 f0.004 V dc greater than the indication recorded in step 19. If not, readjust A4AlR2 LG OS.

26.Repeat steps 17 through 25 until the specifications are met.

Adjustments 3-7 1

Figure 3-37. 3 MHz Bandwidth Filter Adjustments Setup

Equipment Frequency Synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . HP3335A Oscilloscope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 545OlA Crystal Filter Bypass Network (???t required) See Figure 3-91 Test Cable: BNC to SMB snap-on . . . . . . . . . . HP 85680-60093

3-72 Adjustments

7. 3 MHz Bandwidth Filter Adjustments

Procedure 1. Position instrument upright as shown in Figure 3-37 and remove top cover.

2. Set LINE switch to ON and press ~NSTR PRESET).

Frequency Zero Check

3.Connect CAL OUTPUT signal to RF INPUT

4.Key in IRECALL) @.

5.Adjust front panel FREQ ZERO control for maximum signal amplitude on the CRT display.

Filter Center and Symmetry Adjustments

6.Key in ~CENTER FREQUENCY) 20 MHz, CFREQUENCY SPAN) 10

kHz, [REsBWI) 1 kHz, and press LIN pushbutton. Press

CREFERENCE LEVEL] and adjust reference level, using step keys and front-panel knob to place signal peak near top CRT graticule line.

7.On the A4A7 assembly, connect crystal filter bypass networks between the pins above C41 SYM, C32 SYM, C23 SYM, and Cl4 SYM.

8.Adjust A4A7C7 CTR for minimum amplitude signal peak. Adjust A4A7C6 SYM for best symmetry of signal. Repeat adjustments to ensure that the signal is nulled and adjusted for best symmetry. See Figure 3-38 for location of adjustments.

A4A7

3 MHz B a n d w i d t h F i l t e r

A4A7

Figure 3-38.

Location of Center, Symmetry, and 10 Hz Amplitude

Adjustments

9. Remove crystal filter bypass network near Cl4 SYM.

Adjustments 3-73

7.3 MHz Bandwidth Filter Adjustments

10.Adjust A4A7C15 CTR for minimum amplitude of signal peak. Adjust A4A7C14 SYM for best symmetry. Repeat adjustments to ensure that the signal is nulled and adjusted for best symmetry. See Figure 3-38 for location of adjustments.

11.Remove crystal filter bypass network near C23 SYM.

12.Adjust A4A7C24 CTR for minimum amplitude of signal peak. Adjust A4A7C23 SYM for best symmetry of signal. Repeat adjustments to ensure that signal is nulled and adjusted for best symmetry. See Figure 3-38 for location of adjustments.

13.Remove crystal filter bypass network near C32 SYM.

14.Adjust A4A7C33 CTR for minimum amplitude of signal peak. Adjust A4A7C32 SYM for best symmetry of signal. Repeat adjustments to ensure that signal is nulled and adjusted for best symmetry. See Figure 3-38 for location of adjustments.

15.Remove crystal filter bypass network near C41 SYM.

16.Adjust A4A7C42 CTR for minimum amplitude of signal peak. Adjust A4A7C41 SYM for best symmetry of signal. Repeat adjustments to ensure that the signal is nulled and adjusted for best symmetry. See Figure 3-38 for location of adjustments.

17.Signal should be centered on center graticule line on CRT display. If signal is not centered, go back to step 3 and repeat adjustments of each filter stage.

Filter Peak Adjust

18.Press (JNSTR PRESET].

19.Key in CSWEEP TIME] 20 ms, [FREQUENCY SPAN) 0 Hz, CREs] 10 Hz,

[R E F E R E N C E L E V E L ) -20 dBm.

20.Set the frequency synthesizer for 21.400 MHz at an amplitude level of -25.0 dBm.

21.Disconnect cable 97 (white/violet) from A4A8Jl and connect output of the frequency synthesizer to A4A8Jl using BNC to SMB snap-on cable.

22.Set the oscilloscope following settings:

Channel 1

amplitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.005 V/div time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...0.2 psldiv mag x . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5 (vertical) . coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..ac probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1O:l

Channel 2

amplitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O.O05V/div coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ac probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1O:l

23.Connect oscilloscope Channel 1 probe to A4A7TP7 (left side of Cl4 SYM) and Channel B probe to A4A7TP5 (left side of C23 SYM).

24.Adjust frequency synthesizer output frequency to peak Channel 1 display.

3-74 Adjustments

7.3 MHz Bandwidth Filter Adjustments

25.Adjust A4A7C13 PK for maximum peak-to-peak signal on Channel 2 display. See Figure 3-39 for location of adjustment. If unable to achieve a ???peak??? in signal amplitude, increase or decrease value of A4A7C12. Refer to Table 3-3 for range of values.

A4A7

3 M H z B a n d w i d t h F i l t e r

Figure 3-39. Location of 3 MHz Peak Adjustments

26.Move Channel 2 probe to A4A7TP3 (left side of C32 SYM).

27.Adjust frequency synthesizer output frequency to peak Channel 1 display.

28. Adjust A4A7C22 PK for maximum peak-to-peak signal on Channel 2 display. See Figure 3-39 for location of adjustment. If unable to achieve a ???peak??? in signal amplitude, increase or decrease value of A4A7C21. Refer to Table 3-3 for range of values.

29. Move Channel 2 probe to A4A7TPl (left side of C41 SYM).

30. Adjust frequency synthesizer output frequency to peak Channel 1 display.

31. Adjust A4A7C31 PK for maximum peak-to-peak signal on Channel 2 display. See Figure 3-39 for location of adjustment. If unable to achieve a ???peak??? in signal amplitude, increase or decrease value of A4A7C30. Refer to ???Iable 3-3 for range of values.

32.Disconnect Channel 2 probe from A4A7TPl.

33.Adjust frequency synthesizer output frequency to peak Channel 1 display.

34.Adjust [REFERENCE LEVEL_) using step keys to place signal near top CRT graticule line.

35.Adjust A4A7C40 PK for maximum signal amplitude on the CRT

display. See Figure 3-39 for the location of adjustment. If unable to achieve a ???peak??? in signal amplitude, increase or decrease value of A4A7C39. Refer to Table 3-3 for range of values.

36. Disconnect Channel 1 probe from A4A7TP7. Disconnect ???frequency synthesizer output from A4A8Jl and reconnect cable 97 (white/violet).

Adjustments 3-75

7. 3 MHz Bandwidth Filter Adjustments

10 Hz Amplitude Adjustments

37.Connect CAL OUTPUT to RF INPUT. Key in [INSTR PRESET), [mj 9, (jEEki-- 10 Hz.

38.Adjust the instrument front panel FREQ ZERO control for maximum signal amplitude on the CRT display.

40.Key in [REs] 10 Hz.

41.Adjust the instrument front panel FREQ ZERO control for maximum signal amplitude on the CRT display.

42.Adjust A4A7R30 10 Hz AMPTD and A4A7R41 10 Hz AMPTD equal amounts to set the signal level the same as the reference level set in step 39. See Figure 3-38 for location of 10 Hz AMPTD adjusts.

43.Repeat steps 37 through 42 until no further adjustment is required.

3-76 Adjustments

8. 21.4 MHz Bandwidth Filter Adjustments

8. 21.4 MHz

Bandwidth Filter

Adjustments

Reference IF-Display Section

A4A4 Bandwidth Filter

A4A8 Attenuator-Bandwidth Filter

DIGITAL VOLTMETER

rm

1OdB STEP IdH STEP

ATTENUATOR ATTENUATOR

Figure 3-40. 21.4 MHz Bandwidth Filter Adjustments Setup

Adjustments 3-77

8. 21.4 MHz Bandwidth Filter Adjustments

Equipment Digital Voltmeter (DVM) . . . . . . . . . . . . . . . . . . . . . . . .HP 3456A 10 dB Step Attenuator . . . . . . . . . . . . . . HP 355D, Option H89 1 dB Step Attenuator . . . . . . . . . . . . . . . HP 355C, Option H25

Crystal Filter Bypass Network (2 required) . . . . Refer to Figure 3-91

Procedure 1. Position instrument upright as shown in Figure 3-40 and remove top cover.

2.Set LINE switch to ON and press QNSTR PRESET].

+10 V Temperature Compensation Supply Check

3.Connect DVM to A4A5TPl (+ 10 VF).

4.DVM indication should be between +9.0 V dc and + 10.0 V dc. If voltage is within tolerance, proceed to next step. If voltage is not

within tolerance, refer to Adjustment 10, Step Gain and 18.4 MHz Local Oscillator Adjustments, for adjustment procedure.

A4A4 LC Adjustments

5.Set step attenuators to 0 dB.

6.Disconnect cable 97 (white/violet) from A4A8Jl and connect to A4A6J 1.

7.Key in CCENTER FREQ] 20 MHz, (jREs] 100 kHz, [FREQUENCY SPAN) 200 kHz, and press LIN pushbutton.

8.Press (REFERENCE LEVEL) and adjust front-panel knob to set signal peak on screen two divisions from the top graticule.

9.Adjust A4A4C67 LC CTR and A4A4C19 LC CTR for maximum MARKER level as indicated by CRT annotation. See Figure 3-41 for location of adjustments. If unable to adjust LC CTR adjustments for satisfactory signal amplitude, increase or decrease value of A4A4C17 and A4A4C70. Refer to Table 3-3 for range of values.

A4A4

Bnndwdth Filte

\

c

Figure 3-41.

Location of A4A4 21.4 MHz LC Filter Adjustments

3-78 Adjustments

8.21.4 MHz Bandwidth Filter Adjustments

10.Key in CRESBW_) 1 MHz, and ISPAN) 1 MHz.

11.Press MARKER CPEAK SEARCH], MARKER a.

12.Key in CREsBW) 100 kHz, [-SPAN) 200 kHz, and MARKER

[PEAK SEARCH).

13.Adjust A4A4R43 LC to align markers on display. MARKER A level should indicate 1.00 X. See Figure 3-41 for location of adjustment.

14.Repeat steps 10 through 13 until no further adjustment is necessary.

A4A4 XTAL Adjustments

15. Press MARKER loFF). Key in CREsJ 30 kHz and

[FREQUENCY SPAN] 100 kHz.

16.Press [REFERENCE LEVEL) and adjust DATA knob to set signal peak on screen two divisions from the top graticule line.

17.Connect crystal filter bypass networks between A4A4TPl and A4A4TP2 and between A4A4TP4 and A4A4TP5.

18.Adjust A4A4C20 CTR to center signal on center graticule line. Adjust A4A4C9 SYM for best symmetry of signal. See

Figure 3-42 for location of adjustments. If unable to adjust SYM for satisfactory signal symmetry, increase or decrease value of A4A4ClO. Refer to Table 3-3 for range of values.

A4A4

B a n d w i d t h F i l t e r

A4A4

Figure 3-42.

Location of A4A4 21.4 MHz Crystal Filter Adjustments

19.Remove crystal filter bypass network from between A4A4TP4 and A4A4TP5.

20.Adjust A4A4C74 CTR to center signal on center graticule line. Adjust A4A4C39 SYM for best symmetry of signal. See Figure 3-42 for location of adjustments. If unable to adjust A4A4C39 SYM

for satisfactory signal symmetry, increase or decrease value of A4A4C38. Refer to Table 3-3 for range of values.

21.Remove crystal filter bypass network from between A4A4TPl and A4A4TP2.

Adjustments 3.79

8.21.4 MHz Bandwidth Filter Adjustments

22.Adjust A4A4C73 CTR to center signal on center graticule line. Adjust A4A4C65 SYM for best symmetry of signal. See Figure 3-42 for location of adjustments. If unable to adjust A4A4C65 SYM

for satisfactory signal symmetry, increase or decrease value of A4A4C66. Refer to Table 3-3 for range of values.

23.All crystal filter bypass networks are removed. Signal should be centered and symmetrical. If not, go back to step 16 and repeat adjustments.

24.Press MARKER SPEAK SEARCH] and MARKER In].

25.Key in ~FREQUENCY SPAN] 20 kHz, [REs] 3 kHz, and MARKER

[PEAK SEARCH].

26.Adjust A4A4R49 XTAL to align markers on display. MARKER A level should indicate 1.00 X. See Figure 3-42 for location of adjustment.

A4A8 LC Adjustments

27.Disconnect cable 97 (white/violet) from A4A6Jl and reconnect to A4A8Jl. Reconnect cable 89 (gray/white) to A4A6Jl.

28.Key in [-BW) 100 kHz and [FREQUENCY SPAN] 200 kHz.

29.Press [REFERENCE LEVEL) and adjust DATA knob to place signal peak two division from the top graticule line.

30.Adjust A4AW32 LC CTR and A4A8C46 LC CTR for maximum MARKER level as indicated by CRT annotation. See Figure 3-43 for location of adjustments. If unable to adjust A4A8C32 and A4AW46 LC CTR adjustments for satisfactory signal amplitude, increase or decrease value of A4AW35 and A4A8C49. Refer to ???Iable 3-3 for range of values.

A4A8

A t t e n u a t o r BandwIdth F i l t e r

A4A8

Figure 3-43.

Location of A4A8 21.4 MHz LC Filter and Attenuation

Adjustments

31.Key in [REsj 1 MHz and @@?ZGGi] 1 MHz.

32.Press MARKER (PEAK SEARCH] and MARKER @.

3-80 Adjustments

8.21.4 MHz Bandwidth Filter Adjustments

33.Key in t-1 100 kHz, C-1 200 kHz, and MARKER

[PEAK SEARCH].

34.Adjust A4A8R35 LC to align makers on display. MARKER A level should indicate 1.00 X. See Figure 3-43 for location of adjustment.

35.Repeat steps 31 through 34 until no further adjustment is necessary.

A4A8 XTAL Adjustments

36.Key in @TFTiTj 30 kHz, [FREQUENCY SPAN] 100 kHz. Press

MARKER IOFF).

37.Connect crystal filter bypass network between A4A8TPl and A4A8TP2.

38.Press (REFERENCE LEVEL) and adjust DATA knob to place signal peak two division from the top graticule line.

39.Adjust A4ASC44 CTR to center signal on center graticule line. Adjust A4A8C42 SYM for best symmetry of signal. See Figure 3-44 for location of adjustments. If unable to adjust A4A8C42 SYM

for satisfactory signal symmetry, increase or decrease value of A4A8C43. Refer to Table 3-3 for range of values.

A4A8

A t t e n u a t o r - B a n d w i d t h F i l t e r

A4A8

Figure 3-44.

Location of A4A8 21.4 MHz Crystal Filter Adjustments

40.Remove crystal filter bypass network from between A4A8TPl and A4A8TP2.

41.Adjust A4A8C29 CTR to center signal on center graticule line. Adjust A4A8C13 SYM for best symmetry of signal. See Figure 3-44 for location of adjustments. If unable to adjust A4ABC13 SYM

for satisfactory signal symmetry, increase or decrease value of A4A8C14. Refer to Table 3-3 for range of values.

42.Press MARKER CPEAK SEARCH) and MARKER @

43.Key in [FREQUENCY SPAN] 10 kHz.

44.Key in [REsBW) 3 kHz and MARKER CPEAK SEARCH).

Adjustments 3-81

8.21.4 MHz Bandwidth Filter Adjustments

45.Adjust A4ABR40 XTAL to align markers on display. MARKER A level should indicate 1.00 X. See Figure 3-44 for location of adjustment.

LC Dip Adjustments

46.Refer to the Resolution Bandwidth Switching Uncertainty Performance Test, and check all bandwidth amplitudes. If amplitude of 300 kHz bandwidth is low but amplitude of 100 kHz and 1 MHz bandwidths are within tolerance, LC DIP adjustments must be performed. If all bandwidth amplitudes are within tolerance, do not perform the following adjustments.

47 . Set LINE switch to STANDBY.

48.Disconnect cable 97 (white/violet) from A4ABJl and connect to A4A6 J 1.

49.Remove A4A4 Bandwidth Filter and install on extenders.

50.Set LINE switch to ON. Press ~NSTR PRESET).

51.Key in [CENTER FREQUENCY] 20 MHz, [RES] 100 kHz,

~FREQUENCY SPAN] 1 MHz, [ATTEN) 0 dB, and LOG (ENTER dB/DIv] 2

dB.

52.Short A4A4TP3 to ground.

53.Adjust. A4A4C41 LC DIP for minimum amplitude of signal peak. See Figure 3-41 for location of adjustment. Key in CPEAK SEARCH) MARKER Ln], and adjust LC DIP again to offset the signal peak approximately -17 kHz (to the left). This is done to compensate for the effect of placing the board on extenders. If unable to achieve a ???dip??? in signal amplitude, increase or decrease value of A4A4R16. Refer to Table 3-3 for range of values.

54.Remove short, from A4A4TP3 and short A4A4TP8 to ground.

55.Adjust A4A4C43 LC DIP for minimum amplitude of signal peak. See Figure 3-41 for location of adjustment. Key in [PEAK SEARCH) MARKER In], and adjust C43 LC DIP again to offset the signal peak approximately -17 kHz (to the left). If unable to achieve a ???dip??? in signal amplitude, increase or decrease value of A4A4R60. Refer to lhble 3-3 for range of values.

56.Set LINE switch to STANDBY.

57.Reinstall A4A4 Bandwidth Filter without extenders. Short A4A4TP3 and A4A4TP8 to ground. Remove A4A8

Attenuator-Bandwidth Filter and install on extenders. Reconnect cable 97 to A4ABJl and reconnect cable 89 to A4A6Jl.

58.Set, LINE switch to ON. Press QNSTR PRESET).

59.Key in [CENTER FREQUENCY) 20 MHz, CRES] 100 kHz,

(FREQUENCY SPAN) 1 MHz, [ATTEN] 0 dB, and LOG (ENTER dB/DIV] 2 dB.

60.Short A4ABTP6 to ground.

61.Adjust A4ABC66 LC DIP for minimum amplitude of signal peak. See Figure 3-43 for location of adjustment. Key in CPEAK SEARCH) MARKER @, and adjust LC DIP again to offset the signal peak

3-82 Adjustments

8. 21.4 MHz Bandwidth Filter Adjustments

approximately -17 kHz (to the left). If unable to achieve a ???dip??? in signal amplitude, increase or decrease value of A4ABR30. Refer to ???&ble 3-3 for range of values.

62.Remove short from A4ABTP6 and short A4ABTP3 to ground.

63.Adjust A4ABC67 LC DIP for minimum amplitude of signal peak. See Figure 3-43 for location of adjustment. Key in [PEAK SEARCH)

MARKER [nl, and adjust LC DIP again to offset the signal peak approximately -17 kHz (to the left). If unable to achieve a ???dip??? in signal amplitude, increase or decrease value of A4ABR55. Refer to ???Pdble 3-3 for range of values.

64.Set LINE switch to STANDBY.

65.Reinstall A4A8 Attenuator-Bandwidth Filter without extenders. Remove short. from A4ABTP3.

66.Set LINE switch to ON. Press ~NSTR PRESET].

67.Go back and repeat LC adjustments for both the A4A4 Bandwidth filter and the A4A8 Attenuator-Bandwidth Filter.

AlOdB and A20dB Adjustments

68.Set, step attenuators to 25 dB.

69.Key in ~CENTER FREQUENCY] 20 MHz, ~FREQUENCY SPAN_) 3 kHz, CATTEN] 0 dB, [REsBWI) 1 kHz, and [REFERENCE LEVEL) -30 dBm.

70.Key in LOG [ENTER dB/DIv] 1 dB then press MARKER (PEAK SEARCH) MARKER [nl

71.Key in [REFERENCE LEVEL) -20 dBm. Set step attenuators to 15 dB.

72.Adjust A4ABR7 AlOdB to align markers on display. MARKER A level should indicate 0.00 dB. See Figure 3-43 for location of adjustment.

73. Key in (REFERENCE LEVEL) -10 dBm. Set step attenuators to 5 dB.

74.Adjust A4ABR6 A2Od.B to align markers on display. MARKER A level should indicate 0.00 dB. See Figure 3-43 for location of adjustment.

Adjustments 3-83

3-84 Adjustments

9. 3 dB Bandwidth Adjustments

A4A9

IF CONTROL

\

A4A3

Figure 3-45. Location of 3 dB Bandwidth Adjustments

9.Press MARKER a. Adjust marker to 3 dB point on opposite side of signal (CRT MKR A annotation indicates 1.00 X). There are now two markers; one on each side of the signal at the 3 dB points.

10.CRT MKR A annotation now indicates the 3 dB bandwidth of the 3 MHz bandwidth. 3 dB bandwidth should be 3.00 &to.60 MHz.

11.Key in @YWBW) 1 MHz and [FREQUENCY SPAN] 2 MHz. If necessary, readjust [REFERENCELEVEL)~CENTERand FREQUENCY), using DATA knob to place signal peak near top of graticule and centered on center graticule line.

12.Press MARKER [OFF), then MARKER @].

13.Using DATA knob, adjust marker down one side of displayed signal to the 3 dB point; CRT MKR A annotation indicates .707 X.

14.Adjust A4A9R61 1 MHz for MKR A indication of 500 kHz while maintaining marker at 3 dB point (.707 X) using DATA knob. See Figure 3-45 for location of adjustment.

15.Press MARKER a. Adjust marker to 3 dB point on opposite side of signal (CRT MKR A annotation indicates 1.00 X). There are now two markers; one on each side of the signal at the 3 dB point.

16.CRT MKR A annotation now indicates the 3 dB bandwidth of the 1 MHz bandwidth. 3 dB bandwidth should be 1.00 fO.10 MHz.

17.Key in @G?G-BW) 300 kHz and CFREQUENCY SPAN) 500 kHz. If necessary, readjust CREFERENCE LEVEL) and [CENTER FREQUENCY], using DATA knob to place signal peak near top of graticule and centered on center graticule line.

18.Press MARKER (OFF), then MARKER @J.

19.Using DATA knob, adjust marker down one side of the displayed signal to the 3 dB point; CRT MKR A annotation indicates .707 X.

20.Adjust A4A9R62 300 kHz for MKR A indication of 150 kHz while maintaining marker at 3 dB point (.707 X) using DATA knob. See

Figure 3-45 for location of adjustment.

2 1. Press MARKER [nl. Adjust marker to 3 dB point on opposite side of signal (CRT MKR A annotation indicates 1.00 X).

Adjustments 3-85

9.3 dB Bandwidth Adjustments

22.CRT MKR A annotation now indicates the 3 dB bandwidth of the 300 kHz bandwidth. 3 dB bandwidth should be 300.0 f30.0 kHz.

23.Key in @GZVBW) 10 kHz and [FREQUENCY SPAN) 20 kHz. If necessary, readjust PREFERENCE LEVEL] and [CENTER FREQUENCY), using DATA knob to place signal peak near top of graticule and centered on center graticule line.

24.Press MARKER IOFF], then MARKER [ ].

25.Using DATA knob, adjust marker down one side of the displayed signal to the 3 dB point; CRT MKR A annotation indicates .707 X.

26.Adjust A4A9R65 10 kHz for MKR A indication of 5.00 kHz while maintaining marker at 3 dB point (. 707 X) using DATA knob. See Figure 3-45 for location of adjustment.

27.Press MARKER A. Adjust marker to 3 dB point on opposite side of signal (CRT MKR A annotation indicates 1.00 X).

28.CRT MKR A annotation now indicates the 3 dB bandwidth of the 10 kHz bandwidth. 3 dB bandwidth should be 10.0 fl.O kHz.

29.Key in (&YiGBW) 3 kHz and CFREQUENCY SPAN) 5 kHz. If necessary, readjust [REFERENCELEVEL) and [CENTER FREQUENCY], using DATA knob to place signal peak near top of graticule and centered on

center graticule line.

30.Press MARKER (OFF), then MARKER [nl.

31.Using DATA knob, adjust marker down one side of the displayed signal to the 3 dB point; CRT MKR A annotation indicates .707 X.

32.Adjust A4A9R66 3 kHz for MKR A indication of 1.5 kHz while maintaining marker at 3 dB point (.707 X) using DATA knob. See Figure 3-45 for location of adjustments.

33.Press MARKER [nl. Adjust marker to 3 dB point on opposite side of signal (CRT MKR A annotation indicates 1.00 X).

34.CRT MKR A annotation now indicates the 3 dB bandwidth of the 3 kHz bandwidth. 3 dB bandwidth should be 3.00 50.30 kHz.

3-86 Adjustments

PMR METER

DIGITAL VOLTMETER

fi!&

1OdB S T E P 1 dB S T E P

ATTENUATOR ATTENUATOR

Figure 3-46.

Step Gain and 18.4 MHz Local Oscillator Adjustments Setup

Adjustments 3-87

10. Step Gain and 18.4 MHz Local Oscillator Adjustments

Equipment Digital Voltmeter (DVM) . . . . . . . . . . . . . . . . . . . . . . . . HP 3456A Power Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..HP436 A Power Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8481A 10 dB Step Attenuator . . . . . . . . . . . . . . HP 355D, Option H89 1 dB Step Attenuator . . . . . . . . . . . . . . . HP 355C, Option H25

Procedure 1. Position instrument upright as shown in Figure 3-46 and remove top cover.

2.The validity of the results of this adjustment procedure is based in part on the performance of the Log Amplifiers, the Video Processor, and the Track and Hold. These adjustments must be done before proceeding with the adjustment procedure of the Step Gain and 18.4 MHz Local Oscillator.

3.Set instrument LINE switch to ON and press ~NSTR PRESET). Connect CAL OUTPUT to RF INPUT.

4.Key in [CENTER FREQUENCY] 20 MHz, [ R E F E R E N C E L E V E L ] - 1 0 dBm,

(ATTEN) 0 dB, [FREQUENCY SPAN) 0 Hz, [-BW) 1 kHz, l-1 100 Hz, and [SWEEP TIME) 20 ms.

IF Gain Adjustment

5.Disconnect cable 97 (white/violet) from A4A8Jl and connect cable to power meter/power sensor. Refer to Figure 3-47 for location of cable 97 and A4A8Jl.

6.Adjust front-panel AMPTD CAL adjustment for a power meter indication of -5 dBm.

7.Disconnect power meter and reconnect cable 97 to A4A8Jl.

8.Press LIN pushbutton and MARKER (-1.

9.Note MARKER amplitude in mV and adjust A45A5R33 CAL to

70.7mV (top CRT graticule line). See Figure 3-47 for location of adjustment.

R33

C A L

\-w

A4A5

Figure 3-47. Location of IF Gain Adjustment

3-88 Adjustments

10.Step Gain and 18.4 MHz Local Oscillator Adjustments

10.If A4A5R33 CAL adjustment does not have sufficient range to adjust trace to the top CRT graticule line, increase or decrease the value of A4A7R60 as necessary to achieve the proper adjustment range of A4A5 CAL adjustment. See Figure 3-39 for the location of A4A7R60. Refer to Table 3-3 for range of values for A4A7R60.

10 dB Gain Step Adjustment

11.Connect CAL OUTPUT to RF INPUT through 10 dB step attenuator and 1 dB step attenuator.

12.Key in LOG (ENTER dB/DIv] 1 dB and [REFERENCE LEVEL) -30 dBm.

13.Set step attenuators to 25 dB.

14.Key in MARKER A. Signal trace should be at the center CRT graticule line, and MKR A level, as indicated by CRT annotation, should be .OO dB.

15.Key in [REFERENCE LEVEL] -40 dBm. Set step attenuators to 35 dB.

16.Adjust A4A5R32 SGlO for MKR A level of .OO dB (CRT MKR A annotation is now in upper right corner of CRT display). See Figure 3-48 for location of adjustment.

A4A5 S T E P LAIN

A4A5

Figure 3-48. Location of 10 dB Gain Step Adjustments

17.If A4A5R32 SGlO adjustment does not have sufficient range to perform adjustment in step 16, increase or decrease the value of A4A7R60 as necessary to achieve the proper adjustment range of A4A5 SGlO. See Figure 3-39 for the location of A4A7R60. Refer to ???Ihble 3-3 for range of values for A4A7R60. Repeat steps 3 through 16 if the value of A4A7R60 is changed.

18.Key in [REFERENCE LEVEL] -50 dBm. Set step attenuators to 45 dB.

19.Adjust A4A5R44 SG20-1 for MKR A level of .OO dB. See

Figure 3-48 for location of adjustment.

20. Key in CREFERENCE LEVEL) -70 dBm. Set step attenuators to 65 dB.

21.Adjust A4A5R54 SG20-2 for MKR A level of .OO dB. See Figure 3-48 for location of adjustment.

Adjustments 3-89

10. Step Gain and 18.4 MHz Local Oscillator Adjustments

1 dB Gain Step Checks

22.Key in [REFERENCE LEVEL) -19.9 dBm. Set step attenuators to 15 dB. Press MARKER @ twice to establish a new reference.

23.Key in (REFERENCE LEVEL) -17.9 dBm. Set step attenuators to 13 dB.

24.MKR A level, as indicated by CRT annotation, should be .OO f0.5 dB. If not, increase or decrease the value of A4A5R86. Refer to ???Ihble 3-3 for range of values.

25.Key in (REFERENCE LEVEL) -15.9 dBm. Set step attenuators to 11 dB.

26.MKR A level should be .OO ho.5 dB. If not, increase or decrease the value of A4A5R70. Refer to Table 3-3 for range of values.

27.Key in [REFERENCE LEVEL) -11.9 dBm. Set step attenuators to 7 dB.

28.MKR A level should be .OO ho.5 dB. If not, increase or decrease the value of A4A5R62. Refer to ???Ihble 3-3 for range of values.

.l dB Gain Step Adjustment

29. Key in LIN, (SHIFT) * (AUTO] (resolution bandwidth), and

(REFERENCE LEVEL) -19.9 dBm. Set step attenuators to 13 dB. Press MARKER (nl twice to establish a new reference.

30.Key in [REFERENCE LEVEL) -18.0 dBm. Set step attenuators to 11 dB.