General Description

The RI 150 is an extremely lightweight wideband stethoset receiver which uses the carrier frequency 2.3 MHz, thus offering excellent transmission reliability. It features an easy-to-operate on/off/volume control and is powered by the environmentally friendly BA 151 rechargeable NiMH accupack delivered with the receiver. The audio- logy variant RI 250 is fitted with an additional, recessed balance control. The RI 250 J is fitted with a 3.5 mm jack output socket.

Features

???Wideband stethoset receiver

???Extremely reliable transmission due to carrier frequency 2.3 MHz

???Extremely lightweight ??? only 45 g

???Excellent speech intelligibility and good music reproduction

???Very easy to use

???Operates on environmentally friendly rechargeable NiMH accupack

???Delivery includes:

RI 150: 1 x RI 150 mono stethoset receiver, 1 x BA 151 accupack

RI 250 and RI 250 J: 1 x RI 250 or RI 250 J mono stethoset receiver,

1 x BA 151 accupack, 1 set of adhesive tape for altering the frequency response

188 mm

137 mm

Dimensions of the RI 150/RI 250/RI 250 J

Two IR receiving diodes (behind special plastic cover)

On/off/volume control

Apertures for altering the frequency response

Audio output, 3.5 mm jack (RI 250 J only)

Inserted BA 151 accupack

The RI 150 mono receiver works on the extremely reliable carrier frequency 2.3 MHz, offering excellent speech intelligibility and good music reproduction due to its wide frequency response. A built-in squelch avoids loud hiss when the signal from the IR radiators is too weak, for example when a receiver is used outside the radiator cover- age area. The RI 150 is an elegantly shaped receiver which is very easy to use: the only control the wearer has to operate in order to hear the transmitted signals is a combined on/off/volume control with a small position indicator for reading off the volume.

The audiology variant RI 250 has additionally been fitted with a balance control to compensate for hearing differences between the ears. The audiology version has a higher SPL and comes with strips of adhesive tape for covering the apertures on the earpieces. By sealing them, low-frequency response can be altered: the more apertures are covered, the more the lower frequencies are attenuated. Thus, speech intelligibility is increased without increasing the volume. Due to its balance control and the option of altering low-frequency response, the RI 250 can be ideally matched to the ears of its user.

At the bottom, the variant RI 250 J is fitted with an audio ouput socket (3.5 mm jack). Users can wear the stethoset receiver as usual, or they can put the stethoset arms around their neck and connect a pair of headphones to the receiver output

RI 150/RI 250/RI 250 J stethoset receiver

Excellent ease of operation: The user has only to operate the on/off/volume control

socket or have the sound transmitted to a suitable hearing aid via induction cou- plers or an induction neck loop. The RI 250 J also comes with strips of adhesive tape for altering the frequency response.

The receivers are powered by the environmentally friendly BA 151 NiMH accupack. For domestic applications, the L 151-2 charger is the optimum choice: it is designed for two BA 151 accupacks and comes complete with mains unit. For professional applications, Sennheiser has designed the L 151-10 charging unit. It can recharge up to ten BA 151 directly in the receivers, as the accupack charging contacts are located on the outside. Alternatively, you can also charge BA 151s separately, e.g. in case you have spare accupacks. The L 151-10 requires the NT 92 plug-in mains unit, which can be ordered separately in the version you require (European, UK or USA versions available).

The L 151-10 can also be cascaded: up to five charging units can be joined by means of the cascading bars fixed to the bottom of the units. Two to five cascaded L 151-10 are powered by an NT 2013 (or NG 2013-UK) plug-in mains unit. The recharging of the receivers is carried out automatically and takes 10 hours. After that, the charg- ing unit switches to trickle charging.