User Guide

NHB–3
Technical Documentation
PAMS
Service Accessories
Original 26/97
Page 12
Service Box JBS–7
Product code: 0770015
Service box provides convenient test environment (regulated power supply,
M2BUS, preset battery reference voltage, external RF connection, audio test
loops, HOOK switch etc) and mechanical interface in one box.
When AUDIO switch of JBS–7 is INT position, the AF signals are routed nor-
mally to the modular–type system connectors. When in EXT position, the AF
signals are routed from the speaker pin of the bottom connector straight back to
the external microphone pin of the phone. Thus the speech codec of the phone
is able to feed the internally generated test signal to the loudspeaker line, and
measure the same signal from the EXT MIC line. Whenever audio signals are
to be monitored or measured outside the phone, the AUDIO switch of the
JBS–7 must be in INT position.
HOOK switch of the JBS–7 enables the audio signals to be routed to and from
the phone via the bottom connector also when the phone is in cellular mode, for
example during a test call to some cellular tester. When HOOK switch is in
OFF position and the phone in cellular mode, the audios are always routed to
ear–piece and internal microphone.
Additionally JBS–7 has a spare battery slot, through which the battery may be
connected to external capacity meter.