BSX Isolated Audio Entry System
PD-142 Issue 1
Installation and Operating Manual
Page 19 of 32
Adjusting the 61 Speech Unit
The Model 61 Speech Unit has 2 volume controls:-
A (Speaker symbol): controls the speech level from phone to panel.
B (Microphone symbol): controls the speech level from panel to phone.
Initially set both controls to mid-position and adjust each in turn for optimum speech clarity.
It should be noted that if either or both controls are turned too high there will be a howling
sound caused by acoustic feedback. This problem may also be induced by allowing a
space between the speech unit and the inside surface of the panel (i.e. grill).
Battery Tests
Now connect the battery.
Then test the system again with any phone, firstly with the mains on and secondly with it
off. If the system fails to operate satisfactorily when the mains is switched off, then check
the battery fuse inside the Cab3/5 and also the battery voltage (should be >10.4V, 13.8V
+/-0.25V fully charged). If the battery voltage is low then allow it to charge for at least 30
minute and test again.
Cab3 or Cab5 power supplies can shut down their output for 15 minutes if the battery is
very discharged.
For further power supply diagnostic information see the Troubleshooting section Page 20.