BSX Isolated Audio Entry System
PD-142 Issue 1
Installation and Operating Manual
Page 23 of 32
Call the phone under test by pressing the required button and confirm by observing that
the corresponding LED on the BSX PCB is illuminated
Using a voltmeter:
a) Check the voltage between I and O: +12V pulsing (The ring voltage)
b) Check the voltage between V and O: +12V steady (Power for BS-LX model only)
Repeat the voltage test at various points as detailed below to diagnose the fault:-
Test
Result
Action
Test voltages at phone PCB
OK
Check phone by substitution
Otherwise:
Test voltages at BSX PCB
OK
Faulty cable or connections
If Not OK
Check fuse
Otherwise:
Unplug phone connections;
Test voltages at BSX PCB
OK
Faulty cable or connections
If Not OK
Check fuse
Call Technical