MONITOR MODE
Monitor
The high impedance monitor allows observation of the line for service quality or availability. There will be no perceptible click or reduction of level to callers when it is connected. Monitor is safe on digital and data circuits but be careful with digital signals - they may not be au- dible.
Sounder
The sounder will warble in Monitor mode when there is an incoming call and it will chirp if connected across a line with live Pulse dialling. It will also buzz continuously if an attempt is made to go off hook on a high voltage digital service,
see the section on DSP.
Polarity test
The polarity test may be conducted on a line after monitoring to en- sure the line is free. Do not test polarity during live calls - it will cause loud clicks. Connect to line, press the polarity button and observe the polarity window at the centre of the keypad.
If you are using an accessory
Red LED = Red wire connected to positive.* Green LED = Red wire connected to negative.
*UK plug: pin 2 positive, pin 5 negative.
*RJ11 plug: pin 4 positive, pin 3 negative.
WARNING:
Do not conduct the polarity test in the presence of AC power. Dam- age to the unit will result.
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