Switches; Voice Level - Linkcom Door phone User Manual

2.1.4 Switches

7. The switch number 1 (see figure – 8) activates heating of the
PCB. This is for increased resistance against humidity. To use this
feature you must connect an external 12V power supply.
8. The switch number 2 (see figure – 9) is required for programming
the unit when the password is forgotten. It is performed by ordinary
phone (DTMF – tone dial ).
The switch is
The PCB heating has two major benefits. Firstly, it warms the
board during winter time (temperatures under -20 C, most circuits have warranty operation down to -20
C) and secondly it helps to protect the PCB against humidity when installed outside.

2.1.5 Voice level

9. Voice communication – the trimmer position is factory and should be suitable for most
installations. Change the trimmer position only when necessary.
The trimmer "MIC" is designed for microphone volume
setting. The trimmer "SPK" is designed for loudspeaker
volume setting.
The volume settings are more than adequate for most
situations. Therefore we do not recommend setting the
trimmer position more than ½. The most suitable position is
1/3 from minimum amplification.
The trimmer "TRH" is designed for setting the microphone
activation level. It allows balancing between the microphone
and speaker to eliminate feedback. This setting is also
influenced by the noise of the surrounding environment.
Set up Process: The trimmers MIC and SPK are set to ¼
position from minimum loudness level (turn fully anti-clockwise
for minimum). The trimmer TRH is set to a central position. To
fine tune, make a test call. Speak quietly, and by adjusting the
trimmer TRH from the central position anticlockwise, your speech should be heard more clearly by the
PBX user. The amplification of the speaker can be adjusted according to your requirements. Voice
interruption might occur if you set the amplification too high. In this case you can use the trimmer TRH to
correct the balance between the speaker and the microphone.
5