Switches, Voice level | Link electronic Door phone manual

2.1.4Switches

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.

2.1.5Voice 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.