Door Phone Tuning

[garym999]

Comfort II,

What is the recommend procedure for tuning a door phone and what exactly do the different volume settings do in comfigurator? I\'ve read the manuals but no luck.

The reason for asking is that I can get the doorphone and housephone to work well also the same for the keypad but when I dial in via my mobile I get a real lack of volume  Turning the Phone Intercom Volume\" up in comfigurator past the half way mark puts me very close to creating local feedback within the doorstation. Are there any tuning values that can be tweaked because pots and sliders are not doing it for me?

[slychiu]

The Tuning parameters in Modules and settings are not adustable except for the ones that are available in Voice Settings

The Phone Intercom Volume is the gain from Phone to Intercom

If the volume from Door station/KP to phone is low, you can adjust the MIC trimmer near the KP or DP MIC/VOICE terminal blocks

Part of the reason for low volume is that the system tries to compensate for echo, ie if it sees that the Loop gain is hgh, it will reduce the volume of one of the paths to eliminate howling. The system is constrained by the accoustic echo from Speaker to Mic in the KP/DP. This echo should be minimised to avoid howling and to improve volume. The sponges/Rubber parts in the KP/DP housing are very important in reducing the accoustic echo. I wonder if you are using one of the bespoke metal door stations, in which case there may not be the required rubber parts within to reduce echo. If that is the case you need to place hard sponge or rubber to try to reduce the path from speaker to mic

I hope this helps
We will try to produce a better guide and method for tuning te parameters

regards

[garym999]

Cool, yep is one of those MDP. It was the first one I did my testing b4 I introduced it to Andrew and hence it is effectivley wired in place of the Mic and Speaker of a door phone and not the DM01. It worked fine with Comfort I but has not worked that well with Comfort II.

However one of my clinets has a MDP, DM01 and Comfort II and has not complained so may be that has some thing to do with it.

Your descriptions have helped with diagnostics. Checking out the isolation inside the MDP...

• It is made of a hard cast alloy case
  
• The mic has a small foam windshield
  
• The mic is mounted in a rubber sleeve
  
• The back of the mic is sealed with wax
  
• The speaker is mounted direct to the alloy case

I have played around with this a little but it has not made a signifficant difference. Obvoisly the speaker and mic are rather close. Maybe the DM01 is buffering the signals in some way. I\'ll try one of these when I get a chance.

[slychiu]

See news on the new Tuning Guide in http://www.comfortforums.com/forum16/323.html