25H/SP/DDA/2W - TECHNICAL MANUAL
EN-UK - V.1.2 - 04/01/16
9
VIDEX
25H/SP/DDA/2W
(1 way “2 wire” DDA audio intercom kit)
BALANCE
BALANCE
BALANCE
Switches 6, 7 and 8 are used to setup the device
number of the Art.138N
(these switches are usually
only set when there is a VX2210 concierge unit on
the system where the intercom panel making the
call needs to be identified on the concierge. It is
also used on video systems when camera recall is
required for each door).
Volume Adjustments
There are three adjustable POTs available on the Art.138N amplifier module for speech volume adjustment.
This system uses only one wire to carry both directions of speech and so it is necessary to use the balance
POT to adjust the gain of the two speech directions to the required levels*.
microphone volume
adjustment
speaker volume
adjustment
balance control for
microphone and speaker
switch 6 OFF
switch 7 OFF
switch 8 OFF
= device 1
switch 6 ON
switch 7 OFF
switch 8 OFF
= device 2
switch 6 OFF
switch 7 ON
switch 8 OFF
= device 3
switch 6 ON
switch 7 ON
switch 8 OFF
= device 4
switch 6 OFF
switch 7 OFF
switch 8 ON
= device 5
switch 6 ON
switch 7 OFF
switch 8 ON
= device 6
switch 6 OFF
switch 7 ON
switch 8 ON
= device 7
switch 6 ON
switch 7 ON
switch 8 ON
= device 8
(
*Volume adjustment tip:
set the speaker and mic POTs to approximately a third of a turn and then during ‘live’
speech adjust the balance POT whilst rubbing the bottom of the mic cap. Continue adjusting the balance POT to
the point at which the minimum volume of speech comes through the door panel’s speaker. Finally adjust the
speaker and mic POTs to optimal level ensuring that no feedback occurs when the panel is placed back into the
back box).
