D&R Airlab User Manual page 47

Installing/Servicing the Airlab
9. Move the TELCO modules fader to its 0 dB position. Press the ON switch and activate the
PROG and SUB switch only. The LINE IN switch should be off (up).
10. CHECK if the CRM outputs this PHONE IN signal coming from the PROG buss, (No CRM
select switches are active) to be sure that you have correctly connected and routed your
source.
11. Now open the fader on the channel where you have connected your audio and Press the ON
switch on that channel.
12. Now you shall hear the audio signal through the TELCO module that is fed from that channel.
13. Now adjust the front panel trimmer VR1 (labeled R-BAL) to a minimum audio position and look
for the best combination of C jumper settings and trimmer position.
14. Power down the console and install the module again properly.
As long as the hybrid remains connected to the same "Phone Company", no changes need to be made to
this setup. If more TELCO modules need to be aligned the same capacitor value shall be used for all
modules so front panel trimming is the only trimming that is left to do for the other modules.
Try to by-pass the in house telephone system if possible. Otherwise it will be extremely difficult to achieve
a good alignment. A direct connection with the incoming phone company gives best results.
When installing new (extra) modules in your Airlab it's necessary to re-adjust the internal power supply
voltages to guarantee a stable performance at all times.
More current is taken from the internal power supply because you have put in more modules now. It's
necessary to adjust the power supply voltage to a precise level of 18 volts for both the positive and
negative rails with all modules connected.
Adjustment is performed on the power supply PCB mounted on the bottom of the console located beneath
the master section.
Power supply voltage is measured across the output terminals of the power supply PCB inside the console.
NOTE: If the power supply voltage is not adjusted to 18 volts again, it may be possible that
certain logic functions may not work properly at all times.
Airlab from D&R Phone +31 294 418014, email:
NOTE: INSTALLATION OF NEW (EXTRA) MODULES
info@d-r.nl Page 47