ADJUSTMENT OF SIDETONE OR R/C BALANCE
The R/C is a onetime only adjustment. Only in those situations where the TELCO module is
connected to another telephone line a repeated adjustment could be necessary.
NOTE: The R/C balance trimming can only be performed after you have correctly followed the N-1
alignment procedure.
1. Power down the AIRLAB.
2. Connect the TELCO module to the right connectors and horizontally lay down the module on
the surface of the other modules. Put an isolating material between the TELCO module and
the surface of the other modules to avoid damage and shorts.
3. Connect an audio source to one of the modules and activate the
SUB switch only!!
4. Connect the telephone system to the TELCO module’s WALL connector.
5. Connect a Phone appliance to the “TO PHONE” connector.
6. Check if there is no short between PCB of the TELCO module and the surface it is put on.
7. Power up the AIRLAB.
8. Now dial on the connected Phone appliance a number outside the building.