25
OPTIONAL
OPTIONAL
OPTIONAL
OPTIONAL
OPTIONAL
CONFIGURA
CONFIGURA
CONFIGURA
CONFIGURA
CONFIGURATIONS
TIONS
TIONS
TIONS
TIONS
CAUTION: THE FOLLOWING SECTIONS ARE FOR USE BY QUALIFIED SERVICE
PERSONNEL ONLY. TO REDUCE THE RISK OF ELECTRIC SHOCK DO NOT
PERFORM ANY SERVICING, OTHER THAT THAT CONTAINED IN PREVIOUS
SECTIONS, UNLESS YOU ARE QUALIFIED TO DO SO.
WARNING: BE CERTAIN THAT THE POWER CORD IS DISCONNECTED FROM
THE ELECTRICAL MAINS BEFORE ATTEMPTING ANY OF THE FOLLOWING
RECONFIGURATIONS.
MICROPHONE GAIN ADJUSTMENT
As supplied, the microphone preamplifier card, Part No.
1620-MC
, is set for 64 dB of gain, which should be adequate for most
installations. If necessary, the gain may be changed with the trim potentiometer on the top edge of the card. The range of adjustment
is 20 dB. Set to minimum (CCW position), the gain is 60 dB; set to maximum (CW position), the gain is 84 dB. The potentiometer may
be accessed by removing the three screws that secure the top of the 1620LE, then removing the top cover. There is one screw at the
centre front of the top panel, and two others on the rear lug of the top panel. Be sure to replace all three screws when reinstalling the
cover.
