LECTROSONICS, INC.10
Connecting the Signal Source
Microphones, line level audio sources and instruments can be used with
the transmitter. Refer to the section entitled Input Jack Wiring for Different
Sources for details on the correct wiring for line level sources and micro-
phones to take full advantage of the Servo Bias circuitry.
Adjusting the Input Gain
The two bicolor Modulation LEDs on the top panel provide a visual indication
of the audio signal level entering the transmitter. The LEDs will glow either red
or green to indicate modulation levels as shown in the following table.
Signal Level -20 LED -10 LED
Less than -20 dB Off Off
-20 dB to -10 dB Green Off
-10 dB to +0 dB Green Green
+0 dB to +10 dB Red Green
Greater than +10 dB Red Red
NOTE: Full modulation is achieved at 0 dB, when the “-20” LED first
turns red. The limiter can cleanly handle peaks up to 30 dB above this
point.
It is best to go through the following procedure with the transmitter in the
standby mode so that no audio will enter the sound system or recorder during
adjustment.
1) With fresh batteries in the transmitter, power the unit on in the standby
mode (see previous section Powering On in Standby Mode).
2) Navigate to the Gain setup screen.
Gain
Freq.
ProgSw
Rolloff -40 -20 0
Gain
25
3) Prepare the signal source. Position a microphone the way it will be used
in actual operation and have the user speak or sing at the loudest level
that occur during use, or set the output level of the instrument or audio
device to the maximum level that will be used.
4) Use the and arrow buttons to adjust the gain until the –10 dB glows
green and the –20 dB LED starts to flicker red during the loudest peaks
in the audio.
5) Once the audio gain has been set, the signal can be sent through the
sound system for overall level adjustments, monitor settings, etc.
6) If the audio output level of the receiver is too high or low, use only the
controls on the receiver to make adjustments. Always leave the trans-
mitter gain adjustment set according to these instructions, and do not
change it to adjust the audio output level of the receiver.
