Listen Technologies LA-123, Design Manual

Page: 32 / 65

26
LT-800
LT-803-072
LT-803-072 Operating Instructions
Test Tone (if necessary)
Adjust Audio Input Level
Turn the input knob counter-clockwise to add gain to Input 1. This will decrease gain to Input 2.
Turn input knob clockwise to add gain to Input 2. This will decrease gain to Input 1. If you have two
audio sources connected to Input 1 and 2, adjust the level of one input using the VU meter, then
adjust the output level of the other audio source. Adjust the input level until the left VU meter(s)
occasionally illuminate the red LEDs. Illumination of the red LEDs indicates the unit is in limiting.
Limiting is required so that the unit does not over-modulate the transmit signal. If you don’t want
any audio limiting to occur, make sure the red LEDs never illuminate. If you want a highly limited
signal, turn the audio gain up so the red LEDs illuminate often.
4
1
Adjusting Audio Levels
LT-803 LT-803
Test Tone Button
LT-803 LT-803
Audio Input Level Knob
Use the test tone to transmit a 400 Hz tone. This tone will allow the receiver to know if the system is
transmitting properly. All receivers should be able to hear this tone if tuned to the proper channel.