Unit installation

1-4

the PL decoder board to filter the PL signal out of the receiver's audio before it goes to the RLC-3.

Connecting the Receiver Audio

- 2 types of audio can be used on the RLC-3 controller:

Type 1: De-emphasized audio (Speaker Audio)

Type 2: Discriminator audio (Raw Unsquelched Audio)

- If type 1 audio is used, set configuration switch #1 (labeled "DM") to the "OFF" position

This removes the de-emphasis filter from the circuit. If you are using discriminator audio, turn

switch #1 on. The filter will not allow PL to pass through the controller. Contact Link

Communications Inc. if you need to pass PL through the controller.

- The audio input is connected to pin #5 of the male DB-9 connector

- The audio adjustments will be described in Step #5.

- Prefered audio input level to the controller is 100mV - 500mV peak-peak audio

Summary of Switch Settings

• Switch #1 (labeled "DM"): If this switch is on, the de-emphasis filter will be connected to

the input audio circuit. You would use this setting for discriminator audio. If this switch is

off, the audio is "flat" through the controller. You would use this setting for speaker audio.

• Switch #2 (labeled "CR"): If this switch is on, the COR signal will be treated as an active

low signal (ground when a signal is present, above 5 volts when absent). If it is off, the

COR signal will be treated as active high.

• Switch #3 (labeled "PL"): If this switch is on, the PL signal will be treated as an active low

signal (ground when a signal is present, above 5 volts when absent). If it is off, the PL

signal will be treated as active high.

• Switches #4 and #5 (labeled "A1" and "A2"): These switches are not currently used.