Unit installation

1-5

Step #4: Connecting Your Transmitters to the RLC-3

Transmitter PTT

- The RLC-3 produces an active low PTT signal (ground when PTT is active). This output is

buffered with an open collector type driver capable of sinking 150mA. There is a built in 30V zener

clamping diode to protect the PTT MOSFET from the high voltage spikes that can be caused by

interfacing to a PTT relay coil. Your transmitter PTT input should be connected to pin #3 of the

DB-9 connector.

Transmitter Audio

- The RLC-3 provides a 600 output impedance to your transmitter audio input.

- The transmitter audio is connected to pin #4 of the DB-9 connector.

- If it is not already, the DB-9 plug can now be plugged into the appropriate jack on the link card.

The radio port is the lower DB-9 on the link card (with the DB-9s toward you).

- You may need to adjust the mike level pot on your transmitter to give the controller more range

in its adjustments. A good rule is to set the transmit pot on the controller mid scale in its

adjustment. Then set your transmitters mike level pot to obtain the correct deviation.

Step #5: Adjusting the RLC-3 Controller

- Locate connector P4 on the RLC-3's main board. (It is the 10 pin female connector located near

the power connector and above the serial port connector). There is one pin for each receiver's

audio (labeled 1..8 to correspond with the number of the card the receiver is connected to), one for

DVR audio (labeled D) and one for the voice synthesizer (labeled V). This test bus will provide the

signals that we need to adjust the audio inputs on the RLC-3. In order to maintain audio deviation

during channel switching, all of the receiver inputs must be set to the same level. These signals can

be measured with an oscilloscope or an AC voltmeter. If you are using an AC voltmeter, remember

that it reads AC signals as RMS values. In order to obtain an audio signal on P4, a valid COR or

PL must be received. Once a valid access signal is received, the RLC-3 will un-squelch the audio

and be present on P4.

Receiver Port Adjustment:

- Connect the receiver port that is receiving a signal to all connected transmitter ports.

Command 000 <rx port> <transmit port1>...Command 000 <rx port> <transmit port8>

Transmitter Port Adjustment:

- Present a stable Tone or DTMF tone to the receiver that you are adjusting.

- Adjust the 'RX' pot so that the signal on P4 is 1 volt peak-to-peak for the active receiver

- Adjust the 'TX' pots on all other connected transmitters to obtain the desired deviation.

- Your transmitters should not need any additional adjustments once one receiver is set up.

Follow the above adjustment steps for all other connected receivers

Voice Level Adjustment:

- Generate a voice test message using RLC-3 command 036

Example: 036 001 002 003 004 005 006 007 D or unkey or <Enter>

- Adjust 'Voice Level Adjust' pot to 2 Khz deviation, this adjustment is for all transmitters.