reference for all inputs.
Pinout Description
Pin Number
Description
1
CS0-Least significant bit of the channel select lines. Active high 5 volt TTL/CMOS
level. Internal 10 k pull-up to +5 volts.
2
CS1-Mid bit of the channel select lines. Active high 5 volt TTL/CMOS level. Internal
10 k pull-up to +5 volts.
3
CS2-Most significant bit of the channel select lines. Active high 5 volt TTL/CMOS
level. Internal 10 k pull-up to +5 volts.
Channel
CS2
CS1
CS0
1
0
0
0
2
0
0
1
3
0
1
0
4
0
1
1
5
1
0
0
6
1
0
1
7
1
1
0
8
1
1
1
0 = Logic low
1 = Logic high
Note: Due to the internal pull-up resistors, the unit defaults to channel 8 if the channel
pins are left open (unconnected).
Channel 8 would be the nominal channel when the
Ritron programmer is connected.
4
MIC IN-Microphone input. This input accepts microphone-type input signals for
transmit. This input is a higher gain version of the AUX IN input. This input is not
available in very narrow channel mode.
5
CSN-Depending upon how it is programmed, this input selects between channels 1 and 2
or between high and low RF output power. This input is TTL/CMOS level type input
with a logic low required for channel 1/low power and a logic high required for channel
2/high power. Internal 10 k pull-up to +5 volts.
6
RAW SUPPLY- The positive supply voltage for the unit is supplied through this pin.
The actual supply voltage required depends upon model type. Ensure that the correct
supply voltage per the given model is used.
7
AUX IN-This is the main audio input for modulation. The gain through this input to the
modulator is programmable, as is the use of pre-emphasis, but not independently of the
MIC IN. This signal passes through the clipper and clipper filter.
8
AUX OUT-This is the broadband output of the receiver. The gain from the receiver to
the output is programmable, as is the use of de-emphasis. The choice of AC or DC
coupling from the RF board discriminator is also programmable. The coupling at the
output of this pin is AC coupled, however. It can be converted to DC coupling with
internal hardware modifications.
Note: The output impedance is approximately 600
