FLEXCOMM
II
C-5000 (Non-Digital)
Installation Manual
150-1355-000 Rev. M
CONFIDENTIAL AND PROPRIETARY TO COBHAM
Page 83
Pin - Signal Name (Continued)
N - DATA SHIELD GROUND
Spare ground.
P - MAIN SQUELCH ANNUNCIATE
This output sinks 30 mA to ground when the main receiver signal-to-noise
squelch conditions are met.
R - GUARD SQUELCH ANNUNCIATE
This output sinks 30 mA to ground when the guard receiver signal-to-noise
squelch conditions are met.
S - AM/FM MODE INDICATOR
This output sinks 30mA to ground when the RT-5000 is in AM mode.
T - VHF/UHF MODE INDICATOR
This output sinks 30mA to ground when the RT-5000 is tuned to a frequency
that is less than 400 MHz.
U - VHF_LO MODE INDICATOR
This output sinks 30mA to ground when the active frequency is less than 88
MHz.
V - ATTENUATOR CONTROL
When this input is pulled to ground, the RT-5000 will engage a 10 dB receive
attenuator in both main and crystal synthesized guard receivers.
W - ON/OFF
When this input is pulled to ground by the C-5000, power is applied to the RT-
5000.
X - GUARD SQUELCH DISABLE
When this input is pulled to ground, the guard squelch conditions are overridden.
Y - MIC HI IN
This input is the standard 150 Ohm carbon microphone high input. The nominal
input is .25 Vrms and is adjustable over a range of .125 Vrms to 1.5 Vrms. The 3
dB bandwidth is 100 Hz to 8.7 kHz for raw audio and 300 Hz to 3 kHz for
processed audio per EIA specifications.
Z - MIC LO/PTT IN
This input when pulled to ground, places the radio in transmit mode if the
transmit bit is set in the serial data stream. This input also forms the low side of
the standard 150 Ohm carbon microphone.
a - EXTERNAL PTT
If the radio is controlled by a controller other than a C-5000, the RT-5000 will
transmit if this pin is grounded.