I have an british army vehicle which has a Clansman intercom system in, a clansman radio can be connected in to the intercom system but I want to connect a GM300 to the intercom system, I have the lead that connects the clansman radio but I don't know what pins on the rear of the GM300 to connect to.
my clansman plug has a 6 wire pinout,
A = Mic +
B = Mic -
C = a live supply from the clansman radio
D = Left Headphone
E = Headphone & PTT Ground
F = PTT (when < 1600 ohms to Ground)
Can anyone recommend what pin to connect what to
Thank You
Lance
connecting a gm300 in to a clansman intercom systerm
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Re: connecting a gm300 in to a clansman intercom systerm
http://www.batlabs.com/images/gmacc16.giflancerice wrote:I have an british army vehicle which has a Clansman intercom system in, a clansman radio can be connected in to the intercom system but I want to connect a GM300 to the intercom system, I have the lead that connects the clansman radio but I don't know what pins on the rear of the GM300 to connect to.
my clansman plug has a 6 wire pinout,
A = Mic +
B = Mic -
C = a live supply from the clansman radio
D = Left Headphone
E = Headphone & PTT Ground
F = PTT (when < 1600 ohms to Ground)
Can anyone recommend what pin to connect what to
Thank You
Lance
Suspect you'll need a matching transformer so as not to blow up the audio circuit in the radio
Good luck
-
Astro Spectra
- Posts: 669
- Joined: Sat Sep 22, 2001 4:00 pm
Re: connecting a gm300 in to a clansman intercom systerm
Try:
http://www.vmarsmanuals.co.uk/newslette ... erface.pdf
The reasons for the complexity are as follows:
Most military radios systems (like aviation radios) use high impedance headphones and allow multiple cans to be in parallel. So the radio can see from 600 ohms (one side of one headset) down to 75 ohms (4 headsets both sides). To drive the harness properly you’re going to need at least 1.5V RMS into 75 ohm.
In the Clansman the microphones are either 300 ohm dynamic (black PTT) or electret (in the green PTT automatic noise reduction versions) both have similar outputs in the range 80 mV to 4V RMS. PTT opertion is indicated over the harness by a DC resistance between the Mic in + and Mic in - pins (see below) the resistance needs to be such that about 10mA flows for the transmit condition.
The pinout you've shown is for the Audio sockets of the Clansman radio, the Harness connector (which you use to connect to the intercom system) has a different pinout as follows:
A Mic in +
B Mic in -
C Earth
D Phone out +
E Phone out -
F not used
G Earth
http://www.vmarsmanuals.co.uk/newslette ... erface.pdf
The reasons for the complexity are as follows:
Most military radios systems (like aviation radios) use high impedance headphones and allow multiple cans to be in parallel. So the radio can see from 600 ohms (one side of one headset) down to 75 ohms (4 headsets both sides). To drive the harness properly you’re going to need at least 1.5V RMS into 75 ohm.
In the Clansman the microphones are either 300 ohm dynamic (black PTT) or electret (in the green PTT automatic noise reduction versions) both have similar outputs in the range 80 mV to 4V RMS. PTT opertion is indicated over the harness by a DC resistance between the Mic in + and Mic in - pins (see below) the resistance needs to be such that about 10mA flows for the transmit condition.
The pinout you've shown is for the Audio sockets of the Clansman radio, the Harness connector (which you use to connect to the intercom system) has a different pinout as follows:
A Mic in +
B Mic in -
C Earth
D Phone out +
E Phone out -
F not used
G Earth