That is a 10 watt AM transmitter. The TX RX ports on the back allow you to use one antenna for transmit and receive. The antenna connecting to the antenna port, and the receiver to the rx port. The J5 connector is where you connect the "key" pair, and the audio pair to modulate the carrier. The voice comes from a remote console in the control tower. Ultimately to an Enhanced Terminal Voice Switch. If you open the tuning ports, you should see some "pots" that adjust an internal band-pass filter. Every time the frequency is changed you must tune these ports to get max. RF out. The alc connector will put out a DC voltage that is used to fine tune the unit. Before tuning, set the power on the front panel to 2 or it will show an error code. The power numbers don't mean anything. If I recall 65 is really like 10 watts carrier power.
That is just a UHF transmitter, old version of the CM300s. You are missing the blue receiver unit. You are some what right about the xmit pwr(this is not direct conversation to watts), it does help in tuning the radios pwr output.
If it isn't a transceiver and is TX only, I wonder if it has an internal T/R switch and the RX port would function as a pass thru to a separate receiver?
The lack of a speaker, audio port and that J5 socket makes me think it is designed to be operated remotely. So this sits at the bottom of a radio mast but is operated from the tower some distance away. Curious if the Mic jack is TX only or more likely David Clark-style TX/RX for an avionics headset as this will be deployed in a very high noise environment.
That is a 10 watt AM transmitter. The TX RX ports on the back allow you to use one antenna for transmit and receive. The antenna connecting to the antenna port, and the receiver to the rx port. The J5 connector is where you connect the "key" pair, and the audio pair to modulate the carrier. The voice comes from a remote console in the control tower. Ultimately to an Enhanced Terminal Voice Switch.
If you open the tuning ports, you should see some "pots" that adjust an internal band-pass filter. Every time the frequency is changed you must tune these ports to get max. RF out. The alc connector will put out a DC voltage that is used to fine tune the unit. Before tuning, set the power on the front panel to 2 or it will show an error code. The power numbers don't mean anything. If I recall 65 is really like 10 watts carrier power.
Cool, do you have any docs on these units?
That is very good brief explanation of the radio.
Wow this looks really cool!!
That is just a UHF transmitter, old version of the CM300s. You are missing the blue receiver unit. You are some what right about the xmit pwr(this is not direct conversation to watts), it does help in tuning the radios pwr output.
What a deal! I bet you can pick up traffic from your local USAF base with great clarity
I can respond with signal reports too!
@@W9CR They'd LOVE that, and you'd quickly make new friends!
if its 220 AM means it was for the military but if i remember right they use 380 not 220
If it isn't a transceiver and is TX only, I wonder if it has an internal T/R switch and the RX port would function as a pass thru to a separate receiver?
The lack of a speaker, audio port and that J5 socket makes me think it is designed to be operated remotely. So this sits at the bottom of a radio mast but is operated from the tower some distance away. Curious if the Mic jack is TX only or more likely David Clark-style TX/RX for an avionics headset as this will be deployed in a very high noise environment.
General Dynamics CM-200 receiver
Like is it for sale
Wasn't planning on it, but email me bryan@bryanfields.net.
Can someone get back to me about buýing