For the 6 meter repeater transmitter, my original intention was to use a Lettine, model 242, tube type, high level, plate modulated transmitter, built back in the 5Ø's. I used one back then, and it was a great sounding transmitter, with it's push-pull class B modulator.

Although this transmitter on the repeater would have been mostly for nostalgic reasons, it probably would have been a maintenance headache.

Well, I bought 2 of the Lettine transmitters, one for a spare, and had even restored one, and was about to rack mount it, when after having a after thought, and checking out the RCI Ranger, model RCI-5Ø54DX, 6 meter multi-mode transceiver, to use for the AM repeater receiver, I decided to use the RCI-5Ø54DX for the transmitter as well. Also, Having a 6 meter receiver at the transmitter site is handy when working on the repeater.

Well, the RCI-5Ø54DX only has a AM RF out-put of 6 watts, so while looking for a 6 meter RF amplifier to use with the radio, I discovered the price for the amplifier was about the same as the RCI-5Ø54DX-1ØØ, 1ØØ watt radio. I just wasn't sure it would be capable of continuous transmit duty cycle, but I bought one to try anyway.

The transmitter did over heat on continuous transmission, so cooling was required. After making the cooling modifications, I made the audio and PTT interface connections.

I installed a 4 pin microphone connector on the radio rear chassis for the repeater interface cable. Internal connections to the radio were to the radio microphone connector audio, shield, and PTT.

The radio was then rack mounted.

The repeater link receiver was then constructed from an old GE Master Pro UHF receiver strip from a commercial mobile radio. It was mounted to a rack panel, and on the other side of the panel I mounted a utility box to house the control circuits.

The receiver squelch level control was mounted on the panel, but the volume control was not installed, and the center arm connection was by-passed with a 16Ø ohm resistor to ground, and a 43ØØ ohm resistor to high side, as shown on the GE receiver connector.

The receiver is shown with the shield cover removed. I added a barrier strip for the 12 VDC power connections. The receiver is solid state, and crystal controlled.

Inside the utility box is the 1Ø volt regulator for the receiver, as well as DC fusing, and filtering. Since this picture was taken, I have added a time-out timer in the cos line, and a PL tone filter in the audio line.

Alignment was performed on the link receiver and audio coupling to the transmitter.

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