After a lot of thought, I settled on the RCI Ranger, model 5Ø54DX, 6 meter multi-mode transceiver to use for the AM repeater receiver.

I purchased one of these radios, and was impressed with how well they sounded on AM, and how nice the AM squelch circuit worked.

The repeater has to operate carrier squelch in order to receive the old 6 meter tube radios, from the 5Ø's, and 6Ø's, so the squelch circuit has to be a good one.

Having a 6 meter transmitter on the receive antenna is handy for checking and tuning the receive antenna, and also when working at the repeater site, being able to talk back out on 6 meters, if needed.

I rack mounted the radio, and installed a test speaker, and I was impressed how easy that was to do. Bending 2 L-Brackets and cutting a snug fitting hole was about all that was needed.

Installing the carrier operated switch, and audio coupling to the receiver, also turned out to be easy. RCI had added a strip on print terminals for a accessory CTCSS decoder, and included a COS switch terminal. Of course it was the reverse polarity required, but I wanted to add a protection switching transistor in the line anyway.

The audio was picked up on the high side of the volume control, that way turning the control would not upset repeater audio levels.

The audio there is un-squelched, but that was no problem because the controller card mutes the receive audio.

The interface cable to the repeater has 2 wires shielded, Audio and COS. So, a simple stereo phone plug was used at the radio.

A .Ø2 mfd capacitor was added to the audio line to help reduce the AM hiss noise.

The Vertex VXR-5ØØØ UHF repeater was modified to power the RCI-5Ø54DX radio.

Vertex installed a barrier strip on the repeater for stand-by battery operation connections. It has a ground and both battery terminals, plus a open terminal, which I used to connect the RCI-5Ø54DX power wire.

Connection for the power wire was made through a in-line fuse holder to the positive 12 volt terminal on the Vertex power regulator board. That same fuse is also used to protect the fan, and the fan switching transistor.

I purchased a ICS Basic repeater controller for the 2 meter repeater, but it was lacking in remote switching capabilities which were needed for that repeater system, so I purchased a Micro-Computer Concepts RC-1ØØ controller for the two meter repeater, and used the ICS Basic for our 6 meter AM repeater.

Here the controller is shown with my home made mounting brackets, and in the next picture, my interface cable and connector.

Here the controller is shown installed in the VXR-5ØØØ repeater.

The ICS basic controller may be fine for a simple repeater system, but it was lacking a lot for use with a dual repeater system.

I have $135 invested it though, so I was determined to make it work.

I had to make numerous modifications to the circuit board for it to work properly.

It does OK, but some day I will probably replace it with the ICS Linker II.

Here is my schematic of modifications needed, to numerous to list, and my repeater adjustment steps.

Alignment of the AM receiver, and audio levels to the repeater were the last step.

   Click here to return to the 6 Meter AM Repeater Information Home Page