Here are some pictures of the newly built KM4GHM repeater that I am about to put on air in Lebanon.
I have gutted a Motorola MSF5000 so we could use the case and some of the mounting brackets to hold parts for a completely different machine.
The current version is using a pair of Tait T2020 UHF transceivers for the transmitter and receiver, an ID-O-MATIC IV from Hamgadgets, a Mirage UHF 100w amplifier, 75a wall mount power supply, and a small pass-notch duplexer. All of this fits easily inside the case from an MSF5000.
I’m also really liking the IDOM. It was easy enough to put together, has really good instructions for setup and programming, and it’s really easy to program with Windows using puTTY (though I haven’t figured out how to program with mac yet). It seems to be a highly capable repeater controller for the $39 price tag. It keys the transmitter when the receiver detects a signal, handles a courtesy tone, IDs, Beacons, time out timer and time out penalty, and fan relay. I’ve connected the RX and TX audio directly to each other, so they are bypassing the IDOM altogether with just a jumper running to the board for the ID audio. I’m handling the encode/decode tones in the transmitter and receive radios. The only issue I have found with the IDOM is that when I was powering it via the 12v power supply there was a strong hum behind all audio coming through the board. This was cured by powering it through the USB port. It’s possible that the issue was my power supply or the wire I was using.
We’ll be driving the amplifier with just enough power to get between 40 and 50 watts out so as not to overwhelm the duplexer and to help with heat inside the repeater.
It’ll be attached to a Comet GP9 antenna (9.9db gain on UHF) with 100′ of LMR400 when it goes on air.