Eprom programmer for the MCM 2802 EEprom that was used in the CMC (Marconi) VHF portables.

For this project I used the PIC 16F876A. I found two of these portable transceivers at my local army surplus store. The specs were VHF hi band, 16 channel and 5 watt output.
Unfortunately one radio was missing its EEprom but was otherwise intact. My thoughts were there were enough spares to keep one radio working and if the EEprom died I would only be out of pocket $8 and a couple of evenings worth of writing some lines of code.
After some scouring of the internet I finally found a datasheet for the EEprom and frequency synthesizer. I wrote some C code for the PIC so I could get to the point where I could read out the memory locations from the EEprom. There were only two channels programmed and one channel was only set for receive so once I could reliably read three memory locations, I knew I was on to something. Superhetrodyne radios require different frequencies for transmit and receive, so two memory locations were used per channel.

Once I could reliably read the EEprom it was simple to reverse the process, calculate the synthesizer divisor value for the frequency required and then write it to the EEprom.

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