For the people who know me personally, it should come as no big surprise that I love Amateur Radio. I got my General Class license two years ago and I’ve got an MMR-40 in the final stages of construction. So it was with some excitement that I recently got my hands on this antique single-sideband transceiver.
I have been able to find almost no information about this model of radio, except that it was probably build by Donald Stoner in the 1960’s or 1970’s. Instead of a tuning knob, it has quartz crystal oscillators that lock it to a specific frequency. This has the main advantage of being simple and reliable, but the disadvantage of limiting you to whatever frequencies you happen to have crystals for.
When I opened up this radio for the first time, I saw it had only one crystal (it has slots for up to four) and the frequency was just below the 40 meter band. Fortunately, I was able to buy some crystals online, enabling me to operate in the 75/80 and 40 meter bands.
Putting in the new crystals was just a matter of removing the bottom panel on the radio, which reveals the crystal filter (that large rectangular metal piece in the far right corner), the crystal control sockets (one of my new crystals is plugged into the first slot), and the…channel control modules?
This is problematic. As I understand it, each channel needs a pair of these, for receive and transmit, and I only have one set. I would like to use all four crystal slots, but finding more of these channel modules will be difficult to say the least. I doubt my local Radioshack has carried these within my lifetime, if they ever have.
I will probably have to build my own; a prospect I look on with some trepidation. Reverse-engineering these parts doesn’t look too difficult, though there is some danger of damaging them. Making the new parts fit, though, will be a chore.
Well, I suppose it’s all part of the charm of amateur radio. Hams have been building and modifying their own gear since the birth of the hobby, and that’s part of what I love about it.
If anyone has more information about this radio, be it user manuals, schematics, funny anecdotes, pictures, part sources, or anything else, please share.
Also share some of your commas with me because I seem to have run out.