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May 16, 2024. Another Conversion of a Commercial Radio

Today's topic is a Conversion of the Hallicrafters FPM-300, a 1970's Hybrid Transceiver into an all solid state QRP Transceiver.




 






The Original FPM-300

Long story short about 7 years ago (maybe 9 years) I bought a deal on eBay -- a Hallicrafters FPM-300. That deal turned into a nightmare! The Original FPM-300 was marginal -- the unit I bought was beyond fixing.

It drifted, it oscillated, and the rubber band switch assembly kept getting out of sync. [There was a rubber band toothed drive belt that when you engaged the band switch controlled several switches.] Think of the crappy dial string mechanism on the S-38E.

In desperation I pulled the solid-state main board and S Meter and sold everything else -- net loss was $20.

Not willing to let well enough alone, I designed a QRP Rig around the Main Board and S Meter. This is what we are showcasing today.

Yes, this is an older project, but I thought in light of the Matchbox Transceiver episode on the recent hackaday this is right in line with those of us who like to roll their own. I doubt any of those lurkers could pull this off.

Yesterday I had the Ten Tec Model 150A on the air during my noon break from the Board and Care and checked into the Jefferson Noon Net. 

They have a question of the day. Boom, yesterday's question: Where do you buy your ham rigs. I couldn't resist -- my answer is that I build them, and you are listening to one right now. 

That got some responses like who builds radios these days? Very few of us... WYKSYCDS!


73's

Pete N6QW

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