Hi folks! First-time radio builder here, and I've just completed my DCR build! (Pic and video below...)
I have a background in electronics, but mostly audio, digital, video games, tube guitar amps, etc. My only previous experience with radio was a restoration of a small AA5-style radio for a friend. I first saw this project featured on w2aew's site and it seemed too fun not to try. First go with Manhattan construction, too, and I really enjoyed it!
Though I built everything on one board, I did test the modules one by one as I went. I did build and test the audio amp "left to right" instead of the other way around, because I have enough bench gear that I could check as I went without relying on the speaker.
My audio amp build did tend to motorboat turned about half-way up, particularly with no RF input. It was easy to see on the 'scope that the DC power bus was the feedback path. Threw a couple 470uF on there and that pretty well quenched it. In addition to the coil former, I also 3d printed a battery clip and and bracket for the volume pot.
Tuning turned out to be pretty delicate/twitchy, but I am getting better at it. I opted to start with the 28 TPI steel screw after reading some things on the blog. I will probably end up moving some of the windings off the tuning former to try and improve this, and/or investigate a fine tuning option.
I am running right now with a 33' wire out my basement window, up the side of the house, and partway across my flat roof, plus a 16' counterpoise on the basement floor. Will probably get more ambitious with a feedline to a vertical wire in a tall tree in the backyard away from the house this upcoming week.
No license or callsign yet, but I've definitely got the bug with this project, so am reading the materials and hope to take the exam(s) soon!
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Congratulations Frtiz -- Welcome to the Hall of Fame!
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Great work Fritz! Love how clean it is. Can't wait to hear you on the air.
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