First of all, it has been a LONG time since I last posted to this blog. Much has happened, both before and during the lockdown, but here we are,

That’s the “Back to Blogging” part, but what, you are probably saying to yourself, is “the Joy of Oscillation?” The oscillation in this case refers to a radio signal being generated by an oscillator circuit, and the joy is the satisfaction of building something yourself, and seeing it work. The term was coined by Bill, N2CQR, in his Soldersmoke blog and podcast.

The build in this case was the Michigan Mighty Mite design, a crystal controlled transmitter, making use of a television colorburst crystal at a frequency of 3.57954 MHz, which just happens to be in the Ham Radio 80 Meter Band. Thank you goes to the folks at Soldersmoke for providing that crystal.

There is no one right way to assemble the Michigan Mighty Mite. I decided to base my assembly on a method described by George Dobbs, G3RJV (SK) in a series of books for youth that I enjoyed back when I was in 8th or 9th grade, using a board, and making connections using screws and fender washers rather than solder.

The base board was one my wife picked up at the local hobby store. The transformer was wound with magnet wire around an empty pill bottle. The variable capacitor is held in place with a 3-D printed bracket thanks to my son.

I hooked the antenna port (white cable, upper right corner) to a dummy load for testing, tuned my main rig across the room to the colorburst frequency, turned on my workbench power supply, and tapped the key. Much to my satisfaction, I heard a tone from my receiver. Adjusting the variable capacitor (the only control on this transmitter) caused the signal to strengthen and the tone to be clearer. I was experiencing “the joy of oscillation!” I was now, as Pete, N6QW would say, a member of the “Colorburst Liberation Army.”

I’m looking forward to trying this transmitter on the air. Two things need to happen before that takes place: first, I will need to build a low-pass filter in order to clean up spurious additional signals from this Mighty Mite. Secondly, I need to get my antenna replaced, as it decided to self-disassemble over the winter, and I need to do some tree trimming before the replacement goes up.

This project was a lot of fun. I had started to build this several years ago, and then life intervened. It was satisfying to dust off the parts and start up again, and all the more so that it worked on the first try.