Michigan Mighty Mite's

 
 Above is my bevy of Michigan Mighty Mite transmitters. It is the simplest transmitter I have ever built that gives such good performance. I have one for each of the following bands: 160 Meters, 80 Meters, 40 Meters and 30 Meters. Each are crystal controled and built with what ever parts I happened to have on hand. Each of these have a 2N2219 Transistor and each puts out about a half a watt. They all seem to be really clean and do not exibit the common chirp problem that many simple transmitters. As you can see no expense was spared in providing a first class Chassis. One of the simple modifications was to add a LED power output indicator on each of the antenna output lines, so I could tell when the transmitter was working. I use an external antenna change over switch and my ICOM-706MKIIG as the receiver. So far I have worked Radium Springs, New Mexico (about 20 miles from me) on 160 Meters and got a 549 signal report. It is a lot of fun to see just how far you can go with the "minimalist" transmitter.
 Further information about this little transmitter can be viewed by clicking HERE

 A 20 Meter Version



A 20 Meter version was first built by Harry KC5TRB of Tulsa, OK. He emailed me the changes to the basic Michigan Mighty Mite and they are as follows: The Coil is #20 enameled wire , 10 turns total with the tap at 4 turns from the bottom. He also changed the 27 ohm resistor to 15 ohms and the 10 Kohm resistor to 18Kohms. The Varriable Capacitor was changed to a 3.5pfd to 60 pfd. (Not too critical as you need about 1/3 to 1/2 of it to resonate the circuit on 20 meters. The crystal in this one is 14.060 and I get about 350 milliwatts out with no key clicks or warbles. So the word is now out. Harry renamed it to the 20 Meter Tulsa Mighty Mite. Since he made it I think it is only fitting.

UPDATE: Got an email from Harry on 1/9/2007. He hung his 20 meter Tulsa Mighty Mite with
a KID cw IDer outside and let it run. He received a QSL from Doug KK6D in Riverside, CA
a distance of 1200 miles. Not bad for only 350 mw and a wire antenna. Harry also miniturized the
transmitter into a 35 mm film can for this beacon project. I think it is also getting ready for a future ballon ride. If you would like to see what he did ...
click here


 Hope to catch some more of you Michigan Mighty Mites on the air out there. If I can help answer any questions, give construction hints, or help with parts and substutions please contact me at dhassall@zianet.com

Good Luck

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