Comments for "The "Wee Willy" RF Power Amp"

7th March 2012 18:23

clynton yarte wrote ...

I finally got willy on 20 meters. Your math was correct but my breadboarding techniques were not so it took a while. I built a tuner into mine (ab9dq) and assembled it with a very small 12 volt motercycle battery in a small luncheon box. ( My daughter had it to carry her barbi dolls which she outgrew) Small parts and kits went on winter vacation just in time to stall me off from getting the vn10's and the Bn Varacters. Did have all the cores so all worked out and is a joy to use. Thanks

3rd July 2011 21:08

Alan Yates wrote...


For the transmitter the only tuned bit is the output filter. Just start with a half-wave filter, Xl and Xc = 50 Ohms. 550 nH and 220 pF for 20 metres, 390 nH and 150 pF for 15 metres if I got my maths right.

For the receiver the two 10.7 MHz IFTs may not tune that high without some modification. The capacitances used suggest an inductance of about 5.9 uH, so the corresponding capacitances for 20 and 15 are 22 pF and 9.7 pF - starting to get small...

The LO should be easy enough, but it sounds like you'll be using a VXO of some description?



14th June 2011 07:15

clynton yarter wrote ...

I have been trying to build wee-willy for 20 meters and 15 meters switchable but can find no documentation for alternate band values. I've also mathed up a set of crystals to wack the extra sideband off. Help.

3rd June 2008 01:09

Bob wrote ...

I liked the documentation and the bread board techniques were interesting.

Good read.

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