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Old June 3rd 04, 11:06 PM
Brian Reay
 
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"Harry - SM0VPO" wrote in message
...
http://w1.859.telia.com/~u85920178/

Over 200 projects, many with photo's and most with PCB patterns (BMP
250pixels/inch), even small PDF library and homebrew messageboard.

Latest project is DIY IF cans for valves (tubes) complete with on-line
calculators for the coils. Inc. Photographs.

Would be interested to hear whether anyone has any suggestions for
multi-gand tuning caps (100pf or more). I have been shoving tapered PCB
strips between other and it works a treat, but there must be simpler
methods. Also tried sponge/PCB sandwich with bolt compressor. Also works
well, but capacity limited. Ideas anyone? (Not interested in
varicaps/varactor diodes. They don't work so well with 250vDC!)


Do you want a variable or a preset? If a preset, have you thought of using
double sided PCB. One side un-etch, the other etched to give a series of
lands that reduce in area. Connect more lands to increase capacitance.

I saw the idea somewhere, so don't claim it as my own.

--
73
Brian
G8OSN
www.g8osn.org.uk
www.amateurradiotraining.org.uk for FREE training material for all UK
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www.phoenixradioclub.org.uk - a RADIO club specifically for those wishing
to learn more about amateur radio