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Old May 24th 04, 06:36 AM
Mark Keith
 
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"craigm" wrote in message ...
"starman" wrote in message



If you need more capacitance, it probably means your stray capacitance is
very high and you reduced the number of turns in the loop (inductance) to
offset that problem and then added more variable capacitance to cover the
low end of the band.


In my case, it's because I want a real wide range. My stray
capacitance is low, but I do use only 5 turns for a 44 inch per side
loop.
I can tune up to 2300 kc using a single low value gang. I want AM-BC,
but I also need the 160m band up to 2000 kc. Thats why I design mine
the way I do. But I would always buy the biggest caps I could get,
even if I didn't need it. The price difference isn't that much. The
extra gangs could come in handy on a different loop...IE: one web site
has about 10 various types of caps...One they sell is multi-gang, and
will add to 1500 pf total...Thats the one I would buy, if I was going
to buy one from that page. Might as well get your moneys worth, even
if you don't need it all...:/ Use a switch, and you can use it for LW
down to a certain freq in addition to MW, but still have a low value
for the high end. I have some fixed caps to clip in to drop down into
longwave on mine. "to about 175kc". So all total counting those, I
cover from 175 to 2300 kc. Myself, I would never buy a single gang, if
I could get a dual for not too much more. I like free ones out of old
stereo's the best... If I didn't need 160m, I would use more turns,
and design for LW/AM-BC, instead of AM-BC/160m.. It would be slightly
more sensitive down low, using more turns. I may build another monster
loop just for LW eventually...MK