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Old December 19th 03, 02:56 AM
Phillip Jockell
 
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James,

Try this easy way to make .55 microhenry coil:

Take a 1/2 watt resistor of about 1 meg ohm or more in resistance
(value irrevelant, just make sure it is above about a megohm),
put a tiny notch near one end parallel to the leads of the
resistor just large enough for 28 gauge wire to sit in (I use
a small pocket knife or a :Swiss file" whichever is closest at
hand when I wind a coil), solder a length of 28 gauge wire to
one of the resistor leads very close to the body of the resistor.

Now wind 15 1/2 turns of the #28 wire around the body of the resistor
and make a similar notch on the other end of the resistor and solder
the free end of the wire to that lead like you did the first. Keep the
turns touching each other ("closewound".)

Cut off the extra #28 wire and use this homemade .55 microhenry coil
in good health. It may or may not be EXACTLY .551 microhenries,
but it will be pretty close. The calculations come from a BASIC
program published in 73 Magazine years (decades?) ago and seems to
work pretty well.

Good look and post a report of how well this project goes.

Sorry if I made the explanation too simple if you already wind a lot of
coils, but I sometimes get carried away (gets worse the older I get...)

73,

Phil - N4GWV

I have a pixie 2 xcvr currently set for 80m. I have been wanting to
put it on the 20m band, so I found that I require a .551uH.

I assume that this would be a terribly easy coil to wind, but I've
never wound a coil w/ intention of achieving a specific inductance. If
anyone is familiar w/ the number of turns/gauge etc... for a .551uH
inductor, I would really appreciate that info.