Thread: Winding coils
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Old December 9th 03, 08:47 PM
Steve Nosko
 
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Gents,

Another practical consideration. Another area where caution is
advised--paralleling bypass caps. In solid state Power Amplifier design,
such a configuratin can cause problems because there is a point where one is
above self resonance and acts like an inductance in parallel with the other
cap which is still capacitive-- thus, resonance and no bypass. Been there,
done that. We put a small Z in between. Frequently a small bead or
resistor if possible.
Seems there is an equivalent problem with series inductors.

--
Steve N, K,9
d, c. i


"Bill Turner" wrote in message
...
On Sun, 7 Dec 2003 19:17:08 +0000, John Woodgate
wrote:

This is a 1920s problem. Just as you parallel capacitors of different
type, electrolytic, metallized foil and ceramic, to get a wideband
component, so you put inductors of different construction in series to
get a wide band component. You can wind them all on a bit of wax-
impregnated dowel if you like. (;-)


__________________________________________________ _______

That will work, no doubt. My point was that it takes some serious
engineering and careful testing; you can't just wrap some wire on a form
and expect it to work correctly across a wide range of frequencies.

--
Bill, W6WRT