RadioBanter - View Single Post

June 20th 06, 06:43 PM posted to rec.radio.amateur.antenna

K7ITM wrote:
wrote:
I guess I'm learning a public lesson but I'm going to post this as a
wrapup.

I figured out the problem. My inch of wire appears to measure about
0.06 microhenries.

1/(2*Pi*sqrt(0.06microhenries*165picofarads) ~ 50MHz

73,
Dan
N3OX

Yeah, you discovered why they* suggest using an array of values of
bypass capacitors, even when using SMT capacitors with "zero" lead
length, to do a good job of bypassing a supply over a wide frequency
range. And why even in ham construction literature from the 1950s they
talk about keeping leads very short for good RF construction.
. . .

And just one of the many reasons I keep saying that good RF measurements
are much more difficult to make than most people realize.

Roy Lewallen, W7EL