Bill Murphy wrote:
>
> I have just completed several homebrew chokes, the question is what is
> the most effective way to use a dip meter to check these chokes for
> resonance.
First of all, be sure you are shorting the choke when you test it. You are
looking for series resonances, and shorting converts them into parallel
resonances which the dip meter can detect. Second, you have to check the choke
in place mounted in the amp. I found out the hard way that this matters.
Any dip meter is 'pulled' in frequency as you tighten coupling. To get the
exact frequency of a dip, reduce the coupling and keep readjusting the frequency
until the dip is barely perceptible. Then read the frequency (I use a counter
with a small link slipped over the dipper coil).
In my experience, there is usually one major dip at the primary resonant
frequency and then several smaller ones as the frequency is raised.
73,
Vic, K2VCO
Fresno CA
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