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Old April 21st 12, 05:27 AM posted to rec.radio.amateur.boatanchors
Jim Mueller Jim Mueller is offline
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Default What kind of capacitors do I use?

On Fri, 20 Apr 2012 09:10:37 -0500, Ernie wrote:

My old receiver's IF wouldn't align and I finally traced it down to the
IF can. A grid dip meter shows the primaries and secondaries of each
coil are anywhere from 20 to 40 kc away from the design frequency
(460kc). The trimmers trim OK, but just not close to 460 kc. I can bring
each coil back to the IF frequency by soldering another small value cap
(100 pf or less) parallel to the trimmer. The capacitor sellers have all
sorts of variations and I am wondering if anyone can give me a
suggestion as to what kind would be the best to use for this
application? Thank you.


Grid dip meters are notoriously inaccurate. If the IF is 460 KHz, listen
for the meter's 2nd harmonic on 920 KHz with a broadcast radio before you
do something you can't undo.

It's especially suspicious that ALL the IF cans are off by the same
amount.


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Jim Mueller

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