Trimmer capacitors - backwards mounting

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Trimmer capacitors - backwards mounting

Don Wilhelm-3
Folks,

I have had two private emails already asking about what happens if the
trimmer capacitors are mounted backwards.

The real answer is - NOTHING! - well almost:

If you attempt to adjust them with a metallic screwdriver, the extra
capacity created by the tool and your hand will add to the circuit capacity
and you will find the adjustment seems to change as the tool and your body
position changes.  When the adjustment is connected to ground as is normal,
the trimmers can be adjusted with any screwdriver that fits the slot, but if
they are mounted backwards, an insulated tool must be used - and I for one
have never been 100% successful using a metallic screwdriver covered with
electrical tape - that helps, but takes great care and a bit of trial and
error before things are adjusted right.

As long as a non-metallic tool is used, you will notice no difference.

By the way, the trimmer capacitor in the wattmeter section of the KPA100,
KAT2, KAT100 and the series tuning capacitor in the KX1 have both ends above
ground, so a non-metallic tool must be used to adjust those.

I got a small set of ceramic adjustment tools to make life easier, but the
green adjustment tool supplied with the K2 can serve the purpose just as
well even though it is a bit more flexible than a really good tool.

73,
Don W3FPR
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