[Elecraft] Help - which side of the trimmer cap is the "flat"side?

[Don Wilhelm]

Doug,

If the trimmer capacitors have one side grounded (as in the K2 or K1
bandpass filter trimmer capacitors) then a simple ohmmeter check will tell
which way they sould be oriented - the rotor should be grounded.  Check the
PC board to determine which side is connected to ground and then check the
capacitor to determine which terminal is connected to the adjustment screw.
The adjustment screw should be connected to the grounded side on the PC
board - that philosophy takes away any ambiguity in the particular form
factor of the capacitor itself - it will help eliminate any discrepancies
caused by parts substitutions.  Part substitutions are a fact to be reconed
with in todays world of parts selection.  The best solution is to be
familiar with the various possibilities that can exist  for the physical
implementation of a particular part.  Relying on any particular
characteristic such as color is dangerous practice because the manufacurer
of the part can change the color at will.  Be familiar with the markings on
components and rely on the 'standard' markings rather than an obscure
identification by color or some other parameter.

73,
Don W3FPR

> -----Original Message-----
>
> This is interesting.  If these are the same blue plastic trimmers as
> used on the K2, I put the smaller side on the flat side of the outline
> because it looked more like the outline that way.  The ceramic trimmers
> are round on the big side and flat on the small side.  The plastic
> trimmers are flat on the big side with slightly rounded corners but also
> flat on the small side which is also the protrusion away from the center
> of the adjustment screw which is similar to the protrusion on the
> ceramic trimmers.  Could this make a difference in the K2?
>
> 73, Doug -- K0DXV
>