[Hallicrafters] sx-28 Silver Mica Re-cap kit

[Jim Wilhite]

Could it be the knob in not in the right place on the 
phasing shaft?  Do you see a notch and another 180 degrees 
opposite the first?  If so, put the cap at 1/2 engaged then 
put the knob back on with the 0 at the mark and recheck. 
You might not need to replace the micas.

Putting a signal generator through the crystal will check 
it, but remember you will see some loss of signal level 
through it.

If you can's find a peak for the crystal within about 1.5 Kc 
either side of the design frequency, then do as suggested 
before, remove it, disassemble carefully and clean with 
alcohol, then carefully reassemble.  Before removing it, 
either memorize the layout of the wiring, or take a picture 
of it, then when you reinstall, do so the way it was before 
you disturbed it.

73  Jim
W5JO



> Hi Everyone,
>
> I have rebuilt my sx-28 to sx-28a specs everything minus 
> the silver mica
> caps that are in the IF cans and the rest of the circuit 
> minus those that
> are in the RF section those were done when the RF section 
> was rebuilt. The
> radio works great except for The Crystal Filter. I am 
> suspecting that the
> silver micas are to blame seeing how that is the only 
> thing I have not
> replaced in the radio. All caps and resistors plus the 
> silver micas in the
> rf section have been replaced.
>
> So I am curious if anyone has a re-cap kit for the silver 
> micas minus the RF
> section?
>
> Thanks,
>
> Rob Copeland