S-38 Questions about alignment.
"Bill M" wrote in message
...
Paul P wrote:
Band 2 is the problematic band. It covers 1.650 to 5 MHz. The 5MHz is
the oscillator set point. The padder is to be set at 1.8MHz and does not
even come close with the difference at the 5MHz Osc Trimmer error. This
band is aligned after the 455 IF, BFO and two higher bands are aligned.
After this band is the standard broadcast band.
The padder C11 on band 2 is a variable cap with a postage stamp (domino)
in parallel. I disconnected this parallel cap in hopes of raising the
overall oscillator frequency to align to 5MHz with no success. It barely
made a difference (no big surprise here).
The other bands align properly starting with Band 4, 13.5 - 32 MHz,
band 3, 5 - 14.5 MHz and last
band 1 broadcast.
Are you able to get the 5Mc point set ok?
Sometimes the solution is to fudge on the dial pointer alignment and see
if the other 3 bands can line up. However, if they are spot on now that
might not be the direction to go.
-Bill
I have done this before on other chassis. This chassis has hard stops at
the dial scale extremes. Moving the pointer will throw the pointer off
where it will not cover the band scale edge. This would be unacceptable on
this chassis.
I can not get the 5Mc aligned. It is fairly far off uniformly across the
whole band. All other bands are dead on the marks.
I am Climbing The Stairway to Heaven (the shop/shack) at this time. I will
report back later.
Thanks Bill,
Paul P.
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