[R-390] IF alignment questions and noise issue.

[Dennis Wade]

Good evening,

       Setting out to check alignment of the variable IF stages, and the
Y2K manual states to couple the generator through "Test Lead CX-1363/U" to
test points E209 and E210.

       I have an HP8657B, and my guess is the test lead mentioned above
isolates the generator from the receiver, probably through a DC block.  How
to you all couple a modern generator to those test points in practice?

        Noise issue:  The RF deck (that some may remember had shorted B+
cap) now seems to develop a "bacon frying" sound several minutes after a
cold start.  I've isolated the noise to the RF deck by unplugging J208 when
the noise is present and it completely goes away.  I've also swapped all
the tubes in the signal path with no change.

           Any ideas on how I might isolate the noise to a stage in the RF
deck?

 Thanks,

 Dennis

-- 
"If they trust you, it is an extraordinary privilege, and you simply can't
abuse it."
      - A. Alan Post  1914-2011.  California Legislative Analyst 1949-1977.

-------------------------
Dennis L. Wade
KG6ZI
Carmichael, CA