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

[Barry]

Is it the sound of bacon frying or kielbasa frying?  If the latter, the the radio is completely normal.

Barry - N4BUQ

Sent from my iPad

> On Jan 17, 2015, at 9:05 PM, Dennis Wade <sacramento.cyclist at gmail.com> wrote:
> 
> 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
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