Crystal Calibrator Question - HW-101

[John Mortlock]

>The crystal calibrator in my '101 decided not to work until the rig had
>warmed up for about an hour.  Applying heat from a hair dryer to the 100
kcs
>crystal before the warm-up period resulted in the calibrator working.
>Replacing the crystal has cured the problem, I usually let it warm up
>anyhow.
>
>Here's the question.  With the old crystal still installed a continuous
>faint tinkling noise would start shortly after selecting "cal".  The source
>of the noise was hard to pinpoint but I'm fairly certain it came from V17,
>the 12AT7 associated with the calibrator.  This happened whether the
>calibrator was working normally or not, but it had to be selected "on", and
>would stop as soon as the calibrator was selected "off".  Substituting a
>different 12AT7 in V17 made no difference.  Any ideas on what was causing
>the noise?
>
>Mike VE7MMH


The faulty crystal was probably making the noise......sounds like one of the
connections to the crystal (inside the can) has come unglued.  Connection to
the crystal electrode is usually made with conductive epoxy paste.

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