Sam Goldwasser wrote in message
...
So my trusty scope is acting up.

At normal and low intensity, there is a chopped appearance to
the trace at a few hundred Hz. It's variable and at times,
increasing intensity also causes change in focus, and/or the
intensity doesn't go as high as it should.

I assume a problem in the HV.

Thanks for any info.

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I only have the manual for the 465 , not B variant.
But assuming ps similar I would suggest a problem leading to ripple on the
unreg 120V supply rail (bridge, caps )feeding the EHT oscillator/driver
circuitry or problem in that oscillator circuitry or of course, wallectomy
time, problem in the EHT step-up transformer


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Diverse Devices, Southampton, England
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