[Hammarlund] SP-600 JX17 rewiring, leaky chokes and transformers

[Tisha Hayes]

Quoted text

"While you are at this, test the filter choke for leakage to the case.
If there is any, do NOT follow the HSN article suggesting that you
mount the choke on unsulators. This is dangerous."

Thanks for the advice. I would never put a device that may have a case at B+
voltages on standoffs, I might electrocute one of my cats.

I have a Hipot tester that I use on the power transformers and chokes on
everything I work on (in one of my previous jobs I was a compliance engineer
testing products for UL, CE, FM and FCC certification, I own my own setup).
It is surprising how many old xformers are leaky but still in service.

For the same reason I install fingerstock on covers, put in a Corcom line
filters (even if it spoils the original look of a radio), and fab a
plexiglass shield over open terminal strips on the back cover where there
are any voltages greater than 50 VDC/AC exposed.

Tisha
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