| While chasing some QRM on LF, the ordinary wall wart which powered my receiver died. I replaced it with a switch mode power supply which I had previously used with a small computer. This turned out not to be a good idea for two reasons:
- The new PSU generated even more interference, which seemed to have a fundamental frequency of 25 Hz (half that of the mains),
- More importantly, I got a tingling sensation when I touched the metal case of the receiver. Although my AC voltmeter did not indicate that the case was live, my trusty electrician’s screwdriver with built-in neon bulb lit quite brightly.
This PSU is going to the electronics disposal unit at the local waste management site. Even if the stray potential is not a simple electrical hazard, it could easily provoke an involuntary movement resulting in damage to some piece of equipment. I seem to recall the late G3VA reporting in the Bulletin that he had lost an AVO 8 that way.
John F5VLF
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