I recall my mother complaining that she felt a "tingle" when touching the stainless steel edge on her Formica counter top while opening the refrigerator. I was probably 10 at the time but I knew enough to run a ground from the BX cable to the counter edge. It was probably some leakage in the fridge compressor but it took a while for her to convince my father there was something wrong. This was in the early 50's so there were no polarized plugs.
Dan Kahn
On Tuesday, November 12, 2024 at 12:07:25 PM EST, wn4isx via groups.io <wn4isx@...> wrote:
I guess it's time to bring up "The All American Five" and AC/DC operation.
Parts of Detroit were 110V DC up until sometime in the 1960s. An aunt lived there and told me of the woes of getting a TV that worked.
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AC/DC radios most often had one side of the AC mains wired to the chassis. Which gave you a 50/50 chance of a hot chassis given non-polarized 2 conductor power plugs. Later units "isolated" the chassis with a capacitor, still deadly.
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The outer case and knobs were designed to prevent contact with the chassis.
My younger sister pulled Mom's radio off the table, shattered the case. I was told the throw the radio away, saved it, plugged in and it worked. I was 7 and touched the case. Our garage had a dirt floor and I was barefooted and got the urine knocked out of me. My father demonstrated the danger with a light bulb. That lesson stayed with me.
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So if you are restoring an All American Five (no idea why anyone would the performance was amazingly mediocre) be aware the chassis might be hot.
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Oh, the insulation in pre ?1970 Singer sewing machines was marginal and the case could easily be hot.
My older sister was shocked on Mom's Singer.
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And, lights are supposed the have the shell wired to neutral. Even with polarized 2 conductor mains connectors, do not trust the wiring!!!! Been bit once really good because I assumed "surely they wired it
properly at the factory." Nope. shell was hot, switch was in the neutral.
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Trust but verify applies to electronics as well as international weapons treaties.
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