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Hello,
I am back working on my Philco 84 restore and have a question about the power connection. I am going to add a polarized plug and wanted to know if I should run the hot side to the volume/ power switch as it currently connected or to the Bakelite condenser (transformer coil) where I am going to replace the existing capacitors with .001 uf X1-Y2 safety caps.
Bob
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Yes, it is always better to have hot on the switch. The cap placed on the opposite side is also good as due to the inductance of the primary (the tubes not conducting) on the turn-on, it will not pull spark when the switch is closed or open.
The sch calls for 0.015uF, so the popular value being 0.01uF, this is what I use for Y-caps.
You could also experiment with adding X-cap across the line (I always do it with a parallelled 1M reisstor). In case you have interference to suppress.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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That model 84, at least the four tube original from the 1930s, is an AC set, so I'm not sure why you would need to add a polarized plug to it. The power switch only switches one leg of the power transformer primary, and it doesn't really matter which leg is switched.
Posts: 16,476
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That is also true.
I just prefer to have switch on the hot in general. For a stupid situation like, say, there is a weak transformer leak to chassis, and it is always connected to the hot.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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