ARGH! Where can I get .1uf 200V electrolytics?

[Paul Perry (Frostwave)]

My other hobby is restoring antique radios. I've done a lot of old 50's tabletop radios that are built this way, no transformer. Usually the neutral goes to the chassis, and the hot goes to a dropping resistor, filtercap, etc.

There's the problem, if you connect it to a power socket wired backwards, or use an extension cable wired wrong, then the active goes to the chassis.. and to anyone touching the chassis. I'd only ever use one of these with an isolation transformer, AND the earth wire going to the chassis. I can remember touching the inside of one of these deathtraps as a child.. and active is *230V* here in Australia, not 110!
(I was even younger when I grabbed the frayed wire going to an antique wirless speaker.. what I got was the wire to the speaker field coil, which doubled as a filter inductor in the 385V DC power supply  :shock:   :shock:    :cry:

[Fret Wire]

Like Paul said, earth (green) to the chassis. Kinda redundant, but insures the polarity will be correct.....as long as the wall outlet is wired correctly.

[vfr800fiman]

Like Paul said, earth (green) to the chassis. Kinda redundant, but insures the polarity will be correct.....as long as the wall outlet is wired correctly.

I disagree with this statement. It doesn't seem right to tie the ground wire to the chassis (again, we are speaking about transformerless designs). You would then be connecting both the neutural and ground to the chassis. Maybe an EE could chime in here as I'm an ME.
That's essentially like jumpering the neutural & ground together on your wall power outlet, must raise hell with all the other devices plugged into your house wiring

I guess I forgot to mention that I always use a polarized plug (USA) on my radios of this type. You can't plug it in backwards that way.
Like Paul said, it's pretty common on these old radios to get a "tingling" sensation when you touch a knob if the hot and neutural are reversed :shock:  

Glenn

[vfr800fiman]

Maybe we should move this thread to the "Off topic" area?

[puretube]

"tingling" maybe in US;
SHOCKING is a reality in Australia & Europe!

[vfr800fiman]

"tingling" maybe in US;
SHOCKING is a reality in Australia & Europe!

Yes, I've inadvertently touched 230VAC, and after waking-up on the other side of the room I just sat there a while thinking about it :lol:

[Fret Wire]

Maybe we should move this thread to the "Off topic" area?

For What? The last thread of this type stayed in the main section.
http://diystompboxes.com/sboxforum/viewtopic.php?t=33010&postdays=0&postorder=asc&start=0

Using a polarized plug doesn't guarantee anything more or different than a three-prong if the home/building wiring is not correct. They are both means to insure the user gets the polarity right. You're still at the mercy of the building's mains wiring. With a polarized two prong plug, you're still in deep trouble if a component fails, and the chassis goes live. The three-prong provides a path back to earth.

RG's suggestion of a isolation transformer is still the best way to go.