Re: A question about vacuum tubes

["Roger Kirk" <rogerkirk@ttlc.net>]

"SteveOrdinetz" wrote:
> Never understood why they switched the ground (ie chassis) lead of the
> power line.  This way if it was plugged in one way, the chassis was
hot
> when power was on, if you reversed the plug it was hot when the radio
> was turned off.

Check out the schematic of a typical radio:

http://www.geocities.com/wa2ise/

The chassis is not directly connected to the power line.  Although,
you can get a good hit through a 0.1 mfd cap.