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Old June 10th 05, 11:51 PM
Brenda Ann
 
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"Jeff" wrote in message
ups.com...
It might kill him if he touches the radio chassis when the rectifier
fails. The stink is from the gas seleniums give off when they short.
Since the rectifier is in the power supply (across the AC line) and has
the full line voltage across it as long as the line cord is plugged in
(whether or not the radio is on), if it shorts it will likely put the
chassis at line potential (until the fuse blows). Another way the guy
could do himself in in a big hurry would be to touch the chassis of an
AC/DC radio and a grounded surface, such as a radiator, both at the
same time. Just a couple of thoughts.


I've never seen a radio where the rectifier is across the AC line. Half
wave rectifiers are in series with one side of the AC line with the cathode
feeding into the B+ line (thereby isolating that side of the rectifier from
the other side of the AC line by the tubes and electrolytic capacitors). Now
then, if a bypass or electrolytic were to short out completely, that would
put the AC line across the rectifier. At any rate, I've never seen a
rectifier that was energized whether the switch was on or not (save some of
the cheap SS stuff where they keep the PS live and switch the radio out of
circuit).