Ken Weitzel wrote:



Michael Black wrote:

Ken Weitzel ) writes:

wrote:

They didn't have diodes in 1941 of the kind you are thinking about

H. R. Hofmann


Hi...

I stand ready to be corrected, but to the best of my recollection
there were none at all - save mercury vapor tubes...


What year did selenium rectifiers come into use?

Though I can't remember the name, I thought there was also some
other non-tube diode that was in use.

There's little reason to expect either in a phone from that vintage,
but that doesn't mean there weren't such things.


Hi Michael...

Got my old memories going again... googled everywhere I could
think of and can't find any reference to any rectifer pre-dating
selenium.

Try googling for Copper Oxide rectifier. It was used in a A battery
eliminator
my Dad had in the 1930's

Then there were aluminum "wet" rectifiers used to get the high voltage DC
for some Ham transmitters.

Bill K7NOM


Gee, speaking of memories... anyone else remember the odor of one
of those selenium plate rectifiers when the load was shorted?

Yikes.

Your telephone... dunno if my message on the subject got lost in
cyberspace, but still think you should check the transmitter and
wiring.

An experiment? Plug it into a jack that's part of your house system
Leave it on hook; get someone else to pick up another phone and make
a call to a friend. As soon as they're connected and talking, you
pick up your handset - see if you can hear and talk to them.

Take care.

Ken