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Old 11th Jan 2011, 2:01 pm   #3
Coastwatch
Retired Dormant Member
 
Join Date: Feb 2010
Location: Berwick-upon-Tweed, UK.
Posts: 113
Default Re: Battery-less audio amplifier

The one I built in the 60's, a PW design I think, had the power supplied from a LW Xtal set with 4 diodes (can't remember which [OA91]) as a bridge rectifier.

Now does anyone remember the WWII spy transmitter that used no power supply. I will start a thread on that one soon.
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