12 Aug
2014
12 Aug
'14
5:47 p.m.
On 08/12/2014 03:19 PM, Tony Duell wrote:
I beleive, strictly, the German diode is an OY3, not a
0Y3. Old European
semiconductors used the smae letters as the vlave code. The 'O' (not
zero) for the ehater voltage meant semicondcutor device. A is a signal
diode (so OA81, etc), C is a triode -> transsitor (so OC71 germanium
transsitor) and Y is a power diode/rectifier.
A web search brings up the 0Y3 germanium diode, so n0body's perfect...
_Very_ differnet? Yes, the electrode structure is
different, but in some
cases you can directly repalce one with the other. The characteristics
can be vey similar
Try running a 6L6 as a grounded-grid RF amplifier. Easy to do with the
EL34, since the suppressor grid is brought out separately. But I'm sure
that you're aware of many applications where that separate grid comes in
handy, such as suppressor grid modulation.
Anecdote...
Back when, the 12.6V heater version of the 807, the 1625, used to be
super-cheap as military surplus. You could get a carton of them NOS for
about $0.25 each. Some enterprising souls sought to built a GG
amplifier using them--the trick was to drill a hole in the base and fish
out and separate the beam-forming electrode from the cathode leads, then
attach them to one of the unused pins on the 7-pin base.
A friend built a GG final for his 160 meter rig using 10 of them in
parallel with the heaters in series, powered right from the line.
Interesting experiment.
--Chuck