"RadioGuy" wrote in message
...
With the proper hookup you will get a tone---and the tone will be
adjustable
in frequency depending upon operator preference.

Ah, but then it wouldn't be a totally passive receiver. The OP is looking to
use only the passive receiver, not any add-ons or external sources.

Brenda Ann wrote in message
...

"RadioGuy" wrote in message
...
With the proper hookup you will get a tone---and the tone will be
adjustable
in frequency depending upon operator preference.

Ah, but then it wouldn't be a totally passive receiver. The OP is looking
to
use only the passive receiver, not any add-ons or external sources.


Yes well... I can't say the receiver will be totally passive but it won't be
too much more complicated than the basic crystal detector. At the most,
roughly speaking, three more component parts will be needed.

RG

"RadioGuy" wrote in message
...


Yes well... I can't say the receiver will be totally passive but it
won't be
too much more complicated than the basic crystal detector. At the
most,
roughly speaking, three more component parts will be needed.

RG



Demodulating SSB/CW is theoritically possible with an entirely passive
circuit. If there's a very high Q circuit at the proper frequency, it
will ring enough to give a good sidetone to CW and even demodulate SSB.
I have a couple of old single crystal filter receivers that can do just
that. Tuning is very touchy, and it takes alot of signal, especially
for SSB.

You'd need a proper frequency crystal, or a very, very, very, large
tuned cavity for starters. Being within the shadow arc of a powerful
SSB/CW transmitter would also be helpful. As a practical matter, it's
best done as a mind exercise.

Frank Dresser

"Brenda Ann" ) writes:
"RadioGuy" wrote in message
...
With the proper hookup you will get a tone---and the tone will be
adjustable
in frequency depending upon operator preference.

Ah, but then it wouldn't be a totally passive receiver. The OP is looking to
use only the passive receiver, not any add-ons or external sources.


Maybe he's talking about a bit of DC bias, and kicking the diode into
oscillation. There were reports of that sort of thing happening when
"crystal radios" were still pretty important.

Likely finicky, if one can get a specific diode to oscillate, and no
it's no longer passive, but it is simpler than the obvious solution of
adding an extra beat oscillator.

Michael

Maybe he's talking about a bit of DC bias, and kicking the diode into
oscillation. There were reports of that sort of thing happening when "crystal
radios" were still pretty important.

Now that you mention it, I believe that technique was used in some modern
device. Hmm... Possibly something in the UHF range...

Bill, K5BY

"WShoots1" wrote in message
...

Now that you mention it, I believe that technique was used in some
modern
device. Hmm... Possibly something in the UHF range...

Bill, K5BY

A tunnel diode? As I understand, that was supposed to be the "Next Big
Thing" around 1960. Didn't work out that way. But Heathkit did sell a
few "Tunnel Dipper" GDO type meters.

Frank Dresser

A tunnel diode?

That's it, Frank. Thanks.

Were they used in early TV UHF tuners?

Bill, K5BY

"WShoots1" wrote in message
...

Were they used in early TV UHF tuners?

Bill, K5BY

I don't think so. As I understand, they did work well at UHF
frequencies, but the circuits were very touchy to keep working. There
was alot of excitement for the tunnel diode in the old magazine articles
of around 1960, but it was quickly overshadowed by improved conventional
transistors.

Frank Dresser