Scott Dorsey wrote:
Chuck Harris wrote:
Well, yes. When functioning as a demodulator, the diodes take the
IF frequency (455KHz), and the BFO frequency (453.65/456.35KHz), and
make audio. When functioning as a modulator, the diodes take the
audio, and the BFO frequency, and make modulated IF.

A 1N4007 cannot switch at even audio rates, let alone at 455KHz.

Okay, so we need a fast Schottky diode, with outrageously high breakdown
voltage. Something like that has to be out there, right?
--scott

Shottky, and outrageously high breakdown voltage don't go together.

What you think of as a normal diode is a slab of P, and a slab of N
semiconductor bonded together to form a junction. A shottky diode
is a slab of N semiconductor fused to a piece of metal. 100V is a
really high voltage for a shottky diode.

What you could do, is put some of your favorite diodes in a metal can,
and install them after your radio has died from EMP. Something which
will never happen anyway.

-Chuck

Chuck Harris wrote:

What you could do, is put some of your favorite diodes in a metal can,
and install them after your radio has died from EMP. Something which
will never happen anyway.

Probably not due to nuclear effects, but I have sadly seen lots of radio
gear destroyed by RF on grounds from nearby transmitters when antenna lines
failed. Not to mention my personal favorite, the radar that wasn't supposed
to be pointed toward the radio shack. The R-390 wouldn't be damaged by
that... hell, the front end probably wouldn't even overload....
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."