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Old January 9th 07, 12:45 AM posted to rec.radio.amateur.boatanchors
Chuck Harris Chuck Harris is offline
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First recorded activity by RadioBanter: Jun 2006
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Default What is BEST all-tube, general coverage receiver under $1000?Under $2000?

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