January 9th 07, 09:13 PM
posted to rec.radio.amateur.boatanchors
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First recorded activity by RadioBanter: Jun 2006
Posts: 270
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What is BEST all-tube, general coverage receiver under $1000?Under $2000?
Don Bowey wrote:
On 1/9/07 10:32 AM, in article
l, "Stan Barr"
wrote:
On Mon, 08 Jan 2007 17:10:25 -0500, Chuck Harris
wrote:
Scott Dorsey wrote:
In article ,
Any reason why a 1N4007 wouldn't be happy in there?
Well, yes. When functioning as a demodulator, the diodes take the
Splitting hairs, if the diodes were in a ckt such as a "ring modulator"
where they functioned as a product detector, then they *were* a demodulator,
but most diode detectors were just envelope detectors.
How so? The diodes in a KWM2/2A are used as a ring modulator, and
work just as I described below. A 1N4007 would not be capable of
working that way at 455KHz.
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.
You could always try a "vaccuum state" diode such as a 6AL5...
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