"Doug Smith W9WI" wrote in message
...
Honus wrote:
I'm new to the hobby, so please bear with me.

I picked up a Gene Scott broadcast last night on MW at 1615 KHz. Here's
the
...
I'm listening in Seattle, and I really don't think that I've DX'd the
guy
all the way from the Caribbean.

I wouldn't rule it out. Especially as particularly good east-west
conditions were reported that night.

The signal isn't constant; it faded out just like SW reception does.

Long-distance MW fades pretty much the same way.

I know. That's why I figured that it couldn't be a satellite transmission,
before I knew that MW doesn't come the atmosphere from space.

So my question is, just how did I hear this
broadcast? Scott uses satellites, but I imagine they're geo-synchronous
and
so (I assume) the signal wouldn't fade. Is that true? Is retransmitting
of
MW or FM band signals ever even done in the first place?

The satellite transmissions would be on microwave frequencies; MW
transmissions from space wouldn't penetrate the atmosphere to be
received on earth.

Thanks, by the way. That's just the sort of info that I was looking for.

And why did I
receive the signal at 1615 instead of 1610? Did I pick up a repeater of
some
sort? I have more questions, but I think that from the ones I've just
posed
that everyone can imagine what they are. Thanks in advance for your
replies.

My bet is that you were getting a spurious response to a powerful
shortwave broadcast. Your receiver will pick up signals on frequencies
other than the one to which it's tuned, if they're strong enough. I'd
bet you'd find Scott was broadcasting over a shortwave station somewhere
in the U.S. at that time.

This is a response that I received when I posed the same questions over in
re.radio.shortwave:

quote

Looks like a spurious response caused by your oscillator's third harmonic
and the radio's poor RF selectivity.

Assuming an IF frequency of 455 kHz, when the radio is tuned to 1615 the
local oscillator is running at 2070 kHz (1615 + 455).

The third harmonic of 2070 kHz is 6210 kHz.

With an IF of 455 kHz and an oscillator frequency of 6210 kHz, there will be
a response at both 6665 kHz (6210 + 455) and 5755 kHz (6210 - 455).

KAIJ carries Dr. Scott on 5755.

quote

I've also been picking up more than my share of images in the shortwave
ranges, so this seems to make some sense to me despite the jargon. g. I'm
ready to mail my Grundig back to China with a letter enclosed telling them
where they can send it from there. This whole shortwave/AM DX experience
has been extremely frustrating.