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Old November 7th 09, 04:27 PM posted to rec.radio.amateur.boatanchors
Michael Black[_2_] Michael Black[_2_] is offline
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First recorded activity by RadioBanter: Mar 2008
Posts: 618
Default Hammarlund SP-600, help me to identify which version is...

On Sat, 7 Nov 2009, Dave J. wrote:

In om on Sun, 1 Nov
2009 15:08:24 -0800, in rec.radio.amateur.boatanchors, 'Richard Knoppow'
wrote:

The JX-17 was intended for diversity operation and has
connectors for the IFO (second conversion oscillator)


Just out of interest, how long has diversity encoding been around? I
thought of it as relatively modern, and I've only read about it from the
POV of digital signals. Is there anywhere anyone'd recommend for a bit of
research? Something semi chronological would be nice.


It goes back to the thirties, at least. Hallicrafters had a diversity
receiver back then, I have no idea how many were sold.

There was an article in "Ham Radio" decades ago about diversity and
specifically about that Hallicrafters radio. Looking at an accumulated
index, I think it was the April 1980 issue. But, there was a history of
Hallicrafters in the same issue, and that one (from the same accumulated
index) is supposed to be in the Nov 1979 issue, which makes more sense
since for a long time the magazine devoted the November issue to
receivers.

Michael VE2BVW