Thread: r8 vs. r8a
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Old January 21st 07, 12:03 PM posted to rec.radio.shortwave
craigm craigm is offline
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Default r8 vs. r8a

Geoffrey S. Mendelson wrote:

Michael Black wrote:
And one reality is that "sync detectors" came into common use in
relatively
low end receivers. Before the Sony 2010, I can't think of any receiver
that had a built in sync detector. The advantage in that and other low
end receivers is that it does allow "narrowing" the selectivity without
the cost of a filter. It is cheaper to use some passive components and
an IC than to add a good IF filter.


The "sync" detector of the ICF-2010 was originaly a gimmick. Sony took the
old, tired, IFC-2001 design, clean it up, improved the reception and
microprocessor, added air band, but still needed something to really make
the radio different than the other 2001 derived radios which were coming
onto the market.

By the time they were designing it, AM stereo was a commercial failure in
the U.S. Sony had a warehouse full of custom AM decoder chips and no where
to put them. One of their engineers figured out how to convert them to
a sync detector and put it in the 2010.

It was a great success.

Geoff.



It probably wasn't hard to convert as the Kahn-Hazeltine method was ISB.

From: http://en.wikipedia.org/wiki/AM_stereo

"The Kahn-Hazeltine system worked on an entirely different principle which
independently modulated the upper and lower sidebands separately to
differentiate the difference in program material. If an AM station were
broadcasting AM stereo using the Kahn system, stereophonic sound could be
partially enjoyed by tuning two standard radios slightly to either side of
the station, one to the right side of best tune and one to the left of best
tune. The best way to experience the most stereo separation however was by
using an AM Stereo tuner with appropriate circuitry for decoding the Kahn
system."

Just set the decoder to the mode and pick the left or right output.