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Default QUESTION: FM Stereo Sensitivity

In article , Meat Plow wrote:
On Tue, 06 Nov 2007 10:20:48 -0800, EADGBE wrote:

I went to a garage sale recently and couldn't pass up an old Technics
SA series receiver in great condition. (A Technics SA series receiver
was my first bit of halfway decent stereo equipment.)

The receiver's FM tuner works great and sounds very good, but I can
only get the "FM Stereo" indicator light to light up on one station,
even though the signal strength meter indicates VERY strong FM signals
on almost every station all across the FM band.

I only have one of those little clear-coated two-conductor wire FM
antennas hooked up to it right now, but if I recall correctly, that
was all that was needed to get FM Stereo on virtually every station in
my area.

Could something be weak in the FM tuner circuitry, or do I need a
stronger antenna?


Need to align the stereo section of the tuner which requires some
equipment that generates specific signals.

And whilst I'm at it, what is the functional difference between the
two 300 ohm FM antenna terminals and the grounded 75 ohm FM antenna
terminal, besides the obvious difference in resistance?


75 ohm is coax type connection, 300 ohm is twin lead. The often have a
common input terminal.


75 is commonly unbalanced, or uses ground reference. I do have some 72 ohm
balanced lead next to me, and there is no shield. You can buy balanced
shielded however. I used to use some 300 ohm shielded lead for a TV antenna
way back. One of my tuners I started to use, which I bought of Ebay, is slightly off
tune, and you have to hit mono to get good reception. It can also affect the stereo
and muting thresholds.

greg