> However, if the signal was at or near the noise level, then 2 db
> increase could make the signal more easily read. A 2db increase is
> like Christmas to someone using a single yagi for moonbounce.
Even 1dB is a huge increase when copying a signal near noise.
The error rate changes considerably here when working CW, when
I pick antennas that offer even 1dB more S/N ratio.
Most S meters are in the area of a dB or two at the low end of the
S scale, expanding as they get up around S-9 and they work fairly
well from that point on. My ICOM's are that was, as is my Yaesu
stuff. Almost no receivers are 6dB, most are 3 to 5 at the middle
scale. Most receivers actually tried for 5 dB per S unit, not 6. But
of course the calibration is often all over the place in different scale
areas, being much fewer dB per S unit at the low end.
Because we often see a 1 S unit change when it is only 2dB or so,
we often don't realize how much a dB or two actually means on
weak signals.
That's also why so many antennas have "supergain" or super F/B
on the air. Because people just assume an S unit is 6dB.
73, Tom W8JI
W8JI@contesting.com
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