On Wed, 4 Feb 2009 10:26:09 -0600, Paul Kraemer wrote:
>Double the actual output power rating of that fine L 4 or SB220 from 1000 w
>to 2000 w will only increase your signal strength on the receiving end by
>3db, 1/2 s unit.
As others have noted, S-meters are NOT well calibrated. Those I've taken the
time to measure with a calibrated generator are 6 dB from S8 to S9, but more
like 3dB/S-unit at S5 and below.
More important is how humans HEAR. While it takes a change of about 10dB for
overall sound levels to be heard as "twice as loud" (or half as loud), a
signal that is buried in the noise can be a lot easier to copy if its level
increases by only 2-3 dB.
One example: during the recent 160M contest, I was QSYing up and down the
band to call DX stations, often without retuning the amp. When I went from
the bottom of 160 up to 1880, power output dropped to about 700W. For most
QSOs that was not a problem, but there were a few stations I wasn't getting
through to. I slid down a kHz or so, tuned up to full power, came back to
the DX frequency and made the QSO. That was only 3dB, but it made the
difference more than once.
Yes, it's ALWAYS good to squeeze every dB you can out of your antenna
system. I've done that by using RG11 on my high dipoles, and by adding more
radials to my 160M vertical. If a dipole is low, it's often possible to pick
up a dB or two by raising it. And so on.
73,
Jim K9YC
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