Here are my 2 cents regarding low power.
My answer: it depends. My measure of "goodness" is whether
you can work most of what you can print.
I have always run low power. I don't even own an amplifier.
My current QTH is also very RF quiet and I probably have a
pretty decent receive set up.
Antenna systems can be left out of the equation because of
the Law of Reciprocity (no kidding, there is such an axiom in
antenna theory).
The two ends will have the same received signal strength no
matter what antennas are on each end, as long as the power
used at both ends is the same.
You can run a low dipole and he can run a 6x6x6. If both
of you run the same power, he is going to copy you with the same
signal strength as you copy him.
Thereby runs the crux of the problem. If he runs 10 dB more
power than you do, he will be 10 dB louder to you than you are
to him, no matter what antenna you use, or what antenna he uses.
So, if he is anywhere close to marginal print for you, expect him
not to be able to print you, especially if you have a better modem.
The only saving grace is that if his antenna is more directive than
yours, he has better spatial selectivity, in case of QRM and sky noise.
So, if he has a better antenna, his S/N ratio will be better.
It was a frustrating few months for me when I would tune the bands
and find FR5AB coming in the evenings, weak but printing fine. Calls
don't even get acknowledged. Finally, one evening, conditions
were especially good, and he went QRZ? when I called. After some
long repeats (and I mean long), he got my call (thanks, Roland!).
Another anecdotal story is the conditions between Phil, GU0SUP and
myself. For years, Phil and I have been chatting on email. I
would tune across stations working him, and I couldn't hear him
whatsoever. Phil tells me the same thing happens to him; he would
hear stations working me, but it is as if I wasn't there. This repeated
itself for years. Then during one contest, Phil used the GU0 club
station.
Better antenna, it seems. And the band was wide opened between us, too.
We finally made a contact. Both of us copied each other fine.
With low power, you will encounter that a lot. It could be frustrating
for impatient folks. If you are one of those, do yourself a favor
and get an amp. You might live longer that way. But if you are a
patient type who loves a good challenge, the feeling of accomplishment
could be even greater running low power.
At least one caveat to the above: if the other person is on a
deserted island, he will be able to copy you better you can copy
them. Almost guaranteed. In such a case, 100 watts is fine. That
has been my experience with such stations as 3Y0PI, 3D2CI and the
recent K1B.
In a sentence, if you run low power, especially if you have a nice
directive antenna or a quiet QTH, don't expect to work every station
you can print.
If you can't print them? That is when you need a better antenna or
you need to QSY to a better QTH, HI HI.
Oops, sorry for lengthy 2 cents. There is still only two cents worth of
content :-).
73
Chen, AA6TY
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