At 06:56 PM 7/22/98 -0400, John Nelson wrote:
>
>Message text written by Jon Ogden
>
>> I once made the same comment between 1KW and 1.5KW and you should have
>seen the comments! Yes, they say, it DOES make a difference. I don't buy it
>though.<
>
>It's hard to understand the reasoning, since 1.76dB doesn't remotely sound
>like enough to make an operational difference in an HF pile-up situation.
>So my guess is that any improvement would be psychological in origin rather
>than actual. But maybe if you feel better about your station and have more
>confidence in it -- however unsoundly based -- you'll do better. Is the
>consequent enhancement in station performance due to your power increase or
>your change in attitude? Either way it's real enough.
>
>Amateur radio stations are operated by humans, and humans are highly
>irrational in certain important (and largely unconscious) respects. So it's
>probably wrong to assert that only pure engineering issues such as dB
>increases are involved, although the wider arguments aren't really
>pertinent to this reflector. Personally, I tend to feel there's some danger
>of making the error of logic usually called "post hoc ergo propter hoc"
>(loosely expressed as "A happened after B, therefore A was caused by B").
John, Jon et al -- as one of our politicians aptly said, describing the
process of appropriating money for government spending, "a billion here, a
billion there, first thing you know you're talking serious money." Or in
this case a serious improvement.
I'm a contester, and in contesting you scrounge for a dB here and a dB
there, because in the aggregate, over 48 hours, even a dB has been shown to
discernible difference in the number of QSOs made. You are earlier into
(for example) Europe when the band opens... your signal stays in longer as
it closes. More 100 watt/low dipole stations hear you. Etc, etc. But
even more to the point, if you can find 1.76 dB somewhere (without making
your signal less intelligible, which is what I believe must happen with
turning up your 10000MP), it's 1.76 dB you didn't have before. Replace
your feedline with CATV hardline, and you find another 1-2 dB (depending on
band). Stack a second yagi 5/8 wave from the first, and acquire 3 dB in
the main lobe, plus the ability to shift your main lobe up and down to suit
conditions. And so on, and so on.
In my own station, I've chose to stay with an SB-220 at 1200 watts, rather
than go to a "full legal limit" amp, because the dB/$ ratio isn't
favorable, not because the difference isn't real, and cumulative. Each
time I look at a station improvement, I look at dB/$, whether those dB are
gained on receive as well, and whether there are other factors that play
into the mix (for example, directivity causing a reduction in the effective
signal-to-noise ratio). That's why this year's increment is a second
element on 40 (converting my C-4 to a C-4XL).
73, Pete Smith N4ZR
n4zr@contesting.com
"That's WEST Virginia. Thanks and 73"
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