Date: Sun, 21 May 2017 01:53:03 +0000
From: Charles H <k4vud@hotmail.com>
To: "amps@contesting.com" <amps@contesting.com>
Subject: [Amps] new amp race
<I watched as EU ruined itself in contests with super high power big antenna
stations. Result seems to be they can not hear weaker long distant
stations.... so end up working each other in a band full of huge sigs.
<Seems now everyone everywhere is looking for at least 2.5 KW fighting low
sunspots and egos.
<Just like the arms race, the amps race results in all being "equal" again.
Before 200 w worked ok and most had 100 or 200 watts. Now seems many will have
at least 2.5 KW and results are about same, just sharper, wider elbows.
<The new amp race, Sad. 73, Charly
## is this on CW...or SSB...or both ? IMD on SSB and key clix on CW will
just make things worse. Big difference between the 200w ANAN 8000 with its
-80 dbc IMD3....and a $14,000.00 400w yaesu
FT-9000MP..and its abysmal -12 db IMD3 . Thats apples and oranges. Esp
when you now have the case where the anan –8000 xcvr is cleaner than say the
8877 amp. With the pre-distortion trick, now extended to any amp,
you can now correct for the amp..and improve its imd by 10-18 db...and thats on
top of the oem 8877 imd specs.
## Loud signals are an issue..with bigger amps and even bigger ants. But a 3
kw amp is only 3 db louder than a 1.5 kw amp. 3db is not about to trash the
bands. But toss in another 3db from bigger ants,
then we are up to 6 db louder. Then toss in sub standard IMD / key clix,
etc, and now you have a real mess on your hands..which gets even worse when
speech processing is used. Any processing will increase
the average level of the already lousy imd . Then we have the contesters who
TX on a 2.4 khz filter..then RX on a 1.8 khz filter.
The ARRL, etc, should get off their butts and get on a new crusade, low imd,
and minimal clix. Other than phase noise, I see no further improvements that
can be made on RX. RX is maxed out, focus on the
TX side.
## then we have the issue of the ambient noise on RX slowly increasing over
the years..... similar to light pollution for amateur astronomers. Some folks
are maxed out for ants already, they cant get any more gain
on their postage sized city lot. Noise is higher, so no wonder 1 kw is now
the new 100w.
Jim VE7RF
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