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-----Original Message-----
From: ham_amplifiers@... [mailto:ham_amplifiers@...]
On Behalf Of badgerscreek
Sent: Saturday, January 06, 2007 3:06 PM
To: ham_amplifiers@...
Subject: [ham_amplifiers] Re: God Complex

Extremely high power makes for an interesting experiment thats all. I
have not used my big box on real antennas for many many years.
However i still fire it up into a dummy load, and i still try and
improve its circuits. Does that make sense probably not

Anything above 1 kilowatt is very hard to justify on the needs of a
communications circuit. I would argue that its only the lower bands
where it may be of some help. Even then its hardly needed and is only
helpful in the case of jammers etc. Its shame having a high
electricity bill because someone else has a poor receiving location!

Very few stations these days have the ability to radiate the power
at the low incoming angles where it can do some good. With our greater
understanding of NVIS propagation, a good NVIS antenna like a
vertical yagi firing straight up in the air can just about compete
with a 20db amplifier if its a short range circuit

What gets most people unstuck running high power is either the ego
or using one of the modern ham radio exciters as a driver. Its very
hard to find a radio thats clean enough without generating snide
remarks about signal quality. Lets face it just about every radio
transceiver reviewed by the ARRL is as bad as the last bad lemon in
this regard. Now this is a problem even for those running legal power.

Most of us can build these amplifiers but few are willing to build an
exciter thats clean enough to match the excellent signal purity of big
amps. Maybe if the FCC changed its rules and allowed amplifiers that
can be driven with 100 milliwats like every military amplifier this
terrible situation might change.

When i get stations telling me in a sincere manner that a crapped out
old L4B makes 20 db of difference, imagine what can be expected if you
asked for a signal report on the difference that a 20 db amplifier
gives! If most stations used true calibrated S meter's they would not
be rushing out to build or buy a high power amplifier considering the
expense.

A case in point is the high power fax station somewhere in Germany,
listen sometime, Its on 13.381 or 382 DDK or DDH. It runs 20kw into a
vertical for weather fax. I can hear most hams better who are using a
low tribander than this station. This station is in an impressive
location and it uses a optimised antenna. Its a good propagation
beacon. This station essentially illustrates the futility of running
high power. When the band is open the signal is impressive, when the
band is marginal any ham with a decent antenna is heard with a better
signal strength. I would say most hams play it legal simply because
running high power in the places where most of us live is out of the
question.

Hams i think have extracted the maximum performance one can expect
out of antennas and propagation, there is hardly anything to prove.
In commercial shortwave link circuits this very same thing has
occured with shortwave planners, the shift in power is downwards not
upwards because even the military has too consider the economics of
high power. The power level is dropping steadily, when
once it was the norm for a military link station to run 40 kilowatts,
1 kilowatt with good antennas is the norm now. Most tactical planning
for long distance links have a target power range of .400 too 1
kilowatts of power.On SSB 4 kilowatts is about the maximum power used.
The Rockwell Scope HF system is an example.

Just my take, as others can justify the need for gas guzzlers so too
i am sure someone else can justify the argument for running high
power and think it makes sense. Now if the electricity was free and i
had a modern DSP transceiver that cancelled out the distortion and IMD
as i spoke i might change my view.


If i had the choice between high power and a hilltop location with
sloping terrain in all directions i would take the hilltop location
over the 20db amplifier any day. Better still is a saltwater island
with verticals, i then could run these stations on solar power and
achieve the same thing without contributing to global warming!


Greg



--- In ham_amplifiers@..., "Dr. Robert Bonner"
<rbonner@...> wrote:

You might have noticed I stayed out of the political discussion of
running power. Lets move on to the topic of the Religious Implications
of Running Power.

Steve, nice construction job.

Sincerely,
BOB DD

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