Thanks John for bringing a voice of "medium road" to the discussion. I
have learnt a lot from several professional rf engineers who are not
hams but understand high power amplifiers and are willing to pass on
some of their knowledge. Often the questions must sound kind of
stupid, but if you don't ask you won't learn!!
Incidentally the term "expert" was explained to me many years ago.
An Ex is a "has-been" and a "Spurt" is a drip under pressure - Hi.
John ZS5JF
----------
> From: John T. M. Lyles <jtml@lanl.gov>
> To: amps@contesting.com
> Subject: [AMPS] big or small amps, we're all hams
To: <amps@contesting.com>
> Date: 25 January 1999 10:07
>
>
> I realize that the heat may have passed, but I just wanted to comment
on
> one sentence that I read this morning:
>
> >>And then claiming that those who help the poor guy are just
building
> >>there egos is just absolute rubbish. Many thanks to guys like Rich
> >>Measures and John Lyles for doing some good old fashioned elmering.
> >
> >
> >Yeah sure, how many need 100KW Elmers that have zero revelence to
any ham
> >reality? Interesting reading but of no practical use at 1500W.
>
> The theory and practice of RF power amplifiers are identical, whether
it's
> 100 watts or 100 Megawatts. Pi networks, tubes, HV power supplies. It
all
> scales up or down. Ohms law always seems to work. Maybe corona creeps
in,
> but other than that.....
>
> I don't particularly believe that it is irrelevent, or I would not
have
> even mentioned what I build for my own career thing. I could just
sit here
> talking about my modified SB220 (it does work, and has the same mods
that
> most hams chat about here) but I thought something more interesting
to most
> amplifier builders would be other units, that use the EXACT same
> prinicipals as the 1500 watters. In 1978 I built/modified an 829B
amplifier
> on two meters. Yuk! But I learned from that old piece. Most of the
advice
> that I read from a number of very knowledgeble RF experimenters here,
I
> agree with. Which is exactly why I don't like to waste bandwidth on
the
> Internet complaining, or shooting down other peoples circuits. When a
less
> experienced amplifier builder asks a question, which may be common
> knowledge to 'experts', hams take the time to reply, and the
requester gets
> a variety of answers, to sort through. Usually, if one reads them,
there is
> a common middle ground answer than can be distilled. Funny, I never
even
> looked to see ham calls, or what the power level is. I do not try and
> police what someone will use RF power for, as a number of people here
use
> RF in their work. I have met a lot of people here, who do bigger RF
systems
> than 1500 Watts, and never mention it here. This appears to be the
only
> forum I have seen that covers all RF power amplification.
>
> The same tube/transistor manufacters apply. The same passive RF
components
> - ceramic caps, doorknobs, micas, vacuum variables, in bigger or
smaller
> PAs. I have learned a lot reading the AMPS reflector, and applied
some of
> the new knowledge to my own designs. I assume that others do the
same. I do
> not sell my designs for $$ here, nor to I recommend that all read
every
> word that I say and believe it.
>
> I am an advanced class ham, since 1971, a youngster compared to some
- but
> I am middle aged! I would have gotten extra class except for the 20
WPM.
> Maybe it will finally happen. Ham radio got me into RF, along with
working
> in a small town radio station back then. I am happy to have gotten to
do
> the things that i liked, and been paid for it. Everyone can do this
in
> whatever field they wish, if they really try. OK, enough said, i'm
sounding
> like one of those self-help talk shows, but I hate seeing people
bashing
> themselves and others over their opinions.
>
> 73
> John
> K5PRO
> (former WN4PRO, WB4PRO)
>
>
>
>
>
> --
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