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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