I completely disagree!
My first amplifier project was at age 16, shortly after I got my general
class license.
I modified (and extensively at that) a amplifier that was homebrewed by
someone else. I removed the choke in the power supply, converted it from
tube rectifiers (3B28) to 1N4007s that I bought from James Electronics,
built a tuned input circuit, built my own high voltage probe with 1 megOhm
resistors and used it with my Radio Shack range doubler voltmeter, and then
used it extensively on 40 meters SSB on 7235. AND lived to tell about it!
But then again, I'm very confident around high voltage.
And this was in 1975-76.
73
Jim W7RY
-----Original Message-----
From: sm0aom@telia.com
Sent: Friday, January 06, 2017 1:18 AM
To: amps@contesting.com
Subject: Re: [Amps] Decline of homebrewing?
This was written almost 50 years ago, and gives some food for thought even
today:
"Homebrew Kilowatt
Dear 73,
Did you ever write an article that you later wished
you had not written? I have written several. The latest
is the 6KG6 KW amplifier appearing in January 73.
The third paragraph states, "It is assumed that the
ham who starts out to home brew a kilowatt is not
embarking on his first construction project".
You wouldn't believe the letters I have received from
neophyte hams, who, by their very questions, reveal
that they have never built anything at all. So suddenly
they decide to build a KW with 2000 volts on it.
I sincerely hope nobody gets electrocuted as a result
of my article.
I belive you need a good article entitled, "If you
want to get your feet wet, start at the shallow end of
the pool". Then go on to describe a good linear (or
other amplifier) that has a supply of less than 500
volts. Go through it piece by piece and explain what
the parts are for and why they have to be within
a certain size range. The stock question about the
above amplifier was "What's the size of the capacitor
between the plate and the pi-network? This is noted
in at least ten places in every handbook in the land.
A ham who doesn't comprehend even vaguely, the pur-
pose and limitations of a dc blocking and rf by-pass
capacitor, has no business building anything as lethal
as a KW final,
R. D Baird W7CSD
Klamath Falls, Oregon"
73/
Karl-Arne
SM0AOM
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