on 3/5/00 9:37 AM, Lamb at k7fm@teleport.com wrote:
> Rich's original article in Ham Radio sounded plausible and conclusive. It
> would fix all parasitic problems. But, then, another article was published by
> Rich, who said that he had heard from a number of people who still had
> parasitic problems - so a better cure was developed.
When I was working on my 4-1000A amplifier a couple of years ago, I was
convinced that Rich's theory was right. I got into fights with many on the
reflector defending Rich. Yet when I read his literature, it just didn't
sit well with me. It didn't echo what I knew to be good science. Yet, I
figured that Rich knew what he was talking about and that his cures would
fix all my PA ailments.
So I put his ideas in place. One of his ideas was to install a resistor in
the B+ line called an anode fuse resistor. You can find this in his
literature. Also there was a ferrite bead around that same line.
My early amp design suffered from a LOT of problems include LONG anode
leads, etc. With Rich's circuit in place, I keyed up the amp. BANG! Oh
yes, I got a big bang all right. Took out the anode fuse resistor.
Hmmm...I thought. Rich's nichrome and resistors was supposed to cure
everything. I did it just like he said to. So I called Rich on the phone
and asked him what the problem might be. He had no idea. He just said that
it sounded like I had some sort of "event." I asked him about the fuse
resistor that blew. He couldn't figure out why it blew or would cause me
problems. He told me just to bypass it.
I had horrible problems until I redesigned the amp and rebuilt it from the
ground up. I had the nichrome in there but it heated up so much and Rich's
resistors would heat up to the point they would fail too! So I took it all
out and came up with the design you can see on my website.
Bottom line is that my amp was less stable with all the nichrome than it was
with the original design that was done by the SK who's estate I bought it
from!
Not even Rich understands everything about the circuits he claims will fix
your problems!
73,
Jon
KE9NA
-------------------------------------
Jon Ogden
KE9NA
Member: ARRL, AMSAT, DXCC, NRA
http://www.qsl.net/ke9na
"A life lived in fear is a life half lived."
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