Tom, I render myself up to the firing squad! Give me the blind fold and my
last cigarette (Marlboro, please) and I will step right up. I want to thank
you for hanging in there with me and making me blow the dust off the books.
Just when I thought I understood all that crap, I realize there is still
more to it. I believe most would have not tried to hash it out till the
other got it. Anyway thanks, and maybe your gun will have the blank. All
kidding aside you wont hear this issue from me again. And to think, they
want to eliminate the code! At least I know it and pretty well. So I guess
if they do, the CW part of the band will be a retreat for the code-knowers.
I guess a lid that knows the code is bad enough, but one that doesnt is
worse. By the way are you going to Dayton? If so, the drinks are on me...HI
Now back to amps....When I built my power supply for my amp, I consulted
Bill Orrs radio handbook on power supplies. I wanted to be sure that I
would have as little DC voltage drop as practical from the supply, so I took
Bills word for it and had 120uf for my filter capacitance as he recommended
(from a chart) about 80 for the parameters of ecspected voltage and current
demand. Well I was disappointed with the results, I am loosing almost 1000
volts under full load, my HV went from 4300 volts to about 3400 volts.
Acccording to Bill,s chart that capacitance was to give about 5% regulation.
So just for the fun of it I switched the capacitance down to 64uf about
half, and the drop was still the same. Seems as though the value of
capacitance did not sffect the drop. Looking a Bills chart made me think it
would be worse. I am begining to think that is all to be ecspected. The
secondary AC voltage on the transformer is 3000 volts, so I guess maybe I am
lucky after all. I know the transformer is not suspect since it is a brand
new Peter Dahl 3000v/2A CCS rated transformer. I often wondered if broadcast
transmitter power supplies are designed to give the max. rated voltage (DC)
to the plate of the tube under load conditions, since they are under load all
the time, unlike amateur amps that are in standby most of the time, in which
case the no load plate voltage would be way over the rating thus killing the
tube. Any ideas on this? I would really like to see more of that dropped
voltage go to use if I could. Anybody else have this problem? If so what did
you do? I am thinking it just might be a fact of life. Hey does this RMS
stuff come into play again? Oh Boy......Thanks again...73 LOU
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