Hi, I guess I am from the "show me" state. Many have been writing in about
errors in the the ARRL manual and Bill Orrs book. I must admit, I use these
books to learn from, I am tend to believe what they say, since I don't know
of my own knowledge. I am not saying here that there is not mistakes, I am
sure there is, but what I am saying in effect is that since I learned from
these books, some of what I learned is wrong, so I am really screwd up. I
read with great respect what Tom and Carl write here. But I am presently in
school learnig AC theroy,(maybe I am getting bad info here too) and I was
taught the following.....Residential AC line voltage is 120 V RMS.
The peak voltage is 1.414 of this or about 170v. The term RMS is synonimis
with the term effective voltage. Effective voltage is the vltage that will
"heat a resistor".
I take this to mean, in my own words as the voltage to use to calculate
power. I may be wrong, but we always use RMS value AC voltage to calculate
power in an AC circuit and NOT peak or crest voltage. I am taking these
thoughts over to my power supply that sags so badly under load. My
transformer is 3000 volts on the secondary my studies tell me this is RMS
voltage. Ok now, so I rectify this volltage and I used a capacitor input on
my supply, and now I have 4300 volts DC. This value is oddly 1.414 times my
secondary RMS voltage of the tramsformer and therefore leads me to believe
that it is some kind of "peak" voltage derived from the transformer secondary
voltage of 3000. But I think think DC has a peak value as does AC casue it
doesn't alternate. So if in effect this voltage of 4300 has to do with the
peak of the secondary AC winding of the RMS value of the transformer, and if
RMS and effective is the same, and if effect voltage is the only "heating
voltage" then how can I ecspect any more power from the supply than the
heating effect that the transformer will give me. I read here that the 1300
volts DC more than the secondary of the transformer will indeed add to the
power. I wont say this is untrue, but I dont see it. There ahve been
reports here that capacitor input filters indeed work good, but I cant get
mine to work like that. So if there is bad information in the books I read,
someone please tell me where all this pwer is and goes. I know one thing for
sure, The KVA that the transformer can produce cannot be less than the power
the amplifer can make and vice versa. Thanks....LOU
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