I have formulated a new theory which offers very convincing proof that the
traditional 'equalizing' resistors used with series-connected electrolytic
capacitor strings are NOT necessary. I realize that this contradicts the
prevailing wisdom, not to mention the design of hundreds of commercial amps
that have come and gone.
In lieu of just passing off what might be construed as idle speculation, I
have also done some meaningful practical work which supports my conclusion.
Specifically, I have been running 3 power supplies here over the last two
years with no resistors, one of them in my 'main' amplifier which is on the
air almost every day. To date, no sign of trouble. In addition, I have made
periodic spot checks of the voltage division between C's in each of the
supplies. Again, no unusual imbalances.
Now, I am preparing to make a public disclosure of my theory, which should be
of interest to anyone building medium to high power amps. Stay tuned for this.
Meanwhile, I would like to hear any meaningful anecdotal data which supports
the old belief: that without balance resistors, an imbalance in the leakage
currents can lead to destruction of some C's. There are plenty of cases where
the resistors themself failed, which guarantees a destructive imbalance (that
has happened to me). But has anyone ever seen or heard of a case where
'unequalized' capacitors blew? Unfortunately, few if any have ever dared to
even try it. The old myth was born many years ago and everyone is afraid to
question it.
Eric von Valtier K8LV
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