>
> I don't understand why putting the 25 Ohm resistance in one transformer
secondary
> lead wouldn't serve all needs, turn on surge (cap. charge), control arc
and shorted
> condition overload and current limit under shorted rectifier or capacitor.
> Like the 10 Ohm 1/4 Watt resistors in series with the plates of 6X4's they
are fuses.
> --
> Ron KA4INM - He who attacks the fundamentals of the American
broadcasting industry
> attacks democracy itself. -- William S. Paley,
chairman of CBS
>
> ************************************
The 25 ohm resistor functions both as a fuse (in case of extreme overload)
and partly a current limiter, e.g., when the capacitor bank is charging.
Putting it in the transformer secondary lead is probably okay, but I'd
prefer to put it after the diode rectifiers, but before the filter
capacitor. Note that this resistor, while desirable, doesn't protect
against an arc or short circuit, since
a fully charged capacitor bank can momentarily supply hundreds of amps of
pulse current into a short circuit. Thus one also needs some protection
after the filter cap, such as the Drake .82 ohm 2W composition resistor used
in the L4B.
73,
Jim W8ZR
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