[AMPS] 3-500z going dead?

[Peter Chadwick]

Kevin says:

	> The brand new fluke showed only 4.6 volts.  I then
	>liberated my old Simpson 260 from the garage and it alse reads
4.5-4.6
	>volts.  Oddly enough if I rewire the amp back to 120vac it shows
4.9-5.0
	>volts on the filament.  Each leg of the 220 line is exactly the
same >voltage (117.5) so whats up with that?

Dunno! But is the AC neutral tied to ground at all in the amp? If so, it's
possible that you could have equal line to neutral voltages, but not
necessarily line to ground. I'm not quite sure how these things get wired
over there; our wiring regs make you keep neutral and ground separate, and
they only join at the service entry to the property. Are the two primary
windings of the transformer exactly the same? I assume that you have two
primaries, in series for 220 and shunt for 117. I presume that you measure
fil volts with the amp not transmitting - especially with the fluke.
According to my DVM, my PA tubes have -200 on the screens when transmitting,
and +300 when not! Moving coil meters tell a different story..........

GL

73

Peter G3RZP


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