[AMRadio] You must see this.

Robert Nickels ranickel at comcast.net
Mon Jan 11 21:03:32 EST 2010

On 1/11/2010 6:53 PM, Todd, KA1KAQ wrote:
> Wonder what those rectifiers in the back are? They look to have
> nickle-plated tops, or maybe it's just a reflection. The front tubes
> look like 80s.
He says they are "DCG1/250" rectifiers.  Aren't they just about the 
coolest tube...uh, I mean valve - with that directly heated coiled wire 
filament and actual "plates"?   Look like they came straight out of 
Edison's lab!

The main rectifiers (flashing blue MVs) are identified as DCG 4/1000s, 
but they look like 866s to me.   The amp runs on 220 V three phase 
power, that's why there are six of 'em.

He says the preamp and driver are EL34 and in a comment on one of his 
videos says the outputs are QB3, 5/750, "together they make 1500 watt of 
dc power and 1 kilowatt for the speakers".  Quiescent current is set to 
50ma per tube, full power is 250ma at 3000 volts.  And no fan!

Maybe some one who is familiar with European valve numbering can clarify 
what these valves are in US nomenclature.

73, Bob W9RAN

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