[Boatanchors] CG-512

[WA5CAB at cs.com]

Barrie,

I agree with Carl.  Assuming the primary impedance choices are 50, 200 and 
500 as stated previously, I can't come up with a logical scenario that matches 
the resistance readings.  The secondary does.  Or least it seems to.  Assuming 
the two windings have the same number of turns, the higher resistance of one 
could be explained by it being the outer winding.  It would have a longer mean 
turn length and therefore higher resistance.  The "F" markings probably stand 
for Filament.  If you were using it with a zero balance tube, you would 
connect one to each side of the modulator tube filaments and use a center tapped 
filament transformer.  But with the 100TH's you'll probably have to use fixed 
bias so tie the two together as you said earlier.

One way in which to reverse-engineer the primaries would be to attach a 
variac to one of the secondaries and measure the AC on the primaries.  That will 
give you the turns ratios.  Square that for the impedance ratios and then see 
whether you can figure a combination that comes out in the ratio 50/200/500 or 
near to that.

In a message dated 1/10/2009 7:03:49 PM Central Standard Time, 
barrie at centric.net writes: 
> >About all I can find is that the specs are the same as the PA-512 which
> >is the standard version of yours. Still no connection info. However that
> >model was around for several decades going back into the 30's.
> >
> >Perhaps Bunker of Doom has one catalog with info.  Or look in old
> >Handbooks, thats a fairly standard line to PP grids item.
> >
> >Those measurements make no sense.
> >
> >Carl
> 
> Carl:
> 
> I just checked the resistances again using a different meter.  Same results.
> 
> Could I have a defective transformer?
> 
> 73, Barrie, W7ALW
> 

Robert & Susan Downs - Houston
wa5cab dot com (Web Store)
MVPA 9480
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