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Philco 90 No Spkr or Output Transf.
#3

OK, will do. I simulated having a 10 uF cap right on the input to the power supply filter (right onto the 80 filament), then 1.5K then 22 uF to ground, then another 1.5k and then another 22 uF.

The simulator showed very low ripple like 40mv pp.

I suppose I could back off the 22uf's to 10 uf's and increase the
ripple a bit but decrease the overall capacitance that has to charge.

I figure with a total of 3K resistance in there it should limit the current
that the 80 has to supply upon power up.

I should check in my simulator what the peak current is under these
conditions and make sure it is not too high.

The 80 Rect datasheet gives a typical capacitance of 10 uF for a
capacitor input filter so I figure that part is OK. It's the additional
R's with C's that I suppose could be a problem.

Herb S.


Messages In This Thread
Philco 90 No Spkr or Output Transf. - by hsusmann - 04-16-2014, 04:01 PM
RE: Philco 90 No Spkr or Output Transf. - by hsusmann - 04-16-2014, 05:03 PM



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