[Collins] 516-F2 PS Question - some numbers

[Al Parker]

Hi Folks,
	Well, after reading all the replies, and checking my inventory, I 
decided some numbers might be interesting.  So I took measurements using 
the Tek 7xxx scope and Fluke meter, with different capacitor values 
across the filter choke in the HV secn of my "bench" 516F-2 that's the 
subject of this whole exercise.  I had replaced the electrolytics and 
the bleeders in this supply some mo.s ago, maybe over a yr ago now.
	I read the peak to peak 120 cycle ripple value on the scope, not super 
accurately, and took the AC rms reading with the Fluke.  The values 
match roughly with the math.  HV read with the Fluke.
	I set the line input to give 6.3 vac on the filament line, and that 
corresponded to about 110vac input.  (LV was 374v)
results:
             HV    ripple, scope     ripple, Fluke
no cap     1014     8 v p-p           2.8 rms
0.041 mf    904     8                 2.5
0.05 mf     875     6                 2.2
0.074 mf    856     4                 1.2
0.1  mf     866     3                 0.7

	Make your own conclusions, it's interesting that the HV went up a bit 
at 0.1 mf vs 0.074, with less ripple. I did not make actual capacitance 
readings, just took stated values.  The ripple's wavefor became more 
distorted as the capacitance increased, at low values just a notch, but 
pronounced double notches at 0.1mf.
	I think I'd be happy with the factory value, or a bit more, in the 
0.075 range.
thanks to all who responded,
73,

Al, W8UT
www.boatanchors.org
www.hammarlund.info

"There is nothing -- absolutely nothing -- half so much
worth doing as simply messing about in boats"
Ratty, to Mole