11 Dec
2010
11 Dec
'10
12:14 p.m.
List,
I've got a lovely old Lambda power supply here (linear +/-15, +/-5)
that uses an old Sprague screw-mount (Computerlytic) capacitor. It's
rated at 34000uF, 15WVDC. It's all dried out, so it needs
replacement.
It looks as if it's going to be difficult to find a working exact
replacement.
What in your experience works best in these applications? Plain old
"snap in" electrolytics? Anyone have any hints on making the
replacement fit the larger footprint?
As you know, you should get aworking voltage at least as high as the
orignial (but some say that runnign an electrolytic way beolw its rated
voltage will shorten the life), and about the same value. For a 34000uF,
I would thinkthat 33000uF would be fine (these are not close-tolerance),
or 47000 uF.
Some of the vitage radio crowd open up the old electrolyitic can, extrac
the guts and replace them with the modern replacementment capacitors. I
susepct, though that your can is too small to do this (it's not old
enough to me much larger than the modern caps.). But you might be able to
make use of the plastic moulding/terminals.
Once when I needed a screw-terminal electrolytic, I soldered suitable
nuts ot the termianls of a PCB-mount ('snap in') part and then fixed it
in place with the original terminal screws.
-tony