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I use 330uf 63V caps for either the 180uf 40V or the 250uf 25V that
appear in the supply. I choose to use the higher voltage, rather
than stick with the voltages tek used because the ESR is lower for
a 63V cap, of a given value, than for a 25V cap.

I generally choose capacitors for volume when I have a choice.
Meaning that I will pick a higher voltage capacitor over a lower
voltage, if the case is closer to the original capacitor's size.

I don't like to replace a large capacitor with a dinky little one
that has the same ratings.

The rest of the capacitors are mostly 100uf 25V. They are linear
supply filters, and not to harshly used. Just use a good quality
105C long life capacitor in their place. I use 100uf 50V.

There are also 10uf 100V, and 3.3uf 350V caps on board, and the
bulk capacitors that filter the bridge rectifier/doubler that
runs the supply. They don't generally fail.

I use 330uf because it prevents confusion, and allows a bulk buy.
I typically use United Chemicon, but Panasonic makes a really
good cap too! Buy them from Mouser, not ebay. 330uf makes for a
slight improvement in ripple/noise, not that it is needed.

For what it is worth, I frequently found failures in the 180uf 40V
capacitors. Occasionally in the 250uf25V, and never in any other.

These supplies are a combination switching and linear supply.

The inverter regulates on the +5VD supply. Based on the 5V load,
it puts out AC to run all of the other supplies. These other
supplies are followed by linear regulators to gain the tight
regulation that Tek desired.

When you change out the capacitors, remove all of a given type
at once, then clean and solder in the replacements... Then go on
to the next value. A lot of folks pull them all, clean the board,
and then use the detail diagram in the manual to put them back...
This gets them into trouble, as some of the manual revisions have
the part numbers wrong. You can end up with a 100V cap in a 25V
location, and a 25V cap in a 100V location.... Works for a while..

One other thing to note, all of the polarized electrolytic capacitors
have their "+" terminal pointing to the same side of the board.

Always test your supplies out of the scope. The damage to the scope
from a defective supply can be too much to even contemplate.

-Chuck Harris