Having standard electlytic caps on hand

[tkamiya]

As many bargain test equipment collector would know, electlytic capacitors are common failure items.  I'd like to stock most common values inhouse, but I can't seem to find name-brand pieces in a kit.  (like Nichicon or Panasonic)  Does anyone here do this?  If so, how/what did you source them?

[Berni]

It probably varies too much from equipment to equipment.

But these caps are usually not critical in value and the modern equivalents are quite a bit smaller in physical size. So you can often get away with a different one. Like a 100uF 50V cap might fit into the place of a 100uF 35V one. Or if the original one was 150uF you can probably replace it with a 220uF while still fitting on the PCB footprint.

You can have a look trough the service manuals of the equipment you have on your "wana buy" list to get some numbers.

More of a problem are weird shape capacitors found in some old equipment. Those axial elcos are often seen in old gear but are pretty rare today. The really big ones are the screw-down cans with wire terminals and such. Those big ones rarely fail but i seen some people open them up, gut it out and put a modern equivalent inside (since the modern one is 1/4 the size physicaly)

So id say as long as you have the common values at a decently high voltage rating of 35V or more you can fix most gear.