Re: Replacing Electrolytics

On 2024-07-23 12:34, Cursitor Doom wrote:

HI all,
 Electrolytics of all values tend to fall under suspicion when any
vintage piece of equipment develops a fault. I'm just seeking a bit of
clarification on a couple of points:
 1) Axial electros are getting really hard to find new and even my old
spares bin doesn't have that many to choose from. I find increasingly
there's no option but to replace axials with radials. This results in
longer lead lengths than one would like, however. Is that likely to be
a problem generally speaking (ignoring the issue of whether they can
be accommodated on a board 'expecting' axials).

A good axial can have remarkably low ESL, down to 5 nH per inch or so, compared with 20 nH/inch for wire.  In boat anchors, you almost certainly don't care as much as in modern SMPS-powered boxes.

 2) Unused old caps ("NOS" stock). Is there any reason why one
shouldn't use NOS electros for repairs?  Assuming they can be reformed
and pass muster with an ESR meter, of course?
 Yes, I know ideally you'd want to use brand new caps, but with so many
cheap Chinese fakes around, I'm wondering if I'd be better off using
NOS caps from unquestionably high-end manufacturers. Even Mouser's
supply chain got infected with these a while ago!
 

Good caps last basically forever at room temperature.
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510
http://electrooptical.net
http://hobbs-eo.com