On Mar 22, 2:28 pm, wrote:
On 22 Mar, 12:17, wrote:

I'm wondering what the expected lifetime is for electrolytic
capacitors in recent years. I'm sure temperature and operating
voltage play a role.

It varies hugely. Some have lives of thousands of hours, some of over
a century.

Ripple current also affects them.

Capacitors failng to do the job are often not down to bad caps, but
rather bad design with insufficient margins.

I think some just fail with age and lack of use too, then fail when
voltage is reapplied. Last week i repaired a portable cassette
recorder with extremely noisy hissy output with the programme material
almost inaudible. there were two caps, a 220uF and 100uF 16v I think ,
across the output stage of the amp. Both were within operating
voltage, looked fine no bulging etc. but this machine had been sitting
for decades without use.