Question on preheating old A/V equipment to protect capacitors

[jannab]

Hello,

I have a terminology question I am hoping someone can answer. I am translating from French an interview with a French video editing technician who maintains and stores obsolete audio/visual recording equipment. He is asked this question about the obsolete equipment:

Do you think it is necessary to connect them from time to time if they are not used for a long time?

He answers:

We will preheat a machine if it has not been used for a long time. We simply turn it on, to avoid a capacitor "claque" (French word). Then we fully clean before putting a tape inside.

"Claque" in French can mean slap, but it can also mean "worn out" or "fatigued." My question - for a machine from the 1930s-1970s, what is the most likely capacitor phenomenon he is referring to?

Thanks so much!

[budm]

Re: Question on preheating old A/V equipment to protect capacitors

http://www.circuitspecialists.com/bl...o-or-amplifier

http://fullnet.com/~tomg/tuberep.htm

http://conradhoffman.com/capchecktut.htm

[jannab]

Re: Question on preheating old A/V equipment to protect capacitors

Thanks very much, budm. Very helpful.

So it seems to me the guy is probably referring to reforming the capacitor, as in the first link you provided. Does that sound right?

Thanks.

[budm]

Re: Question on preheating old A/V equipment to protect capacitors

Yes, slowly apply voltage and monitor the current draw AFTER SAFETY CHECK of the whole unit first.