Hi all,
tantalum caps seem to be too expensive for consumer-grade equipment.
They contain pricey material - silver and, of course, tantalum, so
making them cheaper is impossible. AFAIK they are widely used in
military-grade equipment, where the price is not an issue. Their main
advantages are a longer life (they do not dry out nor leak) and a
bigger temperature range (frost resistance).
About using cheap parts in consumer electronics: At least 80 percent
of failures of certain types of TV sets were caused by dried-out
aluminum caps. The good practice when repairing these sets was: first
check all electrolyte caps by adding a good one in parralel. It was
successful very often.

BR from Ivan

In article , OK1SIP
writes
Hi all,
tantalum caps seem to be too expensive for consumer-grade equipment.
They contain pricey material - silver and, of course, tantalum, so
making them cheaper is impossible. AFAIK they are widely used in
military-grade equipment, where the price is not an issue. Their main
advantages are a longer life (they do not dry out nor leak) and a
bigger temperature range (frost resistance).
About using cheap parts in consumer electronics: At least 80 percent
of failures of certain types of TV sets were caused by dried-out
aluminum caps. The good practice when repairing these sets was: first
check all electrolyte caps by adding a good one in parralel. It was
successful very often.

BR from Ivan
The observations are consistent with the view that electrolytic
capacitor reliability decreases within a short time most other
components have failure modes that take a much longer time to reach the
end of the bathtub.
--
ddwyer

I read in sci.electronics.design that OK1SIP
wrote (in ) about
'Tantalum caps.', on Wed, 21 Jan 2004:

tantalum caps seem to be too expensive for consumer-grade equipment.
They contain pricey material - silver and, of course, tantalum,

No. We used quite a lot of tantalum 'bead' caps in consumer audio and TV
until we found the problems they have and we could get aluminium
electrolytics 'with no added salt', so they didn't leak and were much
more reliable. I still have some boards with them fitted.

The problem with Al caps drying out is mainly that people let them get
too hot. They were rated at 75 C or 85 C *max. ambient*, not
'temperature rise'. It's still a problem; we have 'designer' set-top
boxes with no ventilation, and service people put 130 C rated Al caps in
them as replacements; 105 C rated is often not good enough!
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk