In article , "Henry Kolesnik"
writes:

Over the last few years I've acquired quite a few consumer electronincs pcbs
including TVs, VCRs, stereos, etc, so when I discovered that I needed a
tantalum to repair some test equipment I was going to salvage a tantalum. I
couldn't find one anywhere, so I assume they're too expensive or too
unrelaible for high end consumer electronics. A couple of the boards were
from my personal stuff purchased new. One example is a MGA Mitsubishi rear
projection TV that operated flawlessly for nearly 20 years of daily use.
Most of my test equipment comes from hamfests and is surplus after becoming
obsolete and non-operative in less than 20 years. That leads me to wonder
what the real story is behind tantalum capacitors.

Tantalum capacitors became a component item about 45 (or so) years
ago and originally favored in spacecraft and aircraft because they could
contain lots of electrostatic storage in a small space with ligher weight.
That was when PCBs were relatively new, quite new in spacecraft
electronics.

It hasn't been until the last decade or so that the cost of tantalum
capacitors has approached the level of improved electrolytic
capacitors of the same value. Tantalums are still relatively
expensive but they are good for SMT due to their smaller size;
its a trade-off between cost and overall system size in that case.

Inherent problems in tanatalum capacitors have been improved
since their initial debut as a component but so have electrolytic
capacitors and their manufacturing methods. One can purchase
FARAD-value low-voltage electrolytics now where once it was
not possible unless one had a room to put them in.

Len Anderson
retired (from regular hours) electronic engineer person