Leaky/Intermittent Tantalum Capacitors

[pamphonica]

Notably if they are used as decouplers where there is a significant amount of current available they can be very nasty. I've had one, fitted across the main reservoir in some professional kit,  actually catch fire. Had this happened in service (in an unattended area)  rather than on my bench the results could have been truly horrible.

I have had a significant number of tants catch fire in Tektronix test equipment of the 1970s era, especially the tiny 500 series rackmounted modules.  These tants first glow brightly then emit smoke then go phut!  Easy to fault find subsequently why the voltage rail was zero, though!  If they have already self-immolated, the easiest way to find them is a low-range ohm-meter like the ToneOhm etc.  It's so simple to slide the test prods along a power trace and hear the tone frequency peak as you pass the exact faulty tant.

I have always replaced them with modern 105 degree decent quality electrolytics - much better nowadays as power rail decouplers/smoothers.

Happy days...

Jeremy