Quote:
Originally Posted by Philips210
I think tantalum bead capacitors are not to be trusted and agree that modern low leakage low ESR electrolytic capacitors generally make good replacements.
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I would totally disagree with this....unless the electrolytics you are referring to are radial through hole parts or axial parts. Most modern electros are surface mount now, in most modern gear. This is a very big problem.
I would rather a board was populated with 50 vintage Tant bead capacitors, either through hole parts or surface mount Tants, than even one surface mount electrolytic !
When a Tant fails (photo attached of a supposed reliable yellow one that recently smoked in one of my SG503 generators) it announces its presence a lot of the time with smoke & that familiar smell. Or it just goes electrically leaky.
When the surface mount electrolytics leaks electrolyte, its a game changer (as they ALWAYS do if you wait long enough) the faults they cause are diaboloical and complex with inter-track leakage, corroded films in surface mount resistors and corroded tracks.
With inter track leakage, you end up with what amounts to a new unique circuit configuration. Because of this, fault characteristics can appear impossible or bizarre and not relate to the circuit architecture of what you are trying to repair. This can make fault finding much more difficult and time consuming. I know, I had inter track leakage issues due to leaking electrolytics in a Tek scope and a video monitor, it is not a good party.
Whenever I see surface mount electros I replace them with Tants, and I'm happier with that and more confident, even knowing that Tants (especially vintage ones) can fail as they do and smoke up the room, but generally they fail
destroying themselves, not causing gross destruction to many square centimeters of PCB and parts around them.