Quote:
Originally Posted by G6Tanuki
That's worrying!
I'm kinda glad that the vast majority of my gear here has steel or aluminium cases which would contain any 'internal' conflagrations.
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That's what reassures me about professional comms gear, too- it's quite conceivable that a waxed-paper etc. mains transformer could burn up (as did the one in my CR100 many moons ago....) but at least such an event ought to be confined better for longer than in a plywood box with a generously-ventilated hardboard back.
I once encountered thick black smoke and gawd-awful stink emerging from a Prowest "professional" colour monitor (17" low-focus tube), opening it up revealed that the black-case ITT tripler had spectacularly gone full Salvador Dali, slumping down from its place in the middle of the large vertical PCB into gooey stalactites and staying searingly hot for a worryingly long time after power-off and opening up. I assume that something had gone leaky within (multiplier ladder capacitor?), running hot enough for quite some time so as to melt potting compound and casing without being serious enough to cause the LOP series supply regulator to trip.
I've always been in two minds about potted components- yes, great if done properly for excluding dust and damp (and keeping proprietary secrets!) and pretty much essential with something like a TV tripler, but also hiding a few sins in terms of mediocre components, the failure of any one mandating a whole new module, and some rather hasty and sloppy interconnections- the sort of thing that left out in the open would earn one a justified bollocking, especially in the likes of mains filter modules.