The scent of broken electronics

Given my history of dinking with electronics, I've burned every kind of component there is, many times over, both intentionally and accidentally. Because of this, I've acquired the ability¹ to identify the burning component by scent. They all smell like burning something, but each has its own specific character. Freshly sharpened pencil scent points to an overloaded potentiometer. A more earthy version is burning Ohmite (resistors). A scorched plastic scent is burning semiconductors. A hot metal/varnish/paper odor is an overloaded transformer. The same, overlaid with oil, is a motor. And a sour, alkaline smell is an electrolytic capacitor giving up the ghost (and its electrolyte).

While playing with the computer tonight, I noticed a worrisome odor in the air. Shortly, I was able to identify it as the scent of a dying electrolytic capacitor. Sniffing around failed to localize it, but I figured it was the computer (which was warm and spinning its fans), its power supply (also warm), the monitor, its power supply, or the external disk drive. I wouldn't be pleased by any of these things popping a capacitor. I also checked the shelf of electronics nearby, but they didn't seem to be the source either. I fired off a backup and shut down all the other stuff, just in case.

Then I stepped out in the hall, and the odor was much stronger. Hmm, the CFL in the hall fixture had flamed out a few months ago, maybe it's the replacement. I unscrewed it and gave it a sniff. Smelt like warm plastic, but not much else. Probably not that, unless the heat was volatilizing spew from the earlier failure, but it seemed a bit strong and sudden for that. Checking fizzygeek's room, the craft room, the bathroom, and the office yielded nothing useful. But the stairway to the kitchen seemed to point the way.

I told fizzygeek what was up and she said she didn't smell anything. But when she came out into the hall, she sure did! She checked around too, and agreed that the other rooms probably weren't the source. But what was?

I had replaced the kitchen lightbulb earlier in the evening, but it wasn't a CFL, as they didn't live long in that enclosed fixture. The previous bulb had been a 100W halogen, but when I ordered replacements (they're oddballs that can fit), they sent me 230W frosted ones by mistake. So I had put one of those in. Sure enough, the globe was uncomfortably hot. Our theory is that the spew from the failed CFL had been vaporized by the heat from the monster halogen, tricking me into ignoring anything that didn't contain electrolytic capacitors!

¹+1000 experience points!