Electronic smoke tracing

[Infraviolet]

Is there any common method for finding out where the "magic smoke" escaped from, when the circuit it came from still appaers to be working?

I've been working on a slow speed sinusoidal BLDC driving circuit, (a commercial 2A 12V wall wart, no lithium batteries or high current supplies, powers my circuit setup which takes the form of a buck converter like system which recirulates a a much bigger current at lower voltage within the motor's coils) and whilst running it noticed a hint of something that looked like magic smoke drifting in the beam of a desk lamp, no sign of exactly where it came from. And I got a faint whiff of that unmistakable burnt component smell. I cut the power, tried wiping my finger around various components for an "ouch", no heated spots. I gingerly turned it back on again, and it all seemed to run properly, no more smoke visible.

But I'm sure it was electronic component smoke I saw and smelled.

The circuit is presently on a stripboard (veroboard) with some short single core wire pieces running between different sections.

I don't have a thermal camera. Any idea how I might diagnose where the smoke came from, so I can correct the circuit design so it won't happen again, potentially becoming a proper "magic smoke-->dead components" incident if it does. As I said, everything seems to be working still, so I can't just locate a dead component.

Thanks

[Bud]

Could be an electrolytic capacitor vented its stuff from below. Can be difficult to locate unless lifted.

[Manul]

If magic smoke shows up, but the device still works, most of the time it's resistor. Look for discoloration.