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Comment by jzemeocala | Hacker News Reader

I would personally check that capacitor first before even touching the bulb.

That thing is well past the average shelf life for an electrolytic.

Probably is worth a check; I usually default to assuming that a good brand capacitor without any evident signs of corrosion, leakage or swelling is probably fine, but this is very old and also a higher voltage circuit than what I'm used to.

Since that looks like your normal camera flash circuit with xenon tube (the cap values are on point for one) I'd agree its likely the cap, unless there is anything visibly wrong with the flash tube.

That was my suggestion of what to try first when I responded to her original post on mastodon.

And he means check it without touching it with bare skin or unprotected eyes and mouth.

Who is checking capacitors by touching them to their eyes!?

It's not about testing it with your eyes, but about where the shrapnel might end up if things go very wrong.

I think he means that this is a high-voltage circuit, the same as found in xenon strobes and camera flashes. The 350V rating on the cap definitely confirms that.

If it is a flash type circuit, the capacitor will be connected directly across the xenon tube, and a separate trigger circuit will generate a much higher voltage to start the xenon conducting, and allow the capacitor to discharge it's energy and trigger the flash.

So, it might be the 350v capacitor has failed and is not storing enough charge to generate a meaningful flash, or the trigger circuit which is not generating the initial >5kV to get the xenon conducting.

Either way, i'd check the circuit before the xenon tube.

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