Can you identify this button?

arhi writes:

I have some old (very old) KONTRON DMM 3002 bench top digital multimeter… there is a button on the thing that I have no clue what it does…

So if you look at the pic, the button in question is the pressed one, or if not clear which one is pressed, the one with “–” sign.

When I switch the dmm to the — the display count from 0000 up approx 1 per sec, the output on the hi-lo is 5 or 10 or 12V depending on the white buttons, and it is constant (scope show less then +-10mV 50Hz hum)

I tried attaching 100nF – nothing changed (still counting, still same speed), tried diode too, nothing happened .. so maybe it is a counter :D .. donno what would that be useful for but ..

Anyone know what this is?

Via the forum.

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  1. It’s the ‘Destroy the World’ button. You need to operate it in conjunction with a key, which you apparently do not have. The key is available from Maplin stores, and sometimes cheaply on eBay.

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