In article .com,
wrote:
We disagree. Regular switches will carry current regardless of the
polarity. Most certainly the switch (if any installed) is fine and it's
something further inside the power circuit. Reversing of polarity on
the power supply WILL almost certainly fry the inside of a device, so
one must be careful when connecting the PS (I know as well, I have done
the same in my day). As for buying a new one, that's great if you can,
but from what I've seen, this model retails for a few hundred dollars.
Good luck

It only needs one diode to protect against wrong connection, and many
things that take disposable batteries are fitted with protection since
it's all too easy to fit those incorrectly. Under those circumstances it
would be likely that diode would protect from wrong connection of the PS
too.

Many of these devices use a SMPS to give a constant supply regardless of
battery voltage etc, and that too *should* incorporate reversal protection.

But then 'they' do tend to save on tiny costs wherever possible...

--
*Beauty is in the eye of the beer holder...

Dave Plowman London SW
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