On Jan 25, 7:07*pm, "William Sommerwerck"
wrote:
I know I'm not directly answering your question, but...

The socket and power cords are polarized. It would be extremely difficulty
to insert the plug the wrong way.


I have come across these shorted protection diodes on 2 occasions now,
both on Digital Audio Recorders powered by external wall warts. If
the wrong polarity wall wart is used, you can get the wrong polarity
12Volts to the Hard Drive. This is shorted out by the diode, which
eventually burns to a dead short protecting the drive. On both
occasions replacing the diode restored the unit to fully operational.
Good job they are there IMHO.



Gareth.