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bz bz is offline
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Default HP Laptop power supply output plug

"N_Cook" wrote in
:

.....

not found a www ref specifically to that Compaq DC polarity.
Did just DVM the blue lead back to the mains connector and 1.3M regular
resistance back to mains ground pin, nothing showing on any other
routes.


Some of these supplies use I2C communications to 'tell the computer about
the power supply capabilities'. Without the I2C communications, the
computer may complain that the supply doesn't have sufficient capacity to
charge the computer's batteries.

--
bz 73 de N5BZ k

please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.