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HP Forum Archive 19

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Hp 71b power fault
Message #1 Posted by Sean Connor on 25 Sept 2009, 8:44 a.m.

Hi all,

This is driving me NUTS. My 71b is fine on batteries but when powered from an AC adapter it keeps losing power and switching off. I thought that maybe it was a faulty wire from the AC to the recifier so I re-soldered these (The thin green and pink ones wound on the choke). It's STILL doing it. The behaviour can be aggrivated by wiggling the AC plug into the machine. What else could be loose ? Could it be that the actual pins are not being held tight enough by the adapter plug ?

I have no batteries inside themachine when I am doing this

Sean

PS I'm an electronics engineer so I don't mind swapping stuff out or soldering

      
Re: Hp 71b power fault
Message #2 Posted by Bart (UK) on 25 Sept 2009, 11:46 a.m.,
in response to message #1 by Sean Connor

Sean,

Have you checked to see if connection on the pins are good inside the unit? Also if the AC cord has been wrapped tightly, the strands inside it could be broken. Otherwise as you said it could be a loose fitting plug.

Bart


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