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Hp 71b power fault - Printable Version

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Hp 71b power fault - Sean Connor - 09-25-2009

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


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

Re: Hp 71b power fault - Bart (UK) - 09-25-2009


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.