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HP Forum Archive 20

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Frozen HP-71B
Message #1 Posted by aj04062 on 9 Aug 2011, 8:12 p.m.

I recently pulled my HP-71B out of it's box to experiment with again. I had left some brand new alkalines in it. I know it was working when I put it away. When I went to turn on it came on but is now frozen. I don't know if the characters are important (looks like the last values that we put in) but they are: 22222220**-*7 cursor then a strange character

I have tried several discharging approaches with no success. Does anyone have a foolproof way to discharge the cap? It sure seems like this is the issue.

I've tried shorting the contacts, repeated ON button pressing and letting it sit 24hrs.

I also tried most ideas on this link old thread

Edited: 9 Aug 2011, 8:35 p.m.

      
Re: Frozen HP-71B
Message #2 Posted by Mike on 9 Aug 2011, 9:04 p.m.,
in response to message #1 by aj04062

Have you just tried resetting the 71B? ON / (Init1).

Edited: 9 Aug 2011, 9:07 p.m.

            
Re: Frozen HP-71B
Message #3 Posted by aj04062 on 9 Aug 2011, 10:46 p.m.,
in response to message #2 by Mike

Yes, It will not get that far. It is totally frozen on the characters I described.

Edited: 9 Aug 2011, 10:47 p.m.

      
Re: Frozen HP-71B
Message #4 Posted by Vladan Dugaric on 10 Aug 2011, 4:38 a.m.,
in response to message #1 by aj04062

To discharge, take the batteries out, then open the card reader port and short pins 1 and 11 (or all of them) using something conductive. This only takes a second or so, no need to keep shorted for a long time. Then put the batteries back in and the 71 should be completely reset.

Vladan

            
Re: Frozen HP-71B
Message #5 Posted by aj04062 on 10 Aug 2011, 7:57 p.m.,
in response to message #4 by Vladan Dugaric

Shorted Pins 1 & 11 and installed new batteries. Nothing but a blank screen. I then cleaned the battery contacts as I discovered one spring set was corroded and wasn't passing current.

IT's ALIVE!

THANKS ALL!


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