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HP Forum Archive 20

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restoring an HP71 (old post)
Message #1 Posted by Alberto Fenini on 20 Feb 2011, 1:11 p.m.

ciao a tutti,
someone may remember that I was trying to restore an HP71,
it was basically in nice condition, but the display had some problems.
It came out that was a bad driver, and desoldering/resoldering an SMD component it is not in my DNA.
However, I had a chance to buy a working unit in very bad cosmetic conditions
although working and of the same revision (2CDCC).
Cleaning (which was my first idea) was almost impossible,
I don't know what may have been spilled on the unit, but I was not able to remove it with whatsover solvent or soap.
As you can see from the END/LINE key, I have gone pretty far in trying to clean.
The idea was then to swap the keyboard faceplates.
I'm posting this, because I have developed a technique of soldering the keyboard that may be of interest.
Using a dremel, I have "consumed" all the plastic rivets trying not to go too deep and set free the keyboard/pcb.

Then, using a plastic glue (I don't want to make any advertising, nor I'm related to this company but I use Five star adhesive medium gap filling from the UK)
and a soft cotton tip, I have let a drop of glue fall in any hole.

The keyboard and the keyboard pcb are kept together by some paper clips
You can see how it looks when it dries here :

and then this is the final result :

Of course, while the keyboard pcb is removed you can clean and polish everything.
Hope is going to be of help for someone,
take care Alberto

Re: restoring an HP71 (old post)
Message #2 Posted by Michael Meyer on 20 Feb 2011, 3:05 p.m.,
in response to message #1 by Alberto Fenini

Beautiful! When I was in medical school, I lived on $4000 USD per year- food, clothing, shelter, etc. Buying a 71B was a huge stretch. But when I turned it on for the first time and saw the blinking cursor and realized the power I had, even in the command line, it was worth every penny. I can't quite describe that awesome feeling, and have never had that feeling again, even with all the new gadgets on the market.


Re: restoring an HP71 (old post)
Message #3 Posted by bill platt on 20 Feb 2011, 3:08 p.m.,
in response to message #2 by Michael Meyer

It is like that when you have to really really value something...

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