restoring an HP71 (old post)


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


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.



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

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