Faulty shift & alpha keys on hp39g


Hoping someone out there has some ideas on this one. I have an hp39g with intermittent faulty shift and alpha keys, mostly they don't work. I have tried spraying electronic contact cleaner in through the keys but this doesn't really help. Maybe it's not faulty keys but something else??

My next step is to open it up and was hoping someone who has already opened one up can point some directions my way on doing this.

Maybe this is a common problem with them, why are there so many of them for sale on the internet, ie ebay??



If it's still under warranty, I'd simply let HP exchange it for a new unit.



I should have mentioned that warranty is not an option, this is last resort stuff.



This type of housing (39G,40G,49G) is easy to open.
Just take a look at www.hpcalc.org or maybe in the forum archives here.

If you apply some pressure below the display,
and try those 'faulty' keys,
do they work then?

If yes, it's the same pcb contact problem mentionned in an hpmuseum thread a while ago (-> archives).

Another thread mentionned a company which sells new 39G's for $25. Maybe that would be an option;-)



Yes I checked and it does seem to be the pcb contact problem. I have tried searching/looking for the thread you mentioned but have had no luck, maybe someone can point me in the right direction or tell me if there was some trick in fixing this problem.



I have managed to fix the problem. To help anyone else out there who also has this problem this is what I did.

Drilled out the melted poles in the battery compartment then gently plied it open from the screen end down. Then un-twisted the pcb board tags and put a very thin piece of cardboard or thick piece of paper under the ribbon contact for the keyboard to the pcb (so as to apply more pressure), reassembled and now it works great.


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