Hello everybody, this time I'm dealing with an HP97. It is in very good cosmetic condition, but it doesn't work ... I have already taken apart all the main components, which I will restore later (the printer group, the card reader) and I'm concentrating on the two main boards. I have already re-soldered all the points, and the only thing I have on the display is a faint (very faint) zero in different positions whan I press some of the keys like the SST, BST . I have tried with the power supply only, the battery only and the combination of both power sources. Does anybody have a good idea ? Take care,and thanks in advance for your replies, Alberto
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HP97 restore project
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Post: #5
12-05-2009, 08:29 PM
 Ciao, Alçberto; I do not have much experience with Topcats, but I have an HP97 and it had a nonworking card reader(/writer). The rest of it works fine, so I never had to deal with its internals. About the card reader, I had to adjust the many contact lids (three, IIRC), and it is not that hard. Again, be careful when using the charger. The HP97 has a different power circuit when compared to the HP67. In the HP67, the charger has three wires (unregulated Vcc, regulated Vcc and common), but the HP97 uses a two-wire AC adapter. So, it depends on batteries installed to work safely. In the 80's, I once had my first HP82143A (HP41 peripheral printer) damaged just for plugging the AC adapter and turning it ON without batteries. I did not have to wait for a 'twice in a lifetime' to remember it for good! The behavior you describe actually leads to a bad ACT (main processor), but as you have a good experience with the HP25, go ahead. And keep in mind that the Woodstocks and Topcats share the same ACT processor (except for the HP27, which uses V-MOS technology). In most cases a 'transplantation' is feasible. Success! Luiz (Brazil) ▼
Post: #6
12-09-2009, 11:07 AM
Unfortunately not much of a success till now. |