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Tugdual · 12-29-2022, 08:13 AM

Looks like my old Hp48 is now completely dead.
It used to power up with some difficulties when I acquired it a couple of years ago but now it won't turn on. I finally decided to open it without too much damage on the casing though it won't close very firmly. I even removed the main board to clean contacts for screen and keyboard but I juts can't get it to work.
As it is totally dead, I'm not sure I want to keep it now. I have a 50C that works well and faster.
I also have the books in FR. I'm on the verge of dumping the whole thing.

What should I do?

Kiwi · 12-29-2022, 10:05 AM

If it's still possible, did you try to press slightly under the LCD screen, just above and between the B and C keys ?
Even if you cleaned the contacts, it could be that the foam under the keyboard ribbon cable doesn't make enough pressure for the ON-key trace to work.

Tugdual · 12-29-2022, 02:58 PM

Hi Kiwi, I had tried to press On and between B & C. Without success.
I had already noticed the use of foam in the battery compartment instead of springs. Quite a questionable design choice.
Anyway the machine is now totally inert and I will probably throw it away if there is no good use of the wreck as spare parts. I guess that was my initial intention when I posted here.

Chr Yoko · 12-29-2022, 03:55 PM

Seems like you need to look at the used market to get a newer one.
Should not be a big deal as there are still a plenty available.

franz.b · 12-29-2022, 07:41 PM

(12-29-2022 02:58 PM)Tugdual Wrote: Hi Kiwi, I had tried to press On and between B & C. Without success.
I had already noticed the use of foam in the battery compartment instead of springs. Quite a questionable design choice.
Anyway the machine is now totally inert and I will probably throw it away if there is no good use of the wreck as spare parts. I guess that was my initial intention when I posted here.

don't throw it in the trash! it will be very useful to someone else who wants to repair another 48. sell it or give it to someone who puts it to good use!

gwh · (This post was last modified: 12-29-2022 08:47 PM by gwh.)

I'd say sell it as is, for parts. Or give it to me, I'm in France I'll pay for shipping Wink

Kiwi · 12-30-2022, 09:35 AM

Well, I don't think there are a lot of options left then. As some of the other contributors mentioned, sell it as defective or give it away. Maybe you can split the manuals from the rest.

Tugdual · 12-31-2022, 01:08 PM

(12-29-2022 08:45 PM)gwh Wrote: I'd say sell it as is, for parts. Or give it to me, I'm in France I'll pay for shipping

Please PM me your address and I will send it to you. Manuals are also in French so you might be interested despite the heavier weight. Happy new year.

gwh · (This post was last modified: 01-01-2023 10:35 AM by gwh.)

(12-31-2022 01:08 PM)Tugdual Wrote:
(12-29-2022 08:45 PM)gwh Wrote: I'd say sell it as is, for parts. Or give it to me, I'm in France I'll pay for shipping
Please PM me your address and I will send it to you. Manuals are also in French so you might be interested despite the heavier weight. Happy new year.

Sent (an email, can't seem to do PM), merci et bonne année 2023 à tous (thanks and may 2023 be kind to you all)

Tugdual · 01-02-2023, 01:11 PM

(01-01-2023 09:45 AM)gwh Wrote:
(12-31-2022 01:08 PM)Tugdual Wrote: Please PM me your address and I will send it to you. Manuals are also in French so you might be interested despite the heavier weight. Happy new year.

Sent (an email, can't seem to do PM), merci et bonne année 2023 à tous (thanks and may 2023 be kind to you all)

Just found it in my Spam box! Gimme a few days and I’ll work on it.

gwh · 01-10-2023, 08:21 PM

Update: I received it, thank you very much!
I tinkered with it but haven't been able to revive it (yet.)

I'll try again, I at least hope to get some point so I can hope to fix the 2 other 48 in need of surgery that I only just opened for now.

a GX with a faulty keyboard (a row and a column aren't responding) but otherwise working.
a SX (Made in USA) that only showed an indicator once and now nothing (like this G)

I do find it a bit disappointing to see how "repairability" seem to never have been a concern during conception… Oh well.

Didier Lachieze · 01-10-2023, 08:58 PM

(01-10-2023 08:21 PM)gwh Wrote: I do find it a bit disappointing to see how "repairability" seem to never have been a concern during conception… Oh well.

The priority for the HP 48 design was to leverage the Pioneers assembly processes to reduce costs and design time as explained in this HP Journal article from June 1991 describing the detailed assembly process of the 48SX:

Quote: When work started on the HP 48SX, design engineers were given the goal to use as many of the design concepts from a 1-and-2-line display family of calculators (HP 10, 14, 17, 20, 21, 22, 27, 32, and 42) as possible. This was done to reduce the amount of new development needed and to allow the new machine to be built on the same production line as its simpler cousins. The 1-and-2-line family set new standards in HP for calculator manufacturing efficiency and we wanted to extend this efficiency to the HP 48SX. Using proven designs shortened the typical design/build/test/redesign cycle, shortening the whole design process. It also meant that there were no new manufacturing processes to develop. This reduced the cost and delivery time for the assembly tooling.