Resurrected 2 HP 48

[gwh]

I have to toot my own horn somewhere to cheer me up and it'll be here.

I am quite happy to have successfully brought back to life 2 HP 48 from my graveyard, yesterday a 48GX that had a faulty keyboard when I bought it.

I carefully opened it some months ago and procrastinated ever since. Then last evening I had nothing left to buy before I had to actually do it so I did it.

Process:
- opened it (using this method: https://www.hpcalc.org/details/4701 )
- cleaned connectors with alcohol (Isopropanol 99.9%)
- replaced screen with the black one from a cannibalized 40g
- put silver connective paint on the keyboard connectors on the motherboard (with a fine paintbrush)
- replaced keyboard contact foam with a double layer of double face 1.5mm thick adhesive foam

And to my own surprise it worked (almost) perfectly! ("Almost" because I can't seem to close back the top of the case. I haven't tried to slot in a card but otherwise it's fine)

So I just did it again with a 48SX this time, not replacing the screen, just fixing the keyboard. Another success!

I have renewed hope for the 1 48GX, 2 48SX, and 2 48G left to go (but 1 48G is a bit beyond hope.)

[BillBee]

Good Job! I does feel great to bring an HP back to usefulness.

Sometimes the plastic stud top will mushroom a bit and cannot fit back into its hole. I have trimmed the edges a bit with a side cutter allowing it to pop back in.

-Bill

[gwh]

(06-05-2023 05:43 PM)BillBee Wrote:  Good Job! I does feel great to bring an HP back to usefulness.

Sometimes the plastic stud top will mushroom a bit and cannot fit back into its hole. I have trimmed the edges a bit with a side cutter allowing it to pop back in.

-Bill

Thanks, I'll try that for the next ones.

[EugeneNine]

Thats why I prefer to take the metal overlay off the front so I can cut the heads off the studs cleanly.

[gwh]

(06-05-2023 06:08 PM)gwh Wrote:  

(06-05-2023 05:43 PM)BillBee Wrote:  Good Job! I does feel great to bring an HP back to usefulness.

Sometimes the plastic stud top will mushroom a bit and cannot fit back into its hole. I have trimmed the edges a bit with a side cutter allowing it to pop back in.

-Bill

Thanks, I'll try that for the next ones.

So I went ahead and reopened both the GX and SX, trimmed the studs' "mushrooms" and now I can close both properly. Even happier with the result.

(06-05-2023 07:28 PM)EugeneNine Wrote:  Thats why I prefer to take the metal overlay off the front so I can cut the heads off the studs cleanly.

I may experiment with your technique on one, I'll see. Also while looking for your post describing your technique I saw your question about the replacement of the keyboard foam: I use a double layer of this: https://www.amazon.fr/dp/B0BJ2FBN1V and I keep the plastic on the top (so as not to glue the keyboard connector of the foam)

[EugeneNine]

I found a single sided foam tape
https://www.amazon.com/gp/product/B071G4...UTF8&psc=1

[johnb]

(06-05-2023 05:08 PM)gwh Wrote:  So I just did it again with a 48SX this time, not replacing the screen, just fixing the keyboard. Another success!

I have renewed hope for the 1 48GX, 2 48SX, and 2 48G left to go (but 1 48G is a bit beyond hope.)

Hey, congratulations!

It does feel awesome to rescue one of these historical pieces from the jaws of the scrapheap, doesn't it?

So, you have 3 48sx'es?

Any chance that when you've got 2 or more of them resurrected, you might be willing to sell one? My 48gx needs an older brother, you see.

[gwh]

(06-11-2023 06:13 AM)johnb Wrote:  

(06-05-2023 05:08 PM)gwh Wrote:  So I just did it again with a 48SX this time, not replacing the screen, just fixing the keyboard. Another success!

I have renewed hope for the 1 48GX, 2 48SX, and 2 48G left to go (but 1 48G is a bit beyond hope.)

Hey, congratulations!

It does feel awesome to rescue one of these historical pieces from the jaws of the scrapheap, doesn't it?

So, you have 3 48sx'es?

Any chance that when you've got 2 or more of them resurrected, you might be willing to sell one? My 48gx needs an older brother, you see.

It does feel great!

I put the SX I fixed on ebay [ https://www.ebay.fr/itm/266293004266 ] (someone else's is also available https://www.ebay.fr/itm/325682375586 )

Of the other 2 I haven't met success yet. ( https://photos.app.goo.gl/2AR74k7tDPtCMxHi6 )

- the one on the left (3316S00346) I'm afraid is too far gone for me to save it, half of the keyboard connectors have been completely eaten away, even the screen's connectors aren't looking perfect. I did the same treatment, changed the screen with one from a hopeless 48G, applied conductive paint but it still doesn't turn on. The mainboard of this one looks more like a GX one.

- the one on the right, (3014A01382, made in USA) even though I failed I still hope I can save it, maybe. Nothing looks wrong but it still doesn't boot. The hourglass indicator turns on sometimes but that's all. If I can't save it I want to make it into "art", I love the look of the original SX mainboard so I'll put it in a frame along its case which looks good too.

- I also worked on the 48G @Tugdual kindly sent me but same story, haven't met success yet.

I found it quite interesting how the 3 SX have 3 different boards. Even the 3014A01382 (made in USA) and the fixed 3152S07335 (Singapore) are different revisions of the original board. I regret not taking pictures of the 3152S07335 board but I don't want to open it again now.