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HP42S with bad LCD - Printable Version

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HP42S with bad LCD - husmus - 08-29-2024 04:49 PM

What Pioneer models have a compatible LCD to the HP42S in order to use as a donor? Maybe the HP17BII ? First I'll try the upside-down gentle heat suggestion. Thanks.

RE: HP42S with bad LCD - BobVA - 08-30-2024 01:34 AM

The 17BII has been discussed as a possible display donor, but a quick search didn't turn up anything definitive. These links may be of interest:

https://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv008.cgi?read=17584

https://www.hpmuseum.org/guest/brogpion.htm

RE: HP42S with bad LCD - Didier Lachieze - 08-30-2024 07:37 AM

There are two types of HP-42S: early ones with a flat display bezel and later ones with a recessed display bezel. To play safe I would use an HP-17B LCD with the first type and an HP-17BII LCD with the second type.

I have installed successfully a 17BII LCD on a 42S with the recessed bezel.

RE: HP42S with bad LCD - Geoff Quickfall - 08-30-2024 05:05 PM

I second Didier’s recommendations!

Make sure the zebra strips and the PCA and LCD contact points are CLEAN! Otherwise you will have LCD segment dropouts.

Also, when releasing the tabs to gain access, they do fatigue so you do not have unlimited attempts to get the connections on the LCD working to perfection.

Done this on the 48GX, replacing the blue with black LCD panels.


Cheers, Geoff

Didier, any more work on the PC-1300s now that you have the manual in English?

Will be presenting more on that at HHC2024.

Cheers, Geoff

RE: HP42S with bad LCD - Jwbraun - 08-30-2024 07:32 PM

Husmus

I have a LCD, zebra strips, and processor board harvested from a HP 42S flat bezel that had a faulty ON button (it was not due to the foam pad on the connector). Both are fully functional and I can provide pictures taken before they were removed to show that they worked. I am a retired EE and used all of the proper anti static equipment when handling the devices. If you are interested, send me an email or PM.

Jim

RE: HP42S with bad LCD - Didier Lachieze - 08-31-2024 04:22 PM

(08-30-2024 05:05 PM)Geoff Quickfall Wrote:  Didier, any more work on the PC-1300s now that you have the manual in English?

Will be presenting more on that at HHC2024.

Cheers, Geoff

Thanks for reminding it to me !! I’ve been quite busy with the WP43 and C47 recently, I need to take the PC-1300S out of it’s drawer and put it on my desk to remind me I should spend some time with this beautiful and exotic machine (or should I wait for your HHC2024 presentation to learn more about it?)

RE: HP42S with bad LCD - Geoff Quickfall - 08-31-2024 11:22 PM

The presentation is a fun one with some videos.

A tear down and restoration looking at the same component design that HP used in the same era.

Definitely a machine that was to be repaired and not discarded!

But the manual covers that and the programs appendix I created shows the subroutine and conditional testing the manual did not.

As well as using the ‘user’ assigned keys A, B, C, X & Y.

Anyhow, it is a beautiful machine with a gorgeous display:

[Image: IMG_4319.jpeg]


Cheers