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Sharp PC 1211 display change -- problem overnight -- suggestions? - Printable Version

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Sharp PC 1211 display change -- problem overnight -- suggestions? - Gene Wright - 05-14-2012

Yesterday, this was working great! Turned it on today and this is what is shown. Middle 8 characters of the 24 character display are gunked up. Any suggestions? It was not hit or abused from yesterday. :-)


Edited: 14 May 2012, 11:04 a.m.


Re: Sharp PC 1211 Display change -- overnight - Valentin Albillo - 05-14-2012

Hi, Gene:

Sorry for your loss, I don't think that's repairable at all though it will still work as always, just much less readable.

Did you place it somewhere at high ambient temperature (a car under the sun, etc) ?

Antique yellow LCD displays eventually suffer this fate, I've seen three SHARP handhelds affected this way. Aware of this problem, SHARP released the same identical machine with a better grey LCD, the SHAR PC-1212, which is less prone to suffer from this.

Matter of fact one of my yellow-LCD SHARP PC-1211 is in this sorry state while all of my otherwise identical grey-LCD SHARP PC-1212 units are just fine.

Best regards from V.





Re: Sharp PC 1211 Display change -- overnight - Gene Wright - 05-14-2012

Sadly, no, I did nothing strange to it at all.

Yesterday, it was working fine. Put it in its protective sleeve and on the table overnight. No heat sources, no abuse. :-)

Today, this is what it shows when it turns on. Oh well. It wasn't expensive, but sad nonetheless.


Re: Sharp PC 1211 Display change -- overnight - Valentin Albillo - 05-14-2012

Quote:
Sadly, no, I did nothing strange to it at all.

Yesterday, it was working fine. Put it in its protective sleeve and on the table overnight. No heat sources, no abuse. :-)

Today, this is what it shows when it turns on. Oh well. It wasn't expensive, but sad nonetheless.


The Lord giveth and the Lord hath taken away ...

My sincere condolences.

Best regards from V.




Re: Sharp PC 1211 Display change -- overnight - fhub - 05-14-2012

Quote:
The Lord giveth and the Lord hath taken away ...

Are you sure?

So far the Lord hasn't given me any of my calculators - I had to buy all of them myself. ;-)

Maybe the problem is that I don't have the 'right' Lord!? :-)

Franz


Re: Sharp PC 1211 Display change -- overnight - Valentin Albillo - 05-14-2012

Quote:
Maybe the problem is that I don't have the 'right' Lord!? :-)

Among other things ...

V.




Re: Sharp PC 1211 Display change -- overnight - Eric Smith - 05-14-2012

I thought it was "Moore's Law giveth, and Microsoft taketh away". Though I don't think this particular problem can be blamed on Microsoft.


Re: Sharp PC 1211 Display change -- overnight - Trent Moseley - 05-14-2012

Valentin

I have a SHARP PC-1500A. Is that a similar machine?

Trent Moseley


Re: Sharp PC 1211 Display change -- overnight - Valentin Albillo - 05-14-2012

Quote:
I have a SHARP PC-1500A. Is that a similar machine?

No, not at all. Much bigger, much more solidly built, reliable grey LCD display, much better BASIC dialect, better CPU, the works.

A very nice early model, congratulations. I have three or four, mostly mint, as well as a NIB SHARP PC-1600 which is the wonder of them all.

Regards from V.




Re: Sharp PC 1211 Display change -- overnight - Bill (Smithville, NJ) - 05-14-2012

Hi Valentin,


Quote:
as well as a NIB SHARP PC-1600 which is the wonder of them all.

I second that!

I have several that I play with a lot. The ability to have 80k of memory along with 32K - 256K memory ram drives make it a very powerful system. I mostly like it for the Z80 processor. My first computer was a Z80, so doing machine code on a handheld is a lot of fun. I'm fortunate that I have a lot of memory modules from 16K to 256K, so I can save/load files with ease.

Now if I could just find a working CE-1600P printer/plotter with a working floppy drive - then I could make use of those two boxes of disks I picked up seveal years ago.

Bill




Re: Sharp PC 1211 Display change -- overnight - Valentin Albillo - 05-14-2012

Quote:
I mostly like it for the Z80 processor.

Yep. As you probably already know it's got a second CPU for backward compatibility with the 1500, 1500A models.

Quote:
My first computer was a Z80, so doing machine code on a handheld is a lot of fun.



I concur. I bought a good Z80 Assembler course just before joining the military and thoroughly assimilated it while there. I fondly remember creating a whole video game for the Sinclair ZX81 entirely in Z80 machine code from scratch, converting the mnemonics to hexadecimal codes and computing the addresses and jump offsets entirely by hand as I had no compiler, assembler, or even the machine proper to begin with.

Upon entering it into the ZX81 it ran perfectly, I just had to fine-tune some delay loops to make it humanly playable as it ran so incredibly fast. :D

Best regards from V.




Re: Sharp PC 1211 Display change -- overnight - LHH - 05-14-2012

I'm not sure how much trouble it's worth to you but you might disassemble and see if the problem is related to the commonly-used "zebra" connectors. These are used to connect the PCB traces to the metal deposition on the LCD itself. Usually they are made of some rubber compond and can shrink/harden with age. You can probably find something similar online though you may need a good straightedge and a sharp razor to cut it to the size you need. Also check the PCB connector area for any corrosion or oxidation. Sometimes it's the metalization on the LCD too. I have repaired those using some silver paint (sparingly!). I once bought a Fluke 8050A on eBay cheap because the display was inoperative. The LCD glass was actually chipped in the connector area but I was able to restore it with the silver paint technique and it's been working fine for years now.

LHH


Re: Sharp PC 1211 display change -- problem overnight -- suggestions? - Bart (UK) - 05-16-2012

It seems those blocks are permanently turned on, not a "leaking" display (well, not in the usual way). Have you tried to reset it or remove the batteries for a few days?