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Question about Bleeding HP-71B LCD - Printable Version

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Question about Bleeding HP-71B LCD - Namir - 03-20-2016 12:42 AM

I have an HP-71B and noticed the lower left side has an LCD bleed (dark area). It does not interfere with the LCD display. For those who have experienced LCD bleeds, do these bleed progress at all, progress slowly, progress quickly, or it varies?



RE: Question about Bleeding HP-71B LCD - Geoff Quickfall - 03-20-2016 01:29 AM

Hello Namir!

Hope all is well.

The bleed is a result of the LCD panel delaminating. Probably due to the adhesive joking the upper and lower surface degrading. Sadly It will progress but in a stable environment (no shocks or large temperature changes) it may last for years.

To access the LCD panel a set of heat stakes must be de-capped. The LCD panel is kept in place by a series of tabs. So the panel can easily be replaced, but the heat stakes are problematic.

Cheers and see you in the fall, Geoff

RE: Question about Bleeding HP-71B LCD - Paul Berger (Canada) - 03-20-2016 03:32 AM

I have a parts 71B that the LCD is intact on, I do not know for sure it is functional, but the 71B seems to have died from an electronic failure, and I think when you swap the display, you would be just swapping the glass.

RE: Question about Bleeding HP-71B LCD - Brian D - 03-20-2016 07:24 PM

For many years I kept a 15C in the truck to compute gas mileage. During this time it developed a small spot in the corner of the LCD. Since then I got smart and now keep it inside, replacing it with a $10 calculator.

The spot has not changed at all, and it's been a decade or more.