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My 50g has developed between 1 and 3 vertical lines in the display. When present the lines run the entire length of the display and appear at the same location (so far).

Light pressure on the display or twist on the calculator (in the right place) will make the lines go away. The shade of the line(s) is white. And remains white whether that part of the display is blank or should be showing something. It seems the problem is caused by a bad connection to the display.

I replaced the batteries even though the low battery indication was not on. No change in symptoms.

Any suggestions?

Thanks Randy
Hello,

You have 2 bad contacts between the PCB and the display.

The contact is done using a heat glued/sealed plastic flexible connector.

Most likely, this has been damaged (or the connection has weakened).

It IS possible, if you are super/very careful to fix such things, but it means opening the calculator, possibly also prying the LCD off and then re-heat glueing the connector strip, which is not an easy feat.

Usually, to do so, you place on the strip some non glue non melt plastic isolator (like anti static tape), and use the soldering iron at low temp to tranfert some heat on the connector and glue it...

I have done it once or twice, but it is hard.

Cyrille
Thank you Cyrille. I suspected a loosening and/or weakening connection.

Several years ago I had help and repaired a 39g display connection.

The 50g display repair is more than my capabilities.

I do have a prime but still use the 50g a lot. Guess I need to speed up the transition.

Thanks again. Randy
50g to Prime is not a transition it is a downgrade.
There is nothing that compares with the 50g.
Anecdote:
That problem used to plague the 48SX at the beginning of the 90s. I got one at the time with 1 missing line, and later it developed into 3 missing lines Sad. The elastomer between the display and the PCB was/is defective, it is a sandwich of rubber and some conductive but flexible compound.

I used to apply some failure locating spray to the edge of the display, and because both compounds have different coefficients of thermal expansion you can see if the problem is there, the lines become visible.
***

Looking at the photos http://s1189.photobucket.com/user/_rs1n_...sort=3&o=8

It looks like they were for the conductive foil ( Sad ), well apply so pressure between the foil and the PCB and see if the lines reappear, then, some glue may help.
(03-23-2016 06:52 PM)Tugdual Wrote: [ -> ]50g to Prime is not a transition it is a downgrade.
There is nothing that compares with the 50g.

I experienced a lot of problems updating my prime operating system. So much so tha I left a note on the hp website. To my surprise, I received a call from a real person. I took the opportunity to add my prime product update requests: Rpl enhancements, DDAYS functions, and key label color improvements. When I finally got the prime updated dday functions were included.

My 49g+ was a good machine until the keys started failing. Eventually the 50g came along and provided a good platform.

I hope hp listens to users and modifies the prime accordingly.
(03-24-2016 11:11 AM)Alejandro Paz(Germany) Wrote: [ -> ]Anecdote:
That problem used to plague the 48SX at the beginning of the 90s. I got one at the time with 1 missing line, and later it developed into 3 missing lines Sad. The elastomer between the display and the PCB was/is defective, it is a sandwich of rubber and some conductive but flexible compound.

I used to apply some failure locating spray to the edge of the display, and because both compounds have different coefficients of thermal expansion you can see if the problem is there, the lines become visible.
***

Looking at the photos http://s1189.photobucket.com/user/_rs1n_...sort=3&o=8

It looks like they were for the conductive foil ( Sad ), well apply so pressure between the foil and the PCB and see if the lines reappear, then, some glue may help.

Thanks for the info. With help I disassembled a hp39g and reseated the display connector. The photos look more complex than the 39g. The failure locator spray is a product I have not used. However, I will wait before I attempt to open the hp50g.
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