HP-65 1333S05093 restoration and display problem

[albertofenini]

Hello Everyone, Happy Christmas Season

we are in the process of restoring this unit, which is peculiar having an Italian back label,
we are wondering in how many languages these have been translated ...

So far so good, the unit has been cleaned and when the weather will improve we will spray the front with TS-80
The card reader has been rebuilt but the clutch is yet to be done
The unit reads and writes correctly so far, but we have done only a couple of read and write operations

However, the display has a faint digit partially lit in the second block of leds, it can be seen in the last picture
I'm figuring a defective block, but any suggestion is, as always, very welcome

As a tip, we have seen in a video where a Nintendo restoration was performed the use of a ice cube molder
to keep all the pieces, and we must say it's quite useful so we wanted to share the idea ...

Take care !!!

Pictures here : HP-65 1333S05093 restoration and display problem

[Roland57]

(12-29-2020 09:30 AM)albertofenini Wrote:  ...
However, the display has a faint digit partially lit in the second block of leds, it can be seen in the last picture
I'm figuring a defective block, but any suggestion is, as always, very welcome

Hello Alberto,

Such ghost segments sometimes are due to corrosion on the main PCB: this results in a shortage between the driving lines of the display. Careful inspection and cleaning will help !

Roland

[Chr Yoko]

I also have a LED segment issue on my HP97...
It seems that HP was using a line of 3 LED ships for the display.
Each chip is displaying 5 digits.

It is still possible to source HPDL 1414 chips , however they display only 4 digits each ...
And i did not found any of the 5 digits version as New Old Stock yet.

[teenix]

(12-29-2020 10:22 AM)Chr Yoko Wrote:  I also have a LED segment issue on my HP97...
It seems that HP was using a line of 3 LED ships for the display.
Each chip is displaying 5 digits.

It is still possible to source HPDL 1414 chips , however they display only 4 digits each ...
And i did not found any of the 5 digits version as New Old Stock yet.

The HP-97 has a 15 digit display module. Digits 1 and 13 only have a "g" segment because they only need to display a negative mantissa and/or exponent.

cheers

Tony