Question about the contrast of the HP-75C/D LCD

[Namir]

Hi All,

Can one change the contrast of the LCD of an HP-75C/D? If yes, how?

Thanks!

Namir

[Sylvain Cote]

(04-01-2021 10:07 PM)Namir Wrote:  Can one change the contrast of the LCD of an HP-75C/D? If yes, how?

Hello Namir,
You have to open-up the 75 and manually adjust the LCD contrast with the potentiometer on the memory board.
Ref: PPC Computer Journal v2n5 Sept/Oct 83 Page 23, potentiometer VR at the top/right of figure 1.
Sylvain

[Namir]

:-(

That says it all! Was counting on keystroke sequence.

[Dave Britten]

(04-01-2021 10:44 PM)Sylvain Cote Wrote:  

(04-01-2021 10:07 PM)Namir Wrote:  Can one change the contrast of the LCD of an HP-75C/D? If yes, how?

Hello Namir,
You have to open-up the 75 and manually adjust the LCD contrast with the potentiometer on the memory board.
Ref: PPC Computer Journal v2n5 Sept/Oct 83 Page 23, potentiometer VR at the top/right of figure 1.
Sylvain

At least they didn't do like the Sharp PC-1211 and put a pot in there, but glue it in place so you can't adjust it.