HP-65 - 1605A02841 - Weird display behavior

[teenix]

(02-11-2020 11:38 PM)albertofenini Wrote:  Thanks Tony !
What do you think of our waves ?
Do they suggest you anything we may check on the cpu ?
We have only measured Disp0 to Disp4
We didn’t have measured Rcd, should we ?
Please keep in mind we only have a two channels scope
Let us know and thanks again !

From what I can see, the wave forms appear to be ok with the exception of the first picture. If the vertical scale is the same in all pictures, it looks to be a third of the voltage of the others.

cheers

Tony