Il 24/05/2019 16:41, olaf ha scritto:
Eremita Analogico wrote:

Do you think that I can try to solve?

Of course, go ahead. :-)

I would check the quality of the internal powersupply in the next step.

Olaf



Ok, thanks.
I see that the 9V battery is directly connected to V+ and V- pins of
7106 (through power switch)

There are another 2 chips, a JRC 062D (dual op-amp, probably for Vref)
and a CD4070 that I think is for decimal point drive.

I will check these two chips...