METEX M-3650B need help

[YU7C]

Hi,

After few years collecting dust, I decided to repair my old METEX M-3650B from 1993.

It seems that 7106 is broken, because it doesn't react on voltage which comes from divider. We will know a result after the chip is replaced.

Also I didn't find voltage reference, despite it exist on the schematic (ICL8069)?

Actually my main problem that i was a bit careless and during testing broke two wires between main and auxiliary boards which menage LCD for bargraph,...

Does anybody know how to right way to connect two boards?

[coromonadalix]

you have to sniff  where thoses 2 pins goes on each boards ...  the schematic is available, and find where they link

[YU7C]

Unfortunately, I didn't find schematic of auxiliary board with M-8850.

[ModemHead]

Perhaps the pictures in the following post will help.
https://www.eevblog.com/forum/testgear/how-to-take-apart-voltcraftmetex-3650b/msg585927/#msg585927

[YU7C]

Yes, that helps! Thanks.

Now waiting for 7106 chip.

[YU7C]

First, I had put UMC UM7106 which apparently should be compatible with ICL7106 but multimeter didn't work at all.

Then I found original Intersil ICL7106 and it's live again. After short calibrating process with help of 8840A it's in function.

Puzzle with UMC UM7106 remains. I found info that UM7106 has totally different function?