Dear All!
I've managed to assemble DSO138 and it seems to work but not properly.
First of all I don't see the line the curve at the display. But if I press a little bit with my finger to the top part of the board and bend it for 1 mm then I get everything OK.
Second. When CPL is switched to GND I receive 2,84V at V1 and 1,64 at V2. If I press to the board I got zeros at these two.
All the rest currencies which are available when the display is installed are OK. I've triple check the main board for undersoldering and short circuits. Everything looks fine. What would you recommend to check more?