Wrong Step 4 voltages

[Hegz]

Hello,

I am having an issue with the step 4, 'Check Voltages' with my DSO-150 The voltages I am reading are wrong:

Point, Tested
V+, 8.35
Av+, 5.02
V-, 0.613
Av-, 0.824
V1, 2.3
V2, 4.4
V3, 2.56
V4, 3.43

The board was provided with 9.31V and was consuming 130mA at the time of testing.

I have a 00E1 Main board, and 00F analog board. This unit was purchased from Banggood on Jan/18/2018.

Additionally the screen is displaying a solid line at the 20v mark, I had to scroll far up on the display to see it. This happens regardless of the gnd/dc/ac switch position. When the unit is powered without the analog board connected, the static is fully viewable.

Thus far I have tested resting defaults, and double checking all of my solder joints, checking resistor THT resistor & capacitor values, I haven't checked on any of the smd components.

[Hegz]

after looking at some of the other posts, it seems that potential problems are:

U5 -- ICL7660
C8, C10, C11 -- 100μ F/16V

I'll source some spares and try swapping them.

[jmonteiro]

I also have some bad Step 4 voltages with 9V input...

V+, 8.4V
AV+, 6.84V
V-, 4.06V
AV-, 5.39V
V1, 6.33V
V2, 6.33V
V3, 6.34V
V4, 5.01V

Any tips would be welcome, since I have no idea what I did wrong

Thanks,
Jorge

[Hegz]

I ended up having to contact banggood for a replacement for my issue. I'm still thinking the issue was the 7660 chip for mine.

Your voltages are quite different so it may not be the same chip that's the problem.

[grover6]

I am having same issue.