After I fixed one problem with the help of the group members, I have another puzzle.
At the pin 12 of U305, I am getting -8~+8. I removed the chip. Now I am getting -10V. Data sheet of the LM339N says it is ground pin and Fluke's schematic doesn't show the pin number 12. So I think they omit the pin 12 from the schematic for the obvious reason.
I enclosed the schematic in pdf. Please take a look at. I read the hand writing of U305 in the schematic as "LM339"
Thank you in advance for whatever the suggestion is.
At the pin 12 of U305, I am getting -8~+8. I removed the chip. Now I am getting -10V. Data sheet of the LM339N says it is ground pin and Fluke's schematic doesn't show the pin number 12. So I think they omit the pin 12 from the schematic for the obvious reason.
I enclosed the schematic in pdf. Please take a look at. I read the hand writing of U305 in the schematic as "LM339"
Thank you in advance for whatever the suggestion is.
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