ARG
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Not at all, I am here to help
The rail drops on the Max IC vary from each IC, most have smaller drop, but a .2V drop shouldn't be a problem with reading accuracy. It's on the high side of the voltage drops, but nothing I would consider abnormal. If you have a couple of fresh 9V's with similar voltages you can test it out and see if the voltage difference changes readings.
You can also use an LM317 and LM337 with adjustable pots like you said to create +5.000V/-5.000V rail accuracy, but I don't think that's necessary.
I'm currently remodeling this part of the meter, using a cheap 5V to +/-15V convertor. IIRC someone has already used it in their build. Then it can be regulated to +/-12V with LM317/LM337 regulators. This way it can also be run off of USB.
I was actually going to breadboard this soon, I'll post the results when it's done.
The rail drops on the Max IC vary from each IC, most have smaller drop, but a .2V drop shouldn't be a problem with reading accuracy. It's on the high side of the voltage drops, but nothing I would consider abnormal. If you have a couple of fresh 9V's with similar voltages you can test it out and see if the voltage difference changes readings.
You can also use an LM317 and LM337 with adjustable pots like you said to create +5.000V/-5.000V rail accuracy, but I don't think that's necessary.
I'm currently remodeling this part of the meter, using a cheap 5V to +/-15V convertor. IIRC someone has already used it in their build. Then it can be regulated to +/-12V with LM317/LM337 regulators. This way it can also be run off of USB.
I was actually going to breadboard this soon, I'll post the results when it's done.
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