I have also been toying about building a "black Box" to monitor things. Besides the fuel level monitor, outside temp, data from EMC2 and such. I can program it but building the components is the challenging stuff and that is why it interests me. As i feed the airplane voltage into my application, I divide the current by 1/3 so that I can feed my microchip ADC. In my prototype, I have been using 1M resistors to do the division. Does it matter on the size? My thinking is, since I only want to voltage, the higher the better.
Bob K
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