I have published the Arduino+AD8318 milliwatt meter code on github. I have changed the slope (can be re-computed with calibration), intercept points and the table with correction factors.
Note that I use LiquidCrystal_PCF8574 library for driving the I2C 16x2 display to avoid incompatibilities between various LiquidCrystal_I2C versions (same name, different API!).
The hardware circuit around Arduino is the same of PA0RWE's design.
I still get too high power readings with about 5 mW UHF at AD8318 input and I suspect it's because the error is very high, at least according to the datasheet graph (900 MHz reference).
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| Typ. AD8318 response at 900 MHz. |
