18 April 2022

Milliwatt meter with AD8318 Arduino code

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). 

Typ. AD8318 response at 900 MHz.
Typ. AD8318 response at 900 MHz.