The project uses an arduino pro mini board whose adc feature is used along with the concept of ohm s law and voltage divider circuit to develop this wattmeter.
Arduino rf power meter.
It consists of from left to right the 5v power supply the arduino nano the ad8317 module and a 2 24 character module.
Current ratio is proportional to the ratio squared.
Arduino rf power swr meter.
This sketch will readout rf power and swr from any swr bridge for example monimatch type.
In the arduino sketch i compensate for the loss in the rf tap by altering the intercept point used for the power calculation.
This sketch will readout rf power and swr from any swr bridge for example monimatch type.
Using 10 1 turns would see 1 of the rf current at the reference resistor.
Because my primary interest was for vhf uhf shf i have foreseen positions for 6m 4m 2m 70 cm 23cm and 13cm bands.
I have a 4 channel version module very similar to try out based on the ads1115.
Rf power meter default function calibration 10 and 40 dbm for each band stored in eeprom.
Code is based on sketch of mike richards g4wnc and adapted for use with an i2c oled display some display functions added.
Because my primary interest was for vhf uhf shf i have foreseen positions for 6m 4m 2m 70 cm 23cm and 13cm bands.
This figure is calculated from the power vs voltage slope of the ad8307.
Some parts do need a serial resistor some.
The intercept point is the power input required by the ad8307 to give a theoretical 0v output.
For the 2 048 volt reference you can use every reference chip you like.
Main arduino code that runs on the m5stack with graphics and buttons.
The little arduino nano uses the forward and reverse dc voltages to calculate rf power and voltage standing wave ratio.
As this monimatch type of bridge is frequency dependant the meter must be calibrated for every band.
Has some new ads1100 files to support external i2c connected adss1100 16bit adc units from m5stack.
This is a project based on arduino board which can measure the power consumption of the devices.
They work really well 0 12v inputs 15 bit useful range.
The sampling fractions usually is proportional to the square of the turns.
When we connect this wattmeter on to a device which is in operation the 16 2 lcd displays its power consumption value in watts.
