0.3-3Ghz RF Signal Sensor

300Mhz to 3Ghz RF power to voltage converter.
You can use it to compare your transmitters, antennas or tunning your DIY antennas. 

Supply voltage: 3-15v
Freqency range: 300Mhz-3Ghz
Input Range: 0-1W (with default 12dBm attenuator)
Input Range: –28dBm to 18dB (without attenuator)
Operation Current: 0.5mA
Vout Current: 5mA Max
Vout Offset Voltage: 260mV typically 
Vout Band Width: 4Mhz (high speed output for reading uptime of digital transmitters)

If you want to use it for tunning your antenna or using on 0-18dBm mode, you must remove the input attenuator components. You can see the attenuator schematic of the circuit. You will see 3 resistor(R3,R4,R5) that marked as "101" on the SMA connector side of the board. Remove them with a soldering iron and replace the R4 with a solder drop or a piece of wire.  Your attenuator will be disabled and the sensor will direcly measure the input value between 0-18dBm
 

Documents:

• RF Sensor Characteristics (the values without attenuator, add 12dBm for default attenuator)

Important: You cant measure the real mW values with this sensor, just you can compare the transmitters. This is why we are calling it as "sensor" not a RF meter device.
Because:
1 - RF cables/wires gives different values under different frequencies. 
2 - You need a RF Calibrator device and you have to calibrate everything before every different measurement. 
3 - RF sensor not linear for every frequency, you have to calibrate the mW vs mV table before.

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