Simple RF Power Meter

Simple RF Power Meter

Here's a simple setup that allows them to measure the output power of their transmitter. All they need is a good multimeter with a sensitivity of 20k ohms/4 watts, which is sufficient for low-power transmitters. Many beginners have to overcome numerous problems before they can start transmitting when they first try using a QRP transmitter. A common complaint is that everything works fine, but no signal is transmitted.

The 8k resistor should be placed close to the transmitter's output terminals. Turn on the transmitter in CW mode and measure the DC voltage with a multimeter. If the voltage is V, then the output power is given by the formula Power = V^2/50.