This instrument consists of a tunable resonant circuit, typically a cavity or an LC circuit, coupled to a detector. When the internal circuit resonates with the incoming radio frequency signal, the detector shows a peak output. Technicians read the physical dial position to calculate the exact frequency or wavelength of the transmitter. While older bench setups relied heavily on these manual tuners, they are still used for quick checks of microwave and laser frequencies.
Hook the output to the wavemeter and tune the cavity until you see the peak on the meter.
A wavemeter usually absorbs a small amount of power from the circuit under test, which can slightly pull the oscillator frequency if not loosely coupled.
Also heard as
- absorption wavemeter
- cavity frequency meter
Related terms
Resonance
The state in an LC circuit where capacitive and inductive reactances cancel each other out.
Resonant
Tuned to naturally oscillate at a specific frequency where energy transfer is maximized.
Frequency domain
A method of analyzing a signal by looking at its frequency components rather than its changes over time.