Loop powered devices are modules and computer boards which are powered by the system they serve.

IC phase-locked loops (PLL) are closed-loop frequency controls that are based on the phase difference between the input signal and the output signal of a controlled oscillator

Power operational amplifiers (POA) are used to increase the power of low-level signals in applications that drive low impedances or reactive loads.

Fiber optic power meters are instruments that measure the average power of a continuous light beam.

Signal isolators must be used when connecting grounded signal sources to grounded signal followers.

Frequency-to-current converters accept a frequency (an AC signal) and produce an output current whose value is a function of the input frequency.

Antennas are structures or devices used to collect or radiate electromagnetic waves.