In two-way radio use, AC signals were also present on the circuit pair.

If this happens an AC signal from one part of the circuit can be accidentally picked up in another part.

The two resistors (conductors) act like a capacitor thus transferring AC signals.

If an AC signal is applied across the biased electrodes, it will generate ultrasonic waves in the medium of interest.

A more versatile approach uses an AC signal applied to the electrodes.

Signaling information is encoded in AC signals which are fed into the rails of each block.

It is used for detecting the zero crossings of AC signals.

Because they are not the same sort of thing, electromagnetic waves cannot be amplified like AC signals.

In these applications, an important goal is often the recovery of information encoded (or modulated) onto the AC signal.

The devices would be set off in an emergency by altering the regular AC signal being generated and transmitted by the local power companies.