Sometimes, it is useful to transmit a low-power radio signal to create a beacon, to send a signal carrier to a near receiver, to transmit in QRP or QRPP mode, and so on. The circuit shown here is very ...

AM radios are relatively simple devices, and building one is a good way to start exploring the world of radio communications. [GreatScott] does exactly this in the video after the break, building both ...

A new ultra-low-power method of communication at first glance seems to violate the laws of physics. It is possible to wirelessly transmit information simply by opening and closing a switch that ...

For the first time, researchers have used a laser as a radio transmitter and receiver, paving the way for towards ultra-high-speed Wi-Fi and new types of hybrid electronic-photonic devices. You've ...

With this circuit, a single transmitter and simple set of user pushbuttons can initiate one of four different outputs, two at each of two remote receivers with very different applications. The ...

For good reception, a radio must have good selectivity (selectivity is a radio's ability to separate weak stations and strong stations on the FM dial) and good sensitivity (the ability to receive weak ...

Joshua R. Smith receives funding from the National Science Foundation, the National Institutes of Health, the Department of Energy, the Department of Defense Medical Command, DARPA, Bosch, and Amazon.

This simple circuit measures the strength of a radiated signal from a transmitter. It is commonly used by model airplane builders to check whether their transmitter are really transmitting the radio ...