a 5 V from the Arduino and the transmitter. He designed the receiver side with equal care. Conceptually the circuit there is simple, consisting of the ultrasonic receiver, followed by a transistor ...

The EVE II Bluetooth Transmitter and Receiver bridges that gap with a range ... or anything else you need a wireless ...

and created and used a simple opamp circuit to boost the FPV camera video signal to the required input level for the VCO. This failed to produce any identifiable image on his video receiver goggles.