Transmitter: Use NE555 astable mode to generate about 120KHZ oscillation pulse, then use B772 (USB 5V power supply) to amplify
Receiving end: Use 4148 to rectify the 5V tube for voltage regulation, but the voltage at the receiving end is only about 2.5V after load (change the primary, the number of turns of the secondary coil does not change significantly, and the voltage only changes about 0.1V) Why? How can the voltage of the receiving terminal be 5V?
Grayson Posted on July 24, 2020
I have seen the picture you uploaded. About 2.5 is the voltage drop between the two ends of the light-emitting diode you connect to the load. Connect a resistor in series with the anode of the load light-emitting diode. A few K ohms are fine, and the load will have a voltage of 5V.
Mohammed Posted on July 24, 2020
Are there transformer parameters? See how much the transistor current is, you can reduce the number of coil turns adjustment.
Skylar Posted on July 24, 2020
The output current is small, which is related to the coil coupling distance.