This is an experimental generator based on the IRF510 transistor for short waves. Experimental because the frequency of this generator is unstable. I received the signal of this generator at a distance of 2500 kilometers on a websdr receiver.Generator frequency approximately 3.2-3.5 MHz.
Coil L1 contains 27 turns and L2 7 turns wound on top of L1. The windings were wound on the body of an 18650 battery. The diameter of the wire is 0.6 mm. Coil L3 is 16 mm in diameter and contains 10 turns of wire with a diameter of approximately 0.6 mm
How to set up a generator. First, connect a 10 W, 12 Volt incandescent lamp to the drain of the transistor through a 10n capacitor. The lamp should shine. This indicates that the high-frequency signal passes through the capacitor and the generator is working. If the generator does not start, swap the terminals of the L1 windings -L2
Then connect a 50 Ohm cable 0.5 meters long to the filter output and connect a 50 Ohm resistor to the cable load. The resistor must be non-inductive.
With a power supply of approximately 17 Volts, the resistor will produce a sine wave with a swing of 40 Volts, which corresponds to a power of 4 Watts.
40V/2=20V (AMPLITUDE)
20v/1.4=14.28
14.28*14.28/50=4 watt
Connect the antenna to the output of the generator. I connected the Fuchs antenna about which I already wrote about how to make it. Bring a neon lamp to the connection to the antenna wire and the lamp should shine in your hands, which indicates good high-frequency voltage.
I waited until night and turned on the websdr receiver, which is located at a distance of 2500 kilometers from my generator. My antenna is a Fuchs antenna, which I already talked about how to make it. I received the generator signal at a frequency of approximately 3.18 MHz, this can be seen in the form of a strip on the screen
