If you’re interested in learning about Very Low Frequency communications take a look at what Larry has to offer on his site. He’s put together a guide to VLF receivers that is short enough to read and clear enough to understand with rudimentary knowledge of circuits. He builds a simple receiver as a working example and a high-powered transmitter that can put out over 2600 watts. Let’s face it, radio operators were the original electronic hackers. Get back to our roots and learn the ways of the transistor.