Last month I wrote some about making a notch filter for the AM band. However, before you have any signals to notch out, you must first, of course, have some signal to begin with. Let’s talk a little ...

AM reception can be very difficult because of the inherent succeptibility AM has to electrical noise and other sources of interference. The built-in antenna in most receivers – a coil and a ferrite ...

Using digital techniques has caused a resurgence of interest in VLF — very low frequency — radio. Thanks to software-defined radio, you no longer need huge coils. However, you still need a suitable ...