As discussed in Part 1 of this series, as the frequency of a single or coupled tuned circuits is increased, the selectivity decreases to the point that there may be insufficient selectivity at the ...

This article is intended to introduce the beginner to the interesting and challenging art of high frequency radio design. It is also intended to entice the seasoned professional to take a deeper look ...

Fully assembled and tested in the USA by K9DP. This is the Male/Female BNC connector version. Connect the filter directly to your QRP radio without adapters! Designed to help HF radios and receivers ...

A couple of years ago one of the Hackaday Prize finalists was a project to take highschoolers through building a direct conversion radio receiver for the 40 metre amateur band. It was originated by ...