Design Reference Compendeum

While putting together ideas for homebrew radios, I often find myself trying to pull together ideas from different design families. How do different designers, profession or homebrew, handle, say, the link between an LM386 and NE602, or T/R switching, or IF strips between two mixers, and so on…

Below is a list of links and resources for some specific design areas of personal interest. It’s not an exhaustive list, and many links are duplicated where a design or resource applies to multiple categories.


  • Lorem
  • Ipsum

Audio Pre-Amps

NE602/LM386 Direct Conversion Receivers

NE602 Superhets

Double Sideband Transceivers

Twin Crystal Filter Transceivers

Phasing SSB Transceivers

  • VK3YE SSB trx – LM386 shared as mic amp and receiver audio amp, diode ring mixer, simple phasing arrangements.

IF Amplifiers

T/R Switching Ideas

  • QRPKits Easy TR Switch – RF-Sensing using BS170 and 2n3906 to control DPDT relay
  • 7N3WVM – Multiple ideas, and a compilation of others
  • KN-Q7 – Simple trannsistor-based power switching

RF Power Amplifiers

Magnetic Loop Antennas

Other Interesting Ideas (aka Unsorted)

Other Link Collections: