Old Practical Wireless Radio Circuits

Simple Two Transistor Radio

2-Transistor Reflex Receiver

Directly Coupled Transistor Radio

Here are some very old radio circuit designs that are my favourites. These circuits are usually not repeatable due to the semiconductors of that era, which are currently not readily available. However on occasion I have seen vintage old stock for sale at auction sites. If you can find the transistors and diodes, then of course it is a joy to build some of these to get an idea of how hobbyists back then built radios, and how those designs performed.