This low-noise, low-drift amplifier was found in a 90's EDN. It can be implemented with modern equivalent operational amplifiers. The font must be symmetrical.
Found in the 1965 Radio Shack documentation, this short-range AM circuit can be built with...
This circuit was found in a 1980s documentation. It is intended for remote vibration monitoring...
This circuit can be found on this website in similar versions. The power supply is given in...