This circuit with two operating modes was found in the September 1989 issue of Radio Electronics magazine. Other operational amplifiers can be used. The power supply must be dual.
We found this different configuration that uses a fluorescent lamp as a negative resistance device...
This modern regenerative receiver was featured in the March 1994 issue of Electronics Now...
This circuit is from a 1980s Motorola documentation. The circuit makes use of old components that can in...