This circuit was found in a PE Hobbyst Handbook of 1989. It uses a black light fluorescent of the time. Small fluorescent black light from 1 to 4 W can be used.
This amplifier was found in a 1957 Rayrtheon documentation. The circuit can be fitted with a BC558...
This circuit was obtained from the May 1971 issue of Radio Electronics magazine and is intended for...
Although it is a common configuration today, this circuit was taken from an old publication. The...