The setting of this power supply is only 0.1%. We found it in a 1969 US documentation. Transistors may be current equivalents. Note the use of symmetrical power supply.
This circuit causes an LED to flash at a frequency determined by capacitor C1. The circuit can be...
This flasher or neon signal powered by batteries was found in old documentation. The transformer must...
This circuit was obtained from an ancient American documentation, but appears elsewhere in this...