This high-precision circuit was found in a 1969 documentation. The components are from the period. R1 is 100 G ohms and C1 is 0.1 uF.
This traditional flasher configuration with two transistors drives 5 LEDs with a supply that must...
To operate with high input voltages using a 3-terminal voltage regulator such as the LM340-15, we...
This is the circuit of the commercial Japanese megaphone of the 60s model DM-218. The circuit uses...