This traditional configuration with the 555 was obtained in an 80s Hands-On Electronics. The relay is of the sensitive type according to the supply voltage.
This circuit, suggested by the Linear Applications Handbook of National Semiconductor, uses a very...
Found in a 1978 publication, this circuit uses germanium transistors and drives a small 20 to 50...
This simple indicator was found in a 1980s American documentation. The circuit uses an operating system...