This circuit was found in an article in Electronics Now magazine from March 1997. The transistors are general purpose, and the indicator is a 1 mA full scale analog type.
This circuit was found in a 1986 publication. However, it can still be easily assembled, as the...
In the figure we have an anti-ring circuit with 4093. The duration of the pulse is given by R1 and...
This circuit was originally indicated to generate audio signal for analog TV sound. The circuit is from...