This rectangular signal generator was found in an Electronics World of 1966. The transistors are from that time and modern equivalents can be tested.
The traditional circuit was taken from a French magazine Radio Plans that no longer exists but can...
This monostable circuit, from a 1977 Radio Shack documentation, uses a 7400. The time is given by the...
The circuit shown in the figure activates a small indicator lamp that will start to flash when the...