This timer was found in Japanese documentation from the 1960s. The transistor can be replaced by an equivalent and the relay must be of the sensitive type with voltage according to the power supply.
This General Electric circuit was published in 1970. The LED is infrared and the voltage according...
This circuit was found in the October 1989 issue of Radio Electronics magazine. It drives an...
The transistor can be a modern equivalent and the transformer is the type of output found on an...