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 simple circuit, which requires a low current (50mA) relay for 5 to 12V power supplies, was...
We found this circuit in a publication from the 1970s, but it can still be assembled today by...
Found in a Motorola documentation from the 70s, this circuit makes use of transistors of the time....