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 circuit was found in a 1978 English magazine. It is a configuration that aims to select the...
This circuit was found in Maxim's documentation from the 90's. The circuit provides 12 V x 120 mA....
This circuit can be used as a shield. Its purpose is to detect the positive front of a signal...