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.
The indicated circuit performs a slow charge of 12 V batteries maintaining a constant current of...
Found in a 73 magazine from the 1980s, this circuit generates signals from 3.2 to 22 MHz. FETs can be...
In the figure we have a three-phase AC motor control for voltages up to 600 V or 1200 V depending on...