This General Electric circuit produces pulses of light only when light stops shining on the sensor. Equivalent SCRs can be used and the trigger adjustment is done in a trimpot. The maximum load is 40W.
This circuit, from an old Argentine publication, makes it possible to use a 1 mA full-scale...
This conventional series reducer circuit reduces the voltage of a 12 V battery to the selected value...
With the used coils and the power transistor this circuit amplifies the 5 W of a 11-meter...