This receiver was found in a Japanese publication in 1967. The circuit uses germanium transistors and details of the coils are not given. Power is supplied by a 9 V battery.
In the figure we have the photo-conductive way of using a photocell to control a small motor with...
Pressing S1 the LED glows by a time interval depending on the capacitor. Time intervals in the...
This is a protection circuit in which, under excess current in the load, the SCR trips by shorting the...