We found this circuit in the July 1969 Radio Electronics magazine. The circuit uses a coupler made with a lamp and an LDR. The power of the lamp determines the types of diodes.
We found this shield circuit in a 1991 technical documentation. The phototransistor can be...
January 2017 - Texas Instruments is making available through Mouser Electronics the new Buck...
The figure shows how to obtain a locking relay for an alarm circuit with sensors in series and in...