This 13.6 V power supply with 8 A output was suggested by Texas Instruments in the documentation of the 90s. Power transistors must be equipped with good heat sinks.
This efficient filter against EMI has several coils, being L1 and L2 formed by 100 turns of wire...
This optical sensor circuit for a robot was found in the March 1986 issue of Radio Electronics magazine....
This circuit can provide both positive and negative voltage outputs from 2 to 12 V with current up to...