This negative ion generator was found in a 90s Popular Electronics. The autotransformer can be an automobile ignition coil.
This circuit was found in a 1987 edition of the United States' Hands-On Electronics magazine. The...
This circuit was found in a 1966’s Delco Radio documentation. Transistors are from the era, high...
Found in a 1960s RCA documentation, this circuit applies to most common triacs. The trigger device is a...