This control for 12 V drills was found in a 90s Elektor. The components are current, and Q1 can be replaced by a TIP42 mounted on a heat radiator.
This high voltage oscillator with a neon lamp was found in a 1969 documentation. The circuit is...
This circuit is from 2005 Linear Technology documentation. The circuit applies to 12 V systems and...
In the figure we have an interesting possibility that consists of the activation of a heating...