This circuit was found in 80's documentation from Analog Devices. The formulas for calculating the components as a function of frequency are given next to the diagram.
This circuit for frequencies up to a few tens of megahertz was found in the April 1978 issue of...
This is another possible version of a negative voltage generator using a 555 integrated circuit. The...
This Dimmer circuit for incandescent lamps was found in an English documentation. The input...