Using a sensor from the time, this circuit was found in the 1992 Radio Electronics Handbook magazine. The circuit uses a pair of integrated two-digit A/D converters.
This portable transceiver circuit for the 11 meter or 27 MHz band was found in a 1991...
This circuit was found in an American 1980s documentation. It makes use of an unusual MOSFET today...
This circuit was found in an old Linear Technology documentation. The working principle can be...