We found this circuit in the April 1978 issue of Radio Electronics magazine. The 2-digit circuit uses common TTL integrated circuits and must be powered by a voltage of 5 V.
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...