This circuit with a differential pair was found in the August 1974 Radio Electronics magazine. The frequency is determined by L1 and the variable capacitor.
August 2017 - Microchip's new ATtiny1617 8-bit AVR microcontrollers running at 20 MHz and 16 kB...
Found in a 1970 American publication, this circuit uses transistors of the time. These transistors...
May 2017 - Panasonic's new APS1 series of optical couplers with 3 750 V insulation and up to 50...