This TTL time base for 60 Hz or 50 Hz can be used in instrumentation circuits or even with microcontrollers, serving as a precision shield. The circuit is based on 7400 NAND ports and two transistors.
We found this circuit in the February 1987 issue of Radio Electronics magazine. It is based on an...
Audio frequencies in the 300 Hz to 30 kHz range can be measured with this circuit. Transistors allow...
This circuit, suggested by Texas Instruments, is based on the integrated TL497A, designed for...