This circuit monitors extra-low frequency (ELF) fields. We found it in an American documentation from the 90s.
This circuit has a frequency range of 30 Hz to 100 kHz with an output signal of 1 Vrms. We found...
This circuit is suggested by the Optoelectronics Sourcebook by Texas Instruments when AC signals...
This sequential relay actuation system circuit for traffic lights was found in Electronics Now...