This detector uses an unusual sensor today. The circuit is from an 80s documentation. Its sensitivity is 10 ppm. The transformer has two secondary voltages.
This circuit was found in an Argentine publication from 1973. It uses a common AM coil (50 + 50...
To obtain rectangular 1 kHz signals, we can have a simpler configuration, with a single amplifier, as...
E) Using a CA3130 this preamp has excellent gain. The power supply does not have to be...