This gas sensor circuit was found in July 1976 Radio Electronics magazine. The TGS sensor was a common type at the time. Note the power supply to the circuit.
Found in American documentation from the 1970s, this circuit employs an integrated circuit from...
This circuit was obtained in the publication 101 Electronics Projects of 1979. The circuit can be...
This assembly circuit using a small motor as a generator was found in Radio Electroics magazine from...