This light meter circuit was found in 80's Radio Electronics. The circuit uses a milliammeter as an indicator and the sensor is a common LDR. The power supply must be symmetrical.
This new AMS device consists of a digital color sensor and proximity sensor that also incorporates an infrared...
This circuit has a gain of 10 for DC signals. The circuit is from a Radio Electronics from May...
This circuit of the 70's uses transistors of the time. The circuit can amplify signals from 10 Hz...