This circuit provides an audible signal when testing a TTL circuit. The circuit is from an old documentation, being fed with the 5V of the circuit under test.
This is one of the channels of an amplifier suggested by Westinghouse in 1970s documentation. The circuit...
The basis of this circuit is a double T in the feedback, which has the components calculated to...
This circuit was obtained from American documentation from the 1990s. The transformer can be a car...