With distortion of less than 1 dB from 10 Hz to 20 kHz this circuit was found in the December 1972 issue of Radio Electronics magazine. The amplifier is a type that preceded the 741, the 709.
This is a multi-component tester with visual indication by LED and polarity selection in the test....
This circuit is from a 1978 operational amplifier manual. The power supply must be symmetrical, and the...
This circuit is stabilized by a thermistor or NTC with a resistance between 2 and 5k. The signal is...