This different circuit was patented and described in the Radio Electronics magazine of March 1958. In that section it used to present different configurations that received patents.
This circuit appeared in a noverber 1962s Practical Electronics. The magazine is no more, but the...
This circuit is from an American 80's documentation. The integrated circuit is from the time and...
Other series amplifiers such as the MC3301, MC3401 and LM2900 can be used on this circuit. We...