This circuit with RIAA equalization is from 1985 US documentation. The circuit has a flat response of 150 Hz to 40 kHz. The power supply must be symmetrical.
This is a circuit of an 80's American documentation and can be implemented with modern components....
This circuit converts an AC signal into a voltage of the same peak value with precision and is...
This triac circuit was found in the July 1995 Electronics Now magazine. The triac is based on the...