This circuit from the 90s has RIAA equalization with a gain of 35 dB at 1 kHz. The circuit has an input sensitivity of 2.2 mV for an output of 100 mV.
This contact or reed switch actuation was found in a 1964 Electronic Design. The circuit can be...
This is the previous version, but with a simplification given by the use of the 7404 and 7408...
In the figure we present a circuit of a microphone signal conditioner using the SSM2167 integrated...