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.
With the coded activation of the relays, it is possible to control which of the 16 outputs...
The integrated circuit used in this application is not very common. Transistors and resistors...
This simple circuit makes use of neon lamps to indicate the voltage of a power grid. The lamps are...