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.
In the figure we have the way to connect an LED on the output of a power source to indicate the...
The UM3562 integrated circuit is a dedicated circuit found in many toys because it generates three types...
This amplifier for public address was found in English documentation from 1967. The transistors are from...