Stereo preamplifier TDA3410 (CB21937E)

Taken from the 1982 SGS manual on integrated circuits, this preamplifier was used in commercial equipment at the time.

LED VU KA2283 (CB25369E)
This mono circuit for 10 LEDs was found in the January 1991 Radio Electronics magazine. It is...
1 600 meter Line Receiver (CB1554E )
In the figure we have a line receiver circuit (twisted pair) with the possibility of...
Neon Audio Oscillator (CB11535E)
This circuit was originally designed for the practice of Morse code, something common in 1966, the year...