This circuit was featured in the March 1972 issue of Radio Electronics magazine. It adds automatic gain control to turntables by acting directly on the cartridge signal.
Found in a 1969’s Electronic Design, this circuit operates in a narrow range of voltages....
This power stage with two counterphase transistors and coupling transformers was shown in Radio...
Found in old documentation, this circuit uses special discharge lamps (neon) of the time. The...