This circuit is from a Radio Electronics from October 1970. The circuit uses transistors from that era and has a low impedance output. The resistance R1 depends on the impedance of the input signal.
This circuit converts square (rectangular) signals into triangular signals with typical 16 V...
We found this circuit in a spy book from the 90s. Transistors admit equivalents and the coil can...
This circuit was obtained in a 1979 English magazine. This circuit is a treble filter that,...