This circuit is from an American documentation from 1975. The single junction transistors can be 2N2646 and the signal must be applied to the input of a good amplifier.
The circuit shown with the LM3914 was found in the March 1992 issue of Radio Electronics magazine. The...
This circuit was obtained from an English magazine from 1976. The circuit activates a sensitive relay...
The 8038 integrated circuit consists of a function generator with outputs of three waveforms. It...