The integrated circuit used in this amplifier is uncommon today, since the project is from the 90s. The power is 24 V, and the gain of the circuit is 40dB. The input resistance is 1 M ohms.
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...