This Wien bridge oscillator was found in Radio Electronics from the 90s. The circuit uses the 741 which is a current component. The circuit requires a symmetrical power source.
This circuit is from a 1979 publication. The sensor consists of plates or screens that, when...
The circuit is from a Radio Electronics from August 1989. The cells used at that time did not have...
The automatic modulated siren circuit shown in the figure really produces an interesting sound...