We found this circuit in the June 1991 issue of Radio Electronics magazine. The integrated circuit is still available. The table gives the component values.
We found this circuit in a 1998 documentation. The circuit can also be used as a minutery...
This circuit supports several sets of coils and can oscillate from 1 to 44 MHz. The transistor is an old...
This circuit, obtained in an old publication, causes a second telephone bell to be played in a...