This circuit is from the Linear Applications Handbook of the National Semiconductor of 1994. Transistors are common, but the integrated circuit is not easy to obtain today.
This oscillator is enabled when a high level is applied to the control input. The operating...
This circuit uses two oscillators to produce a sound that seems the sound of a ring-bell. The...
Found in a Popular Electronics from the 9s, this circuit has output for RS-232 interfaces and current...