This circuit has its frequency controlled by a 1MHz crystal. The circuit must be powered by a voltage of 5V. The capacitors must be ceramic. The generated signal is rectangular.
This 80's General Electric circuit is guarded by the noise-guard for operating current. The...
This 555-based circuit was found in the August 1976 issue of Radio Electronics magazine. The tone...
This circuit, found in 2002 documentation, triggers LEDs when a phone call is received. The LEDs...