This circuit, found in 2002 documentation, triggers LEDs when a phone call is received. The LEDs will flash alternately in these conditions. Common LEDs are used in this circuit.
This circuit provides a high voltage for supplying tube or other circuits from a 12 V battery. The...
Found in an EEE from 1970, this circuit supplies a voltage of 12 V DC x 10 mA current from the...
This VCO or Voltage Controlled Oscillator was found in a Popular Electronics from 1991 but can be...