1.   Frost Alarm or Cold Activated Switch

  2.   Dark Activated Switch or Porch Light Switch

  3.   Electronic Keypad by Ron J

  4.   Light Detector Circuit by Mick Devine

  5.   DC Push Button Motor Control Circuit

  6.   Push Button Switch Debouncer

  7.   Remote Doorbell Indicator

  8.   Doorbell with Counter

  9.   Digital Combination Lock

  10.  Electronic Night Light

  11.  Sound Operated Switch

  12.  Voltage Comparator Switch

  13.  DC Motor Reversing Circuit

  14.  Water Activated Relay by Marin Lukas

  15.  Triac Light Controller by Matthew Hewson

  16.  Negative Voltage Load Switch by Nicholas Choong

  17.  Voltage Controlled Switch by Miroslav Adzic

  18.  Camera Switcher by Milano de Guzman

  19.  Universal 4 Digit Keypad Operated Switch by Ron J

  20.  Keypad Operated Switch No.2 by Ron J

  21.  Electronic Door Release by Ron J

  22.  Light Controlled Relay Switch by Ron J

  23.  Schmitt Trigger

  24.  Temperature Controlled Relay Circuits by Ron J

  25.  Toggle Switch No. 1 by Ron J

  26.  Thermostat with Adjustable Hysteresis by Ron J

  27.  Toggle Switch No. 2 by Ron J

  28.  Latching Switch

  29.  AC Switch

  30.  Keypad Combination Lock

  31.  Toggle Switch No. 3 by Ron J