Please Note:
Switching circuits includes a variety of circuits, some activated by light, water or voltage and others that activate on particular sensor limits. All circuits are listed alphabetically on the Circuit Index page and in date order on the update page. All contributors are listed on the credits page.

If you have problems try my help page first. Most circuits on this site use SI Notation. Due to large volumes of email, I regret that I can only answer questions about circuits on my site.

 For help or to contribute please email me
  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 Milardo 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
  32. Electronic Switch
  33. Latching Switch 2
  34. Parking Light Switch
  35. VOX Circuit By Fred Maher, Spain