Electronic door lock

This electronic door lock has a remarkable conception because it uses only one active component.
How does it works ?
To put the relay in tension the 4 buttons S1 – S4 must be pressed. If anyone of the 4 butoons S5 – S8 are pushed the relay dont’s tension ( dont receives supply voltage ).
The supply voltage must be equal to the working voltage of the relay. One transistor like BD135 can commute up to 0.5A, in the same tine 2N2222 can do only 0.2A.
Enjoy this electronic door lock, its easy to build and straightforward.

Electronic door lock circuit diagram



5 Responses to “Electronic door lock”

1. chukwuma jr samuel says:

   March 26, 2009 at 11:56 am

   pls i need the diagram in my mail box.

   Reply
2. ram says:

   July 24, 2009 at 11:34 am

   orai donganakodakallara lanjadakollara ne mama parri me tatha gorrei em chestunnav bey dhed diwan dawel dadail madeil pideil lavadake bal ke lavade ne kenduku ra company musei ra piccha poo ga

   Reply
3. trinath says:

   December 7, 2010 at 4:44 pm

   please send extra description to my mail box.about what type of switches etc..

   Reply
4. paresh rathod says:

   September 19, 2011 at 10:33 am

   hey plz send me the working and some discription on it….its emergency…help me….thanks….!!!

   Reply
5. Hubert Rajakumar says:

   October 30, 2011 at 11:25 am

   I need Bank ATM’s Door circuit. I was given a chance to troubleshoot these doors. Please send it to my mail.

   Reply