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Lock circuit diagrams

A 4-Digit Keypad Controlled Switch
A 4-Digit Keypad Controlled Switch
August 3, 2010

This is a Universal version of the Four-Digit Alarm Control Keypad. I have modified the design to free up the relay contacts. This allows the circuit to operate as a general-purpose switch. I've used a... [more]

Keypad Controlled Switch No. 2
Keypad Controlled Switch No. 2
August 3, 2010

This is a simplified version of the 4-Digit Keypad Controlled Switch. I have modified the design to reduce the complexity of the circuit - and the number of components required. As a result - the... [more]

Electronic Door Release
Electronic Door Release
August 3, 2010

This circuit is designed to operate an electrical door-release mechanism - but it will have other applications. When you enter the four-digit code of your choice - the relay will energize for a preset time... [more]

Security Door electronic Key
Security Door electronic Key
August 3, 2010

It is a relatively simple circuit of electronic lock of safety with code of 7 digits. It should is given attention in the time that will be stepped the keys, that shape code and it... [more]

Electronic Security Door Key
Electronic Security Door Key
August 3, 2010

A different circuit of electronic lock very simple, one and does not need a lot of materials in order to it is manufactured. [more]

Digital Electronic Lock
Digital Electronic Lock
August 3, 2010

The digital lock shown below uses 4 common logic ICs to allow controlling a relay by entering a 4 digit number on a keypad. The first 4 outputs from the CD4017 decade counter (pins 3,2,4,7)... [more]

iButton electronic lock
iButton electronic lock
June 22, 2010

This electronic lock can be used with any type of iButtons you may already have, since the only thing needed is the internal serial number, that's different for every iButton. [more]

Electronic Locker
Electronic Locker
June 22, 2010

This circuit is an Electronic Locker. It is controlled by a switches combination (by a code). There is a switch matrix on the door of the locker. [more]

Keypad Circuit - With Parallel Code Entry
Keypad Circuit - With Parallel Code Entry
April 11, 2010

This is a universal four-digit keypad-operated switch - with a difference. Instead of entering the security code one number at a time - the four keypad buttons must be pressed simultaneously. Split the code between... [more]