A 4-Digit Keypad Controlled Switch circuit

Posted on Feb 6, 2014

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 SPCO/SPDT relay - but you can use a multi-pole relay if you wish..

A 4-Digit Keypad Controlled Switch circuit
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