need help in circuit design

[abhay kulkarni]

Hi
I want to make a circuit to detect a missing pulse and to drive a relay when a missing pulse is detected and the relay should be de-energized when pulse resumes again.
pl. help.
Thanks

 

[jpanhalt]

A missing pulse detector is a standard 555 circuit. Have you searched on that?

What is the frequency of the signal for which you want to detect the missing pulse?

John

 

[abhay kulkarni]

Yes I have used missing pulse detector using 555,and it works on missing pulse means the out put changes when pulse is missed. I want the out put to become normal when pulse resumes again and it should work again and again.
Thanks.

 

[jpanhalt]

It may just be a simple matter of adding an inverter (a single transistor). Please draw what you want.

John