help needed...

[shanthi13531]

guys i need to built a circuit such tat if ther is no speed it should give 5v or logic 1 signal and even for slight variation in speed the output should be logic 0.........

i built a circuit usin reed switch,frequency to voltage converter circuit, and voltage limiter but it gives voltage corresponding to reed switch how to modify this circuit to get above results

 

[Reloadron]

You really aren't providing much information. Can you please post the circuit and then in detail what you are trying to do? I am guessing a reed switch used as a speed pickup feeding a frequency to voltage converter? How many pulses per revolution of your motor? Post a circuit please.

Ron