Sine wave frequency problem

hello
i have some part of my program that is not working well.
the idea is to sample a 2V sine wave of various frequency and record down the max and min values
by right i should get around +2 and -2 for my max and min values
however at frequencies multiple of 5(5k,10k,15k...) i get a reading of 0.0628215 for my max and -0.0628215 for my min.all other frequencies have no such problem.
i tried changing the sampling time and rate but i still get a close to 0 result for frequencies at multiples of 5.
may i know what causes the problem and how can i resolve this?

Hi
It may sound silly - but do you acquire data fast enough?
Just have a look at the Nyquist Theorem.
Thomas
Using LV8.0
Don't be afraid to rate a good answer...

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Message Edited by awais.h on 03-30-2010 11:20 PM
Message Edited by awais.h on 03-30-2010 11:21 PM
Solved!
Go to Solution.

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Thanks for the code but I'm afraid it won't work. Like you said the probability of choosing a value that is on both graphs may not happen. This is something that I would like the code to do automatically.
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Sine wave frequency problem

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