FRF Problem about amplitudes of two sine signals

Hi everyone,
I'm carrying out a FRF operation between two acquised signals, so I decided to simulate it simply first.I created two dummy sine signals with 50 Hz frequency value and "1" amplitude level for both.And I divide the second signal with a integer and took the FRF function between them, as below.
as expected for all frequencies, the result is 0,5 which comes from the ratio of sig2 to sig1.
But, when I changed the integer value to a float, 1,3 for example, it results nonsense;
Why these two processes do not match?
Thanks,
Ozgur

Deborah, it happens every time as Jeff indicated. Thanks anyway.
Jeff, am I understanding right, you're saying that the graph shows the sum of the errors that caused by the uncertainity? And there is another thing, when the data is not simulated but acquised, there will be not a precise amplitude and frequency valuei will it the FRF block go crazy then ?
I've tried that process with several post-processing softwares; MATLAB, dbFA Suite (A vibratory daq system interface). All results different
Do you have any suggestions to solve that? Or can it be corrected?
Regards,
Ozgur

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Nidal,
Below is an example that illustrates how to generate different sine waves on two separate analog output channels.
Example

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Hello,
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Preetham1 wrote:
Hello srikrishnaNF,
Thanks for the solution. But the issue is I just want to append one cycle of a1,f1 and one cycle of a2, f2. f1 and f2 could be DBL. Let me know if you have a solution. I shall appreciate it.
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Hello everyone,
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I am using the Order Analysis Toolkit and want to get more information about the compensation for "Reference Signal Processing", which is scarce in the manuals, the website and the examples installed with the toolkit.

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DESCRIPTIONS:
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Go to Solution.

Hi CracKatoA.
Take a look at the link bellow:
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Dear Micaela,
Thank you for advice. I will change driver to the DAQmx . But it will take time to download 460 M.
Therefore I continued with the old driver.
I changed DAQmxBaseCfgSampClkTiming to DAQmx_Val_ContSamps and immediately faced with another problem. The device began to acquire data continuously, and when I call DAQmxBaseReadAnalogF64 in the timer handler, I got the date that does not correspond to the current time. The data corresponds to the experimental parameters which were 5 minutes ago. I was very surprised until I realized that this huge delay exits!
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Message was edited by:
Hotkey_ger

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