Measuring frequencies present in an analog signal

Hello,
I want to measure the frequencies present in an incoming analog pulse signal.
I tried it as shown in the vi using ‘Extract single tone information.vi’ which was showing the value as ‘39m’ I dont understand what is this value. Can someone explain the right way of measuring the frequencies present in the signal so that I can feed them to my bandpass filter limits.
Thanks.
Solved!
Go to Solution.
Attachments:
Measure_Frequency.vi ‏102 KB

Hello,
The acquired analog signal is pretty much filtered as shown in the attached image.
Now I am collecting data for 5 seconds (collecting 2500 samples using collector.vi ) and finding the single tone frequency from it and plotting the measured frequency after 5secs in a waveform chart.
But I am confused with these1)The original detected signal has an amplitude of above 1.6V but the measured amplitude only shows 0.6V and 2) how the waveform chart has a plot plotted over the duration of 5seconds when the frequency is measured for every 5seconds data I mean shouldn’t the chart has a plotted value of HeartRate plotted for every 5 seconds.
Can someone explain a bit about these.
Thanks.
Attachments:
Freq.JPG ‏74 KB
Frequencyplot.vi ‏94 KB

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Attachments:
timing signal 1.JPG ‏44 KB
timing signal 2.JPG ‏47 KB
daqmx gen.JPG ‏55 KB

Hi David,
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10MHZ
100G s/s
100KHz
100MHZ
10MHZ
100G s/s
10KHZ
1GHZ
1MHZ
100G s/s
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10GHZ
10MHZ
100G s/s
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100GHZ
10MHZ
100G s/s
10MHZ
100GHZ
10MHZ
100G s/s
5MHZ
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NI9411 wrong frequency measurement of flow sensors / 24 impulse signals

Hello Ni Forum,
I already searched for similar problems, but haven't found anything helpful. So I'm posting our problem here. I'm apologizing in advance for bad english, it's not my mother tongue
We're encountering some strange behaviour of our NI9411 Module. We're using it in a Compact Rio with some other modules (2x Analog In).
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LabView
ideal values
Flow Sensor 1
Flow Sensor 2
Flow Sensor 1
Flow Sensor 2
4600
12200
740,6
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Puls-Measure-VI is attached beneath.
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Attachments:
vi.png ‏20 KB

Dear Lynn,
thank you for your reply. The impedance was an issue that our local technical distributor already suggested to check. According to the datasheet of the flow sensor (see attachement) it can drive a current of 25mA. The signal generator we used is a test generator that can be used instead of the flow sensors to check the any evaluation unit the sensor is connected with. So it should generate signals that are equal to those the sensor would have generated. And even with this the frequencies measured with LabVIEW are not as expected.
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Attachments:
block diagram signal amplifier and signal description.png ‏151 KB
technical data.png ‏124 KB

Determining Analog Signal Frequency with Prebuilt VIs

Don't know what is wrong with this code. Am trying to determine the frequency of a signal from an analog signal (paddlewheel flowmeter). As a starting point, I'm using a simulated square wave with the "Timing and Transition Measurements" VI and am getting following error:
~~~~~~~~
Error -20308 occurred at Timing and Transition Measurements -> frequency_determination_example.vi
:3" (waveform index 0 of 1)
Possible reason(s):
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~~~~~~~~~
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Attachments:
frequency_determination_example.vi ‏101 KB

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DigRandFreq.png ‏62 KB
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Solved!
Go to Solution.
Attachments:
pwm.out.in.analog.out.in.vi ‏45 KB

Dear nathand thanks for your reply,
i have ran the vi again and i am have error no 50103 from the (AI, number 3. ) but it is not displaying the error message, the VI keeps running without any error notification.
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Measuring frequencies present in an analog signal

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