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Signal Generation ambiguity

Hello,

 

What is the unit on the entry "time" in the block SinWave below: sec, msec, etc. - this detail deosn't specified in help.

Also when I change history length in the WaveForm chart, the appearence of the waveform doesn't change (still 10 periods), so isn't clear what is exactly generated

 

Thanks

 

sin_generation (0).png

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Message 1 of 5
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The entry is whatever you want it to be -- it is dimensionless, but is the "t" of wave(t) = sin (2*pi*f*t).  Note that the units matter when you compute the sine function, since the sine argument is also dimensionless.  Thus if you express the frequency, "f", in Hz, you need to express time, "t", in seconds (so Hz * sec = 1/sec * sec = 1).

 

Bob Schor

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Ok, thanks Bob,

 

What about units on X-axis of Waveform chart.

The appearence doesn't change if I modify history lenght - Xmax - Xmin is always 100.

 

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In this VI (please, see below) I try to generate 50Hz.

The loop runs every 1ms, so during period loop makes 20 points (a sufficient number to recognize waveform, isn't it ?).

Instead I see this:

50Hz generation.JPG

 

Any comments ?

 

Generate 50Hz (0).png

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I think I have found the answer - to conform to loop delay units - the divisor in divide module must be 1000 (instead of 1) because loop delay measures in ms.

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