AD2 acquisition sample & FFT point sizes

[SL01]

Hello,

I am doing audio work and only require a bandwidth, including FFT, of up to 110kHz . I have the following questions:

 

1. What is the right way to set the AD2 so it can provide the maximum number of samples, i.e. to go higher than 8192 in real time, non-RIS mode?
2. What is the maximum number of points in the FFT? Can it go higher than 8192? 4097 bins is a little limiting.
3. Is there a way to snap the vertical cursor to a harmonic of the fundamental, especially when under measurements, the FF can be set?
4. Is there a way to switch the cursor to horizontal to measure level?
5. Is there a way to place markers with the data labels inside them on harmonic peaks?

Thanks.

 

 

[jpeyron]

Hi @SL01,

I have tagged the engineer that will be able to give you the best response to your question( @attila).

cheers,

Jon

[attila]

Hi @SL01

1. In WaveForms setting/Device manager the AD 2nd configuration allocates 16k samples for scope channels.
For low acquisition rate (<1-2MHz) you can also use the Record mode (option after the run button) to get up to 10M samples. The FFT will be slow with such huge number of samples.
2. The scope FFT will use all the available time domain samples.
3. There is no dedicated cursor option for this. However the vertical quick measure, activated from top-right edge of the plot, sticks to FFT peaks.
4. Y cursors is only available in the scope time plot. You could use the free quick measure for x and y measurements.
5. No, but for presentation purpose you can add labels to plots.

[SL01]

HI @attila,

Thanks for your replies.

1. I cannot find the Record mode. Is it because it is not enabled in Demo mode?
2. OK
3. I can find and use the Vertical measure and but it only stick to the first FFT peak, not a subsequent harmonic or an arbitrary peak. The fundamental peak is much easier to snap to manually than harmonic peaks since they vary in amplitude quite a bit if not averaged. Is there a way make the vertical measure snap to harmonic peaks also? It takes a very long time to precisely line up harmonic peaks manually.
4. Y cursors would be particularly helpful if there is no harmonic or arbitrary peak mapping.
5. Perhaps this can be a future feature? Static labels are not useful, any label should be placed where the peaks go, just like the Vertical and Free measure now.

I look forward to your

[jpeyron]

@attila I re-tagged Attila to ensure that it notifies him.

[attila]

Hi @SL01

1. See: 

3,4,5. I will try to add such features for the next software version.

[SL01]

Hi @attila, @jpeyron,

Thank you - I sent a more detailed PM to @attila with some additional comments.

Steve