Portable scope with good FFT

[radhaz]

A requirement for measuring frequency in the audio spectrum at installation sites came up at work. The device to be measured is a vortex flow meter's raw flow sensor signal.  In the lab I use a Keysight MSOX3014T for this purpose, so a portable device that approaches that functionality is what I would be interested in.

[stmdude]

Have you looked at the Keysight 1000X ?

It would feel very familiar, and it does have FFTs.  It's light and has a handle, so that qualifies as portable, right ?

[lem_ix]

Check out the Micsig to1104, or a lesser model from the series, doesn't get more portable than that. Can probably find some tests of the fft function here https://www.eevblog.com/forum/testgear/micsig-tablet-oscilloscope-tbook-mini-to1000/

[radhaz]

It would need to be battery operated, the installations are sometimes difficult to access.

[don.r]

Micsig has a battery option.

[nctnico]

I second the suggestion for the MicSig TO1000 (with the battery option).

[radhaz]

The suggested Micsig looks useful. Would any owner of the scope show me fft sweeps from 0 to 3kHz?

[JPortici]

if all you're looking at is audio frequencies, how about your laptop/tablet/phone + audio interface + your software of choice? even with the crappiest audio interface you will have better dynamic range and resolution than probably any oscilloscope at those frequencies. Also a bunch of processing power and and whatever frequency resolution you want.
you are not limited by what the embedded scope software lets you do

[radhaz]

The signal strength of the piezo crystal in a vortex flow meter is in the millivolt range at it's low end of around 300Hz. There is also a tremendous amount of environmental noise (mechanical, electrical). The environments can be quite harsh and difficult to access.The form factor of the tablet looks suited to this task.

[alm]

If the signal is very noisy, the low vertical resolution of a scope might not be the best tool for the job (especially if you want to avoid the signal from messing up your frequency response by over driving the inputs). Something like a high-resolution Picotech scope or the already proposed audio interface might give you better results. Or possibly an external analog filter.

[Rich@RohdeScopesUSA]

You might check out our handheld RTH1000. It comes standard with a good FFT and you can add a spectrum analysis capability that uses digital down conversion. It also has a 10-bit ADC.

https://www.rohde-schwarz.com/us/product/rth-productstartpage_63493-156160.html

-Rich

[nctnico]

If the signal is very noisy, the low vertical resolution of a scope might not be the best tool for the job (especially if you want to avoid the signal from messing up your frequency response by over driving the inputs). Something like a high-resolution Picotech scope or the already proposed audio interface might give you better results. Or possibly an external analog filter.

The MicSig tablet scope has input filtering. Besides that if a signal has a lot of noise surrouding the signal of interest then FFT won't do you any good.