ARTA/LIMP free software for LCR measurements with sound card

[001]

Hi

http://www.artalabs.hr/index.htm

Is it ok?

[JohnG]

I used this software quite a bit when I was more involved in audio and some related stuff (> 5 years ago). At the time, it had a lot more capability than I would ever use, but I still found it easy to use. I see it has been recently updated.

I used it primarily for speaker measurements (characterization), some amplifier measurement, some signal source characterization, etc. Depending on what you are doing, you will need to have a good soundcard, microphone(s), and will probably need to build some test jigs if you want to do some speaker measurements.

Excellent and thorough documentations with lots of theory and examples. If you are interested in acoustic measurements, I highly recommend downloading the documentation.

Since I purchased this for my last job, I paid for the commercial license, and it was well worth it to me.

John

[001]

I`m not audio man but I`m interested in coil measurments for SMPS. Is it good idea to use LIMP? 

[_Wim_]

Yes, you can use limp for that. It has an LCR function. You only need to wire in a series resistor from which you know the exact resistance. You can use the free download, only difference is the measurements cannot be stored.

The same measurement principle is used by the Analog Discovery LCR module. It is not extremely accurate, but for sure good enough for your purpose.

[JohnG]

The frequency range will be limited if you are looking at inductance for SMPS. Some of the more interesting stuff, e.g self-resonance, will probably occur out of the range of LIMP.

John

[DaJMasta]

The frequency range will be limited if you are looking at inductance for SMPS. Some of the more interesting stuff, e.g self-resonance, will probably occur out of the range of LIMP.

John

And if the software doesn't actually limit frequency range, the audio card hardware would.  Switchers are commonly at frequencies above audio band, so anything filtering to keep high frequency noise out of audio equipment will remove measurement capability in that range.  There are some sound cards that don't or which leave some ultrasonic range in, though, so it may be worth looking through the documentation for a frequency limit.

[_Wim_]

Many modern sound cards support high sample rates (up to 192kHz), and limp does not limit the sample rate, so up to 96kHz is possible.

But indeed an impedance analyser or something like the analog discovery can go much higher in frequency. But as a cheap alternative for an LCR meter which typically also stops at 100kHz, I think this is still an ok solution.
For frequencies above 50kHz a NanoVNA could be used (up to 900Mhz) 

[001]

And if the software doesn't actually limit frequency range, the audio card hardware would.

Yea. It is dumb idea. Sorry 

[Frex]

Hello,

Maybe the right intermediate between a soundcard and a VNA would be the AnalogDicovery.
I allow to trace Bode diagram and Impedance analyser between DC to 10MHz.
I used it to calibrate resonating inductive position sensor (~3MHz), i think it's an idela tool for SMPS design.
Regards

Frex

[001]

  AnalogDicovery.

It is about $300 so I`m going with my oldtimer bridge

[SilverSolder]

  AnalogDicovery.

It is about $300 so I`m going with my oldtimer bridge

The Analog Discovery software actually works with a sound card...   it is free to try.

[001]

The Analog Discovery software actually works with a sound card

How to do it? 

[SilverSolder]

The Analog Discovery software actually works with a sound card

How to do it? 

1. Download the WaveForms software and install.
2. Select "Sound Card" in the device manager in WaveForms (the one already in your PC will likely work fine)
3. Strip down an audio cable to be able to connect the sound card input/output to your experiment 
4. Knock yourself out... most features work.

The big limitation with using a sound card instead of the Analog Discovery hardware is that the sample rate is a lot lower with a sound card, so it is really only good for audio frequencies (perhaps a bit higher than that if you have a higher end sound card with high sample rates).

Another thing is -  make SURE you don't apply any external voltages into your sound card, that could be an expensive mistake.  Passive component testing only!

[_Wim_]

It is about $300 so I`m going with my oldtimer bridge

The nano VNA can be had for only <40$, and together with the lastest Nano-saver app (https://github.com/mihtjel/nanovna-saver/releases/tag/v0.2.1) you can plot L an C curves untill 900Mhz. Only starts at from 50kHz however.

[_Wim_]

Current features of the Nano-Saver software (see https://github.com/mihtjel/nanovna-saver):

Reading data from a NanoVNA
Splitting a frequency range into multiple segments to increase resolution (tried up to >10k points)
Averaging data for better results particularly at higher frequencies
Displaying data on multiple chart types, such as Smith, LogMag, Phase and VSWR-charts, for both S11 and S21
Displaying markers, and the impedance, VSWR, Q, equivalent capacitance/inductance etc. at these locations
Displaying customizable frequency bands as reference, for example amateur radio bands
Exporting and importing 1-port and 2-port Touchstone files
TDR function (measurement of cable length) - including impedance display
Filter analysis functions for low-pass, high-pass, band-pass and band-stop filters
Display of both an active and a reference trace
Live updates of data from the NanoVNA, including for multi-segment sweeps
In-application calibration, including compensation for non-ideal calibration standards
Customizable display options, including "dark mode"
Exporting images of plotted values

[_Wim_]

Or if you have any of these scopes (shameless plug  )
https://www.eevblog.com/forum/testgear/rlc-impedance-viewer-for-picoscope-bode-plot-data/msg2190516/#msg2190516

[DaJMasta]

Yea. It is dumb idea. Sorry 

Not all of them do, I've heard the older Creative EMU series don't, and I think the QA401 is limited, but a bit above the audio band.  It's not that the idea can't work, it's that it would be easy for some hardware to prevent it from working, so you have to choose carefully.