PicoLog and 4-channel oscilloscope

Forum for discussing PicoLog
Post Reply
Posts: 0
Joined: Sat Jan 06, 2018 12:07 pm

PicoLog and 4-channel oscilloscope

Post by horsevad » Sat Jan 06, 2018 12:27 pm

I am in the process of researching the effects of stray currents on livestock farms. I use a wide range of your oscilloscopes and self-programmed FFT-analysis for the research.

However, for further analysis I need the ability to log several days waveform data (preferably in a format analyzeable with PicoScope software or possibly in .csv-format for further statistical analysis in CRAN-R) from a 4-channel oscilloscope. The PicoScope 2405A seems perfect for the measurements, as the frequencies found in this application never exceeds a few MHz's

I have read about your "PicoLog" software; but in the download section this is only available for 2204A and 2205A.

My questions are therefore:

1: Does the PicoLog software work with the PicoScope 2405A ?

2: Or is it necessary to let several 2205A do the measurements parallel to achieve 4-channel datalogging?

3: Can you confirm that the PicoLog software can record for several days?

4: Can the stored data be imported in the PicoScope software?

5: Can the stored data be exported to .csv (or similar)?

Thanks in advance!
//Kim Horsevad

Posts: 426
Joined: Mon Aug 11, 2014 11:14 am

Re: PicoLog and 4-channel oscilloscope

Post by Gerry » Tue Jan 09, 2018 11:30 am

Hi Kim,

If you need to cover a bandwidth of a few MHz then that means you would need a sample rate of 10MS/s or greater (to avoid gross errors in the resulting data waveform). At those sort of sample rates (using the PicoScope 2205A, our fastest data acquisition device for PicoLog) you have to use block mode in PicoLog (or PicoScope), which limits the total collection time to a micro second. If the integrity of the resulting waveform is not so important, then you could relax the sample rate requirement, however, even at, say, 5MS/s (to avoid aliasing, which could lead to complete misiinterpretation) the same restrictions apply.

The only possible way to perform what you ask would be to stream the data from the 2405A to the computer using our Software Development Kit (you would be able to stream at any rate up to just over 30MS/s) but then you would be limited by the random write-to-file speed of your mass storage media. In any case, several days worth of logging at a sample rate of 10MS/s amounts to something of the order of 3 trillion samples, which would be a large undertaking to sift through in order to process.

You mention that you are interested in stray currents, which suggests that perhaps a better method of acquisition would be to use triggering rather than streaming (logging). You can set the PicoScope up to capture the event when it happens, and automatically write the data to a file when the capture is complete (without knowing exactly what the source of these stray currents is and what their waveforms would look like it's not possible to advise you any further on the capture of the data).

For completeness, to answer your questions:

1/ Unfortunately the PicoScope 2405A will not work with PicoLog

2/ You could log the data with 2 PicoScope 2205A's. However the data would be collected as 2 sets of non-synchronized data, because the clocks used for sampling on the hardware are independent, and the triggering would also be indepenedent.

3/ PicoLog 5 can log data for several days. However, it can only log up to 1,000,000 samples per session, which means that to continue logging you have to close the data file and open a new one (which takes seconds). So for sample rates of more than 100s of kS/s you would have perceivable gaps in your data between files.

4/ PicoScope 6 can only open psdata files for analysis.

5/ Yes, the stored data can be exported to csv format files.


Technical Specialist

Post Reply