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Justin Crooks

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Viewing 20 posts - 1 through 20 (of 385 total)
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  • in reply to: Pulse analysis and PCR4200 #255579
    Justin CrooksJustin Crooks
    Moderator

    Jonathan,
    In pulse analysis, the reference signals would be predefined, either from a previous capture or separately.
    You can examine the phase and amplitude delta between PCR channels in our multi-channel mode. We have talked about expanding this feature set (for both pulse analysis and multi-channel mode). Would you be willing to talk about the features you are looking for, either here or in an email to support@signalhound.com ?

    in reply to: PCR4200 Simultaneous VSG and SA #255342
    Justin CrooksJustin Crooks
    Moderator

    Jonathan,
    Yes, using the VSG and receiver channels simultaneously is the whole point of the integrated VSG.
    It should be one connection to the instrument, and one full setup, including transmit and receive channels. A new connection to the instrument would likely reset things.
    I’m not the best person to answer, so if you email support@signalhound.com with the details of what you tried and what you want to happen, they can assist you.

    in reply to: BB60C for evaluating a wifi devices #254930
    Justin CrooksJustin Crooks
    Moderator

    In the first photo, you can see the issue is the dynamic range of the BB60C bringing the noise floor up, so you might need to decrease your reference level. In the second photo, you might have your reference level set too low – it could be compression causing the artifact. But with the BB60C, there might not be a setting where it passes both close-in and wideband simultaneously, due to its limited dynamic range.
    The BB60D gives you 10-20 dB of additional dynamic range, and the SP145 offers an additional 10 dB. These are our best products for spectral emission mask testing.

    in reply to: Vsg25a multiple signals #254876
    Justin CrooksJustin Crooks
    Moderator

    Essentially I’d just make a QPSK waveform, apply N rotations, probably in excel, maybe stagger them for a more realistic envelope, add them together and scale.

    in reply to: Vsg25a multiple signals #254874
    Justin CrooksJustin Crooks
    Moderator

    Our latest VSG60 software allows you to export waveforms. If you email me the details I might be able to throw a waveform together, as long as you’re ok with me rounding to easy offsets. justin at signalhound dot com

    I’d need to know symbol rate, root raised cosine filtering unless otherwise specified, channel count and spacing

    in reply to: Vsg25a multiple signals #254861
    Justin CrooksJustin Crooks
    Moderator

    What exactly are you looking to do? Basically anything custom is going to require some DSP tools, like Matlab or our VSG60 software.

    For the VSG25 you’ll need to choose your I/Q sample rate and pattern length so the sequence can repeat perfectly, e.g. 4 MSPS, upsample by 32 for a 128 MHz sample clock. Use a repeating pattern of e.g. 32 symbols for 1024 sample pattern length. Then you can shift the center frequency in units of 128/1024 MHz, repeat for each QPSK signal, add and scale.
    You can generate a sequence twice as long, then use the middle portion, to remove any edge artifacts.

    Note that the VSG60 does not have the same limitations, and is generally the preferred tool for applications like this.

    in reply to: Vsg25a multiple signals #254835
    Justin CrooksJustin Crooks
    Moderator

    The challenge with the VSG25A is keeping your signal to <=2048 repeating I/Q samples. There's no reason you couldn't have 2 to 8 QPSK channels if they're ideally spaced and playing a short repeating sequence (Maybe 16-64 symbols would be a maximum). The VSG60 or VSG200 could handle much more complex (and arbitrarily longer) sequences, but 40 MHz of bandwidth is all you get.

    in reply to: Laptop Requirements for VSG200 & SM435B #254816
    Justin CrooksJustin Crooks
    Moderator

    It looks like a good processor. And I see Thunderbolt ports and a USB 3.2 type A. That should be everything you need to run the VSG200 and SM435B simultaneously.
    That being said, we have seen occasional makes / models that should be able to run multiple devices simultaneously but still struggle, and it can be difficult to predict. But this laptop looks like a solid choice.

    Justin CrooksJustin Crooks
    Moderator

    Thanks for pointing this out. I’ll make sure the software department sees this.

    in reply to: VSG200 Bandwith Combination #254475
    Justin CrooksJustin Crooks
    Moderator

    Yes, the wider bandwidth next generation VSG will include a trigger in/out.

    in reply to: Copy Marker Value #254458
    Justin CrooksJustin Crooks
    Moderator

    Jay,
    You can automate marker readouts using our SCPI library, but you cannot copy the text directly from the screen.

    in reply to: VSG200 Bandwith Combination #254439
    Justin CrooksJustin Crooks
    Moderator

    Pedro,
    We are actively gathering requirements for our next gen VSG line, with considerably more bandwidth. If you had to pick a bandwidth, what would you want, knowing that higher bandwidth generally increases cost? And how big of a waveform (in milliseconds) would you need? Single channel or multi-channel?

    in reply to: LabVIEW Device not open #254372
    Justin CrooksJustin Crooks
    Moderator

    CJobbers,
    Hopefully our support team was able to help you. If not, reach out to support (at) signalhound (dot) com for more direct support.

    in reply to: Spike on macOS #254294
    Justin CrooksJustin Crooks
    Moderator

    Damon,

    You can download Spike for Linux (Ubuntu and Red Hat). The SA- products are Windows only, but BB- SM- and SP- products are supported under both.
    https://solutionspagedemo.kinsta.cloud/spike/

    in reply to: Viewing and analysing 32APSK DVBS2X modulated signals #248667
    Justin CrooksJustin Crooks
    Moderator

    Something like the BB60D would work well for this application. If you are still in your 30 day return window, reach out to support@signalhound.com

    in reply to: Running VSG60A on Raspberry Pi 4 or Other AARCH64 Systems #248528
    Justin CrooksJustin Crooks
    Moderator

    Nom,
    Unfortunately the VSG60A requires the SIMD registers of the x86-64 architecture. We are adding limited AARCH64 support for some of our spectrum analyzers, but the VSG60A will probably not be ported.

    in reply to: Noise Figure Measurement for Downconverter #248512
    Justin CrooksJustin Crooks
    Moderator

    llevitt,
    I’ve never tried this, but here are my initial thoughts. It seems to me that if you mapped your noise source’s ENR from RF to IF frequencies, then mapped the result back to RF frequencies, it might just work. It probably requires that image responses are sufficiently filtered, and that gain + ENR is in a reasonable range (15-35 dB?) to reduce the effect of the analyzer’s noise floor and compression.

    in reply to: Scalar Network Analysis for Low Frequency with TG124A #248450
    Justin CrooksJustin Crooks
    Moderator

    Garth,
    Yes, if you wanted to do this programatically, you could use the sa_api and tg_api. Do 2 sweeps, one with your reference through, and one with your DUT. For each point within the sweep, tune the TG then do a small (100 kHz span or smaller) sweep around the signal and find the max value. Subtract the 2 sweeps for your insertion loss. We created a support ticket for this issue, but I don’t know where it is in the queue, so a “DIY” TG sweep might be a good solution in the short run.

    in reply to: Scalar Network Analysis for Low Frequency with TG124A #248431
    Justin CrooksJustin Crooks
    Moderator

    Devjack,
    We are looking into this. It does look like we clamp to 1 kHz in this mode, which I can see does not make sense for your measurement, especially since the TG itself has 10 Hz resolution.
    Two potential workarounds while we investigate:
    1) You can use linear interpolation to get a good estimate of the 3 dB points
    2) You can exit scalar analysis mode, and just do a sweep with max hold. Then step the TG in finer steps using the TG control.
    I apologize for the inconvenience.

    in reply to: Spike 4.03 phase noise is unlicensed #248406
    Justin CrooksJustin Crooks
    Moderator

    I believe the base license (without cross-correlation) is $99 / year. If you don’t need the new features, you can keep using your 3.xx version for free.
    https://solutionspagedemo.kinsta.cloud/products/advanced-phase-noise-measurement-tool-kit/

Viewing 20 posts - 1 through 20 (of 385 total)