Hi hhonza,

Try disabling the video trigger when you are playing back the capture. This will allow you to scroll through the data. When you are playing the signal back and the video trigger is active, it attempts to find triggers in the capture and overrides your manual scrolling.

Once you are able to scroll through the data, try zooming in on the falling edge of that pulse to verify it is a smooth descent.

The trigger position control only affects the display of the IQ data. The pre-trigger setting on the IQ recording toolbar affects how much data before the trigger gets saved.

Let me know if you have additional questions.

Regards,
Andrew

(Yves has contacted us through email)

– Andrew

Hi John,

Sorry for the delay in response. The SA44B can sweep a larger range than its available RBW. The SA44B can be configured to sweep any range of frequencies within its 1Hz to 4.4GHz range. At a 200MHz span the minimum RBW available will be 6.5kHz.

As for antenna, I’m not familiar with the EMI/EMC antenna market. I would imagine it would depend on what you are attempting to achieve. Are you simply trying to find/characterize interference, an RF probe might be best in this case. If you need to simulate a real EMC test, you will likely need to recreate the test setup as close as possible with a calibrated antenna. I wish I could be more help. Maybe someone else on the board could help you out? You could create a separate topic. I know there have been several users on this board with EMC experience.

Regards,
Andrew

[Andrew]

Hello pmerana,

In the control panel in EMC precompliance, in the ‘trace’ section, you will find the export button which will export the entire sweep (all active sweep segments) to one file. It will export the frequency/amplitude pairs of each sweep segment in order. (Basically exactly as it is plotted). You will need to plot it on a logarithmic x axis to see it as it is shown in Spike. Is this adequate for your needs?

No updates for automatic QP measurements.

Regards,
Andrew

• This reply was modified 7 years, 7 months ago by Andrew.

Hi Blackmore90,

IQ streaming can be more USB throughput sensitive than standard swept analysis.

Here are some troubleshooting ideas.
1) Try a different USB 3.0 port. We have found that not all USB 3.0 ports are created equal.
2) Enable the high performance power option in the “Power Options” menu in the control panel.
3) Try updating your USB 3.0 driver. You can find instructions for Windows 7 machines on our website on the page http://www.signalhound.com/Spike in the FAQ section under the question “The Software Reports “Device not found” (BB60C)”. You will find two driver links. Install one and restart your PC and try again.

I look forward to your response.

Regards,
Andrew

Hello HHonza501,

There are no plans currently to allow the user to change sweep configurations during the recording. If users needed this kind of flexibility on the sweep recordings I would recommend using the API to retrieve sweeps from the device and storing them in a custom file format that suits the customers needs.

You are correct, as you scroll the recording it will move the sweeps into the waterfall. I can see how this wouldn’t be desired. I will make a note of this and potentially resolve this for future versions. Thank you for the feedback.

Let me know if you have additional questions or need clarification.

Regards,
Andrew

That is correct. There is no configurable DSP on the unit, other than the processing associated with individual measurements (sweep/real-time/IQ). The API will be very similar to our other devices.

Regards,
Andrew

Hi Testpoint,

More information on the SM200A here
https://signalhound.com/sm200a/

Let us know if you have follow up questions.

Regards,
Andrew

Hello Sinisa,

Currently there is no plan to restore the 3D waterfall.

Regards,
Andrew

Hello Bindinir,

The 3D spectrogram view was removed in a recent release. In that same release we added several new features to the 2D spectrogram, such as large sweep history and marker placement.

I apologize for the inconvenience. If you have additional questions for feedback, please let us know.

Regards,
Andrew

Hi Jay,

We have seen improvements when using a low latency or real-time kernel. Unfortunately there is no way to determine when this loss occurs. At one point we narrowed it down to a small circular buffer within the FTDI driver, (based on other similar complaints). Several years ago we tested an open source version of the FTDI driver and saw worse results.

Internally using a low latency kernel with a desktop PC (Intel i-series processor), we saw no loss occur over long periods of acquisition (using IQ data to detect data loss). Although, I have had customers report data loss even on low latency kernels with lower power processors.

It would require a moderate/large firmware/software redesign to fully resolve this issue for the Linux platform. We don’t have any plans for this at this time.

Regards,
Andrew

Jay,

Are you by chance on Linux? I have seen what you describe on Linux, not on Windows. On Linux, the FTDI USB driver does have throughput/buffer issues for high throughput devices.

If you are on Windows, do you know which error code is being returned? The problem corrects itself on the next sweep? You could try a couple troubleshooting steps we suggest for customers who are having USB issues, such as, enabling the “High Performance” power plan in the “Power Options” control panel menu, and disabling any anti-virus you might be running.

Regards,
Andrew

Hello Petr,

This is possible, you will need to generate a custom IQ file for this output as we don’t have the amplitude offset functionality build into the pulse gen controls.

If you look in the VSG25A installation directory you will find a number of example IQ files which follow the format you can easily load into the VSG software. You can edit them with excel or any text editor easily to create your desired waveform.

Let me know if you have additional questions.

Regards,
Andrew

Hi Jay,

Thanks for the follow up. I’m glad you got it working.

The official message you will see when the input level is too high is saCompressionWarning(2). If you have any questions about this, let me know.

Regards,
Andrew

Hi testpoint,

DANL is specified at 0 attenuation and max gain (maximum receiver sensitivity). If you set your reference level to -50 the BB60C will be configured for maximum sensitivity and you will see the DANL you expect.

The way our software currently works, is that the sensitivity (atten/gain) is configured automatically from the reference level. You can control the gain/atten manually in the control panel, you will need to disable the lock on those controls in the file->settings menu (or F11).

Let us know if you have additional questions.

Regards,
Andrew

Hello jthienel,

Ensure that both gain and atten are non-negative. Any negative number will cause the device to select the gain/atten automatically.

If you are interested, setting the gain/atten to automatic (-1) the default condition, the reference level set in saSetLevel() controls the gain/atten automatically optimizing for signals at or near the reference level. For example, if you know your input signal is -20dBm, setting the reference level to -15 will optimize the device for your measurement. You can get much more consistent results with this method. Maximum sensitivity is achieved with a reference level of -50 or less.

Let me know if you have additional questions.

Regards,
Andrew

Hello Marzelozz,

In the latest version of Spike, you can place markers on the waterfall plot and measure the time difference between two peaks. You will need to download the latest version of Spike from the Spike landing page here
http://www.signalhound.com/Spike

If you have questions after installing this and trying the measurement, let us know.

Regards,
Andrew

Here is a link to the article if you are interested.

http://www.microwavejournal.com/articles/28984-high-performance-20-ghz-spectrum-analyzer-and-monitoring-receiver?utm_content=bufferc23b5&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer

Hello Hhonza501,

Yes, you can launch 2 or more instances of Spike on a single computer. For the BB60C, each Spike instance will alert you that there is more than 1 device connected to the PC and you will need to select a device from the File->Connect menu to open it. When you launch the second Spike instance, just ensure you pick non-opened device. If you try to open a device twice, the second application will ‘steal’ it from the first. (The first instance will see a device disconnect)

Keep in mind 2 or more Spike instances share presets and preferences.

With the BB60C, two or more instances of Spike can consume a lot of resources. You may run into issues on low power ultrabooks or similar. I wouldn’t expect any issues on a standard desktop i5/i7.

Let me know if you have additional questions.

Regards,
Andrew

Hello Mirek,

Thank you for the follow up.

Regarding the sweep time, I did forget that the SA44 and SA124 units do behave slightly differently. Unfortunately, the SA44/SA124 do not have a selectable sweep time, mainly because there are heavy restrictions on how the unit sweeps which limits us to very specific configurations for given RBWs and spans. These limitations are in hardware/firmware. Because of this, the sweep time parameter is ignored for these devices. Additionally the sweep time printout on the graticule is updated each time the screen is refreshed with new sweep data. So yes, as you mention, for the wide and long sweeps on the SA44/SA124 this number will not represent the total sweep time. Apologies for the confusion. For our BB60C and for narrower sweeps in the SA44/SA124, then the sweep is updated in its entirety each screen update and thus that number is more representative of the overall sweep time.

Regards,
Andrew

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