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Jubayer,
Setup for this type of measurement would be something like:
RBW 100 Hz, VBW 10 Hz, detector settings power, average. Center frequency 7 KHz, span 10 kHz. Reference level -50 dBm.
A 3.3 uF DC block should be reasonably flat down to 3 kHz or so.
Let me know if this works for you.Ed,
Depending on your serial number, there is a design flaw where under certain conditions the DC blocking cap on the preamp builds up a charge and blocks all signals. Any return path to ground for current will remedy this (including a non-zero attenuator setting).
We can issue an RMA to repair this as well (we add a small resistor). Contact support at signalhound dot com for more information. May 14, 2018 at 10:57 am in reply to: TG 124A with BB60A, AND suitability to use with other gear for immunity testing. Julian,
The BB60A will need firmware version 5 to be compatible. You can download it here: https://signalhound.com/support/product-downloads/bb60c-bb60a-downloads/The TG124A being used as a standalone generator, and amplified/modulated appropriately, should probably work for immunity testing. Depending on your needs, you may wish to low pass filter the TG output as it tends to have higher harmonics than a dedicated signal generator. You would probably want to automate it using our TG standalone API, which you can get from https://signalhound.com/products/usb-tg124a/
AJ,
I remember running into this before. I think this is the bug fix:
https://stackoverflow.com/questions/11775185/open-a-com-port-in-c-with-number-higher-that-9
Also, here:
https://support.microsoft.com/en-us/help/115831/howto-specify-serial-ports-larger-than-com9Maksym,
The power of 2 downsample factor sets the theoretical bandwidth that is available. For example, a downsample factor of 4 gives you 10 MSPS, which theoretically represents 10 MHz of bandwidth. But you should leave 20% for filter rolloff, etc. so generally bandwidth will be 40% to 80% of the total bandwidth based on your downsample rate.Using our legacy API, the device can be configured to use the 2.9 MHz IF (hung mixer mode). You would have to use a higher frequency than 5 MHz (something like 15 MHz at least). I’m not sure it would get you significantly better numbers, but it might give you a few more dB.
There is probably enough RF-to-IF leakage in the mixer that you could use this mode (SHAPI_Configure, use 2.9 MHz IF set to true) and inject your signal directly at 2.92 MHz (at a higher amplitude). This is the closest to direct ADC access the SA series offers.
These are just my thoughts, and may not work, but if you give it a try let me know what you find. The BB60C has more direct ADC access, but realistically, the SM200A would be the ideal choice.
The BB60C has a built-in DC block. We correct amplitude down to 9 kHz, but there is a lot of VSWR below 100 kHz, making scalar measurements difficult
Mehran,
We typically need to evaluate the market demand for something like this before we commit to implementing it. And then there is a timeline for feature requests. It rarely happens in a few days unless you have placed a very large order and it is a very simple feature.
If other users chime in requesting a similar feature, the priority gets bumped up. Otherwise, we will evaluate it and make a decision as time permits.
Because of the BB60C architecture, its phase noise, especially at low frequencies (e.g. below 1 GHz) is not very good. So we decided to disable phase noise measurements rather than provide poor results.
The SM200A is recommended for phase noise measurements inside 100 kHz offset. The SA44B can make pretty good phase noise measurements as well, especially outside 100 kHz offset.Pritam,
Our API supports a maximum of 8 per computer. Keep in mind that the USB high speed bus is a shared bus, so you probably can’t even have 8 SA44B devices all streaming at the same time, unless you were decimating the data heavily.A possible setup, if you need 24 USB-SA44B’s simultaneously streaming to one PC, would be to have 7 PCs in a network. Use 6 PCs to connect to 4 SA44B’s each, and each stream their data to the 7th PC. It would be a bit of a project, but any project that requires 24 spectrum analyzers is going to be a bit of work anyway.
Yes, the VSG25A would work well for this.
Here is a picture. There is a connector that comes up through the case to power the fans. There are 6 fans, each 23 dB(A). I believe it can be replaced by the user, since you do not have to open the main enclosure to replace them. The fans are kept off until the FPGA reaches a certain temperature (I believe 50C), and then they turn on (until the FPGA is below 30C), and I believe the fans turn off for phase noise measurements.
Let me know if you have more questions.Out of curiosity, what type of functions would you be interested in adding? Is it something many users would benefit from, or something specific to your application?
We have an API for the SA44B that allows it to be used with a Raspberry Pi 2 (and probably on newer versions as well). It is kind of hobbled in this mode, but you can do some basic sweeps and probably even stream 40 kHz of decimated I/Q if you wish. You would be responsible for the software though.
For using Spike, an Intel NUC running Windows can be useful if size is a concern.
Our noise figure is higher than this, so you would have to use a preamplifier with the BB60C to meet this noise figure.
Typical noise floor for the BB60C at 800 MHz is around -163 dBm/Hz, so the noise figure is around 11 dB. At 2.4 GHz, typical is -159 dBm/Hz, for a noise figure of 15 dB.
I suppose SNR for the BB60C depends on a lot of things, but a good starting point might be about 44 dB for a 2 MHz signal bandwidth, including phase noise and thermal noise, if I made my measurement correctly.
FSK demodulation should work fine for MSK signals
I know of people who have tried this. The short answer is that you *might* break something as you could potentially back-power the USB, but I have not heard of anyone actually breaking something. If your charger puts out a clean 5 V, in theory it could extend your battery life if you had enough watt-hours in your charger. If it is not a clean 5V, it could do bad things, and it might do bad things when its charge runs out.
Does your laptop manufacturer make a higher capacity battery? Or a replaceable battery?
From the thread you linked to:
“The TG44 can be used as a standalone generator. There is an application called TGStandalone in the Spike application installation directory which allows you to set the frequency and amplitude of the generator.”
You can also set the TG frequency and amplitude using a TG standalone API, available on request. There are no modulation capabilities, just a CW. The TG output has a lot of harmonics, so a low pass filter should be used if you use it over the air, and you should make sure to adhere to any regulations regarding over the air RF transmissions.Yes, it looks like the attenuator is broken. You can email support@signalhound.com for information on repairs.