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I can’t provide schematics, and opening the case will void the warranty. But there is a 10 MHz TCXO on the board. We have a software correction for its measured frequency though, which might make it challenging to do what you want.
Matt,
Unfortunately we do not have a STEP file for our SA-series. The closest would be the BB60C, but the SA44 is 1 inch shorter, uses a USB 2.0 type B, and has a slightly lower SMA output.
https://signalhound.com/wp-content/uploads/2024/02/5146-9941_BB60C_defeature_artwork.STEP_.zipEduardo,
Can you measure the signal just fine using the Spike software, and are trying to automate it? If so, read through our SCPI documentation in the SDK and let us know how you’re trying to connect (socket / VISA) and what errors you’re seeing. https://signalhound.com/news/scpi-automation-of-signal-hound-spectrum-analyzers/ABorel,
I’m not sure what you’re doing on the receive side, but something like the BB60D, using the digital modulation analysis tools, would be able to lock on and demodulate the (amplified then attenuated) QPSK waveform, and give you an EVM (error vector magnitude) related to the linearity of the amplifier. It can be fairly tricky to check your I and Q symbols without some sort of digital modulation analysis, as there is a delay and phase rotation between the transmitter and receiver, even on the same time base.Kaiser,
I’m curious about the coordinating of the two SM’s. Are they both producing a GPIO output that the FPGA is using to coordinate the signal generation? Do you monitor the two GPIO outputs continuously? Does the bug follow e.g. SM #2 trigger arriving before SM #1? Or SM #2 getting a full sweep ahead or behind SM #1?
Our sweeps are not deterministic, so I can certainly see some variance in timing between the two SM’s playing a role in this.
If you could use something like I/Q streaming, and have the FPGA generate the trigger, or have SM #1 sweeping and generating the trigger and SM #2 streaming at one of the frequencies with a trigger input, something like this might be more solid. Just my thoughts…Good news. Thanks for the update, and for sharing what fixed it!
One thing to try is the CDM Uninstaller with VID 0403 and PID 6010. Sometimes the first install goes south on a particular computer and this is the only way to get it functional. https://ftdichip.com/utilities/
MGielen,
If you can get Serial Converter A and B to show up, the next thing to check is if the VCP driver is being loaded. It should *not* be loaded, as it is not compatible with our firmware.
The VCP Driver can be unloaded by going to Device Manager –> USB Controllers –> USB Serial Converter A –> Advanced, and un-checking the “Load VCP” box, then repeating for Serial Converter B. If this does not work, please email our support team.
The SA124B should be used with a Y cable to provide extra power. If you are using a standard USB cable, especially with a laptop, it may not be getting enough voltage. 4.75V at the SA124B is ideal, but it will operate down to 4.5V. Below 4.5 volts there will be issues.Unfortunately the TG44A only has a 10 MHz output. You can use this for 0 ppm relative accuracy between the TG and SA, but for absolute accuracy, you would need a TG124A or VSG60A instead of the TG44, both of which can accept a 10 MHz input. The phase noise on the VSG60A will be much, much better than the TG124A.
Ed,
If you email support (at) signalhound, we can send you the BB60C Statement of Volatility.
To sum up, the onboard flash is used only for firmware and correction data. All instrument state and waveform capture data is stored on the PC.Thank you for your suggestions! I’ll forward them to the software team.
To clarify, the phase noise of the OCXO itself, at a 10 Hz offset, should be better than -105 dBc/Hz. Generally to measure these numbers, a phase noise tester will need a significant number of correlations.
The OCXO is only for frequency stability. It does not affect the phase noise specification (there may be a slight improvement close in). An external reference can also be used for improved frequency accuracy, especially if the external reference is disciplined to GPS.
EHackett, if you are having this issue on a brand new unit, and followed the network configuration / troubleshooting guide without success, definitely reach out to our support team. We should be able to either help you resolve the issue or set up an RMA.
I can’t think of a way to make that work. Unfortunately the SA44B triggering is really only for the tracking generators. Although we have not implemented it in firmware, the SM200 / SM435 would be capable of exporting a video trigger as a logic signal, but the BB and SA series would not. That being said, a detector diode and a comparator could generate a trigger off of a certain RF amplitude…
Ewald, I’m not sure if it would void the warranty or not, but it might. There is a ribbon cable that has 12 V power for the fans, connected internally, and you would not want to risk that shorting out. Your safest bet would be to contact support (at signal hound dot com) and we could set up an RMA to convert it to a passive cooling option. You can remove the heat sink on the passive units without voiding the warranty.
If you just need to stop the fan noise, you can set the temperature threshold higher rather than removing the fan assembly.It is a hardware preselector (band pass filter before any amplification or mixing). There are 12 bands but only 10 of those are true preselector bands. DC-30 MHz is direct to ADC, and 30-130 MHz is a push-pull amplifier.
The DC block will only affect signals below 100 kHz. Remember when you connect an antenna to use ESD precautions (i.e. ground yourself to the case before and during any antenna adjustments)
Our accessory kit includes a 20 dB pad, which is enough to make measurements up to 1 watt (+30 dBm). As long as you attenuate enough to keep your signal below +10 dBm, and set your reference level to +10 dBm, and your attenuator is rated for the input power, you should be fine.
Jason,
I’m glad you found a workaround. The TG44 is occasionally a challenge to connect the first time, but the Spike software tends to connect easier on subsequent cycles. Hopefully this is your experience as well.