Hi Bill,
Very fascinating behavior. From the measurements point of view, nothing changes with the dialog active. Sweeps are still polled at the same speed, etc. The dialog being active could trigger other system behavior, maybe the system is giving increased CPU resources to our application with the dialog entry open, or something like that.
If you change the start freq from 10Hz to 100Hz or even 1kHz, does the USB error go away? The 10Hz start frequency requires a large continuous acquisition, and if your system was barely meeting USB throughput, that might push it over the edge.
Things that can affect USB throughput,
– Ensure your PC is set to “High Performance” power options. See the picture on my reply in this forum post. https://productbundlesdemo.kinsta.cloud/support/forums/topic/vsg60a-stability-in-cw-mode-versus-multitone/
– Disable any anti-virus temporarily.
– If the BB60C is connected through a USB 3.0 hub, try removing the hub as a test.
– It sounds like your test setup is using another USB device. If that device is also a high USB usage device, that could be contributing to this.
– Keep your laptop on wall power.
In general I would not expect the auxillary power cable not being plugged in to result in data loss, but its possible. Does plugging it in resolve the issue? There is a separate low voltage warning you would see, and you might see sagging measurement values if power was an issue.
I look forward to your response.
-Andrew
