Hi Peter,
At 100kHz and below spans for the scalar network analyzer (SNA) sweeps, the device allows more time for the signal to settle, as many of our users are measuring narrow band devices with higher settling times. Setting the span above 100kHz (e.g. 105kHz), will prevent the devices from going into this narrow band mode. I do not think you will be able to get to a 0.5 second sweep, which is mostly a hardware design limitation in how fast the device can sweep and sync.
As for the delta marker not reporting delta frequency, this is a bug and not intended. We will get this resolved for the next release. Thank you very much for alerting us to this.
Regards,
A.J.
