Thanks a lot for your help, Tautech, but I'm afraid that either you didn't understand where the problem is or, more likely, I was not clear enough...
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There are two problems here:
1- The NTP server is not reconnecting when I switch (via Utility menu) from WLAN to LAN and then to WLAN back again. My concern was not related to USB thethering with the SDG for Bode plots at all. My problem is that, as I cannot use USB connection with the SDG for the hub/noise issues, I'm forced to use LAN connection to the SDG and thus I need to switch from the usual WLAN operating state of the scope to LAN, preventing the NTP service to run when, once the Bode Plot operation is finished, I try to return to "business as usual" with WLAN engaged. That is where I think there's a possible bug.
2- My USB hub being crappy, which is not the problem I'm asking for, just presented here as
an answer to Pope's request some posts above. The noise problem is not when I'm using Bode Plot but always... the hub induces noise into the scope, although I've just discovered that it is not the only culprit. See later...
I have done what you sugested above and, yes, if I connect the (improved by me but crappy) hub to the back USB port and use it to connect both the SDG connection and the USB memory stick AND connect the WLAN adapter to the front USB port then the noise is gone. Good! but in that position the WLAN adapter fails a lot connecting to the router
I told some posts above that my router is in a different floor. My shop is in the basement and the router is in the first floor albeit just above from where my shop is. Unfortunately I experienced time ago that just plugging the WLAN adapter directly to either the front or back USB ports in the scope yielded to very weak WiFi connection and was continuously losing and regaining connection. As a solution I bought a USB cable extender to put the WLAN adapter in the upper shelf of my shop gaining a lot of WiFi signal. That is, the solution you presented is not valid for me because having an extender USB cable plugged in the front port is not very practical.
BUT... while fiddling with all these configurations I suspected from that very USB extender cable and, know what?... it is also not shielded, as it was the cable from the hub!... again the chinesium curse strikes me back! it is quite possible that buying a good quality USB extender cable will solve the noise problems I'm having
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But stilll there's a possible bug with the NTP implementation in the scope!
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