Jean-Pierre, it worked. Great. Now for an unknown reason I cannot reason VLC cannot read the stream udp://188.8.131.52:10001. OBS can. Sometimes. DB0HEX (rtsp://184.108.40.206:2555/axis-media/media.amp) works. But not in OBS. Sometimes. It's confusing.
I've Win10 20H2. After this update, some things are different as they were before.
A computer connected to the internet has to be up to date. But I hate the trouble you often have after updates.
OK. I found the vlc problem. After reinstalling 32&64bit VLC all my network "presets" were erased. For an unknown reason vlc needs an @ in the command line: udp://@220.127.116.11:10001. This is different to OBS and confused me.