If I plug it using the SCART cable, it's OK, but if I use an UBESWITCH (Mark VI) or an ST2VGA from Exxos store, I can get a picture to display.
The Medusa display an ever fluctuating value for sync signals but doesn't sync. Moreover, I realized the HSYNC frequency displayed is twice the right value (like 31khz for low res..).
Everything works fine using the same setup with an OSSC instead of a Medusa.
So I tried to have a look tonight, scoping the VGA port and I can't see any obvious fault anywhere.
Here are 2 screenshots, first one from a standard 520 STF which works perfectly fine with the Medusa and second one from the H5.
The 520 STF
The H5
At least the scope shows that the sync values are good.(I triggered on VSYNC and a second time on HSYNC).
Measurement is done on the VGA connector at the output of the UBESWITCH.
Obviously I could use the H5 with a VGA connector directly instead of the DIN13 and use the internal jumper to switch Low/Mono resolution and it might work, and I might try that in the coming days, but it also means drilling the case to access the audio jack
Or I could keep using the OSSC, but I must admit the picture quality of the Medusa is vastly superior to what I got after hours of tuning all the parameters of the OSSC.

