Equpment:
Input: Jap megadrive & Jap Super famicom.
Cables (from retrogamingcables)
Female RGBS SCART to BNC adapter breakout cable for Sony PVM and BVM monitor (£12.99 one NOT the £30 with sync seperator)
Snes Ntsc Rgb cable with csync
Megadrive RGB SCART csync
Problem
Lots of small (diagonally skewed) versions of the picture scrolling. I.e No sync.
Fix that worked for me:
Tried [menu], [setup], [input config..], changed setting to 4:3 underscan in the menu, (it didn't work) then switched to 4:3 and changed "safe area" to to "off" and scale to "4:3-100" and the picture just snapped into perfection!
Additional Info:
Basically stumbled on the solution by fiddling around with enough settings in the input configuration menu. I read a few other people had similar fixes by switching back and forth between different settings in the "format" and "sync mode" submenu. This can trigger the monitor to sync in some cases.
Stuff that didn't work 100%:
Tried switching to internal sync (button on the control panel of the monitor). It didn't work but did have a different timing to the "broken-ness".
Tried: [menu], [setup], [extend menu, try password 0000, 1111, or 9999)], re-load factory data. I think this is facory reset but on mine I could only access 3 of the 9 "slots". so I reset them in the following order: slot 2: SDI 4.2.2/4FSC, slot 6 VIDEO AMP, Slot 7: Deflection. All the other slots were greyed out and I couldn't access them (maybe because I didn't have anything plugged into the physical pcmcia slot on the front of the control box. It acted like it reset but my (self-created) channel presets were still there so did this do nothing? If anyone knows please reply.
I also tried what one guy on here tried: Plug sync into Green OUTPUT. It actually did work and I understand sync on green but it just felt wrong (plugging an input into an output (or daisy chain) port. Is there a setting to turn off "sync on green" somewhere in the menu for the BVM-20F1U? I couldn't find it.
Anyways hope this helps someone.