I am trying to use a Philips DVD728 with an early-90s Philips TV set that has only a 75 Ohm RF input. I can watch DVDs, after a fashion, by connecting via a mid-90s Philips VCR which has a Scart input. I am also trying to use a Philex SLxRF modulator to avoid the need to route via the VCR. The DVD728 is outputting RGB via Scart using the supplied Scart cable and no trick picture settings. With both options I am experiencing unusual picture problems which I will try to describe. These seem to be related to the relative brightness level of the picture at any time. At low brightness levels the picture starts to 'jump' vertically. It's a bit like the old loss of vertical hold problem but the frame does not unlock completely. When the picture is brighter, it stops jumping, but then another effect comes into play: a periodic brightness/contrast transition with a period of about one second. It's as if someone was switching a colour enhancement function on and off. When the picture is bright, the colours do seem significantly oversaturated. When darker, the contrast seems lacking. It's also worth noting that the picture instability was apparent even in the player's home state, i.e. without a disc playing, which is what leads me to suspect there is an RF modulation problem. I have yet to try connecting the player's composite output via the Philex or the VCR. I note from the player specs that the composite o/p is typically 1V peak to peak whereas the RGB outpupt is 0.7V. I do not know whether this would make a difference. I would be interested to hear from anyone who has witnessed anything similar in the past, and could offer any potential solutions. I am resigned to the fact that I may need to buy a new TV. Thanks for reading!