Some good news.
I got the AC adaptor recommended by Thierry Henry and it works great. Unit is now displaying all games crisp and clean on my HD TV.
I recommend anyone needing to get a PC Engine to invest in this type of AC adaptor to moderate the voltage.
Mine came with a UK three pin plug but a simple travel adaptor got it running here in Asia.
Now the next question. The picture is lovely but how can I get my system running with stereo sound as the cable that came with it only has a basic two lead AV output and I can hear that the sounds aren't perfect on Dragon Spirit in comparison to the VC version I was used to.