Hi all
Mastercare engineer arrived on schedule this afternoon..................
He checked the set and was able to see the dirty screen issue I reported, mind you it was tad embarrasing at first as it is now so faint I could not initially find it myself to show him ! (showed up most with Touching The Void Dvd during a few of its snow and blue sky scenes).
He stated that he had no fix for this and that it was a problem with all 36" CRTs (he said Toshiba sets were best in this regard though) as the technology is really pushing it limits with such sized screeens. He said the dirty screen is down to minor manufacuturing flaws in the Shadow Mask of the tube (hence no fix) but these flaws were within permissable limits (his words not mine).
Whilst offering a fresh set without hesisatation (in his words it was "no skin of his nose" to order one) he stated that there was no guarantee that a new set would be free of the issue (to be sure he reccomended getting a 32" version).
I asked if it was likely to get better or worse and basically he said there was no way of telling.
He did reccomend keeping the TVs Contrast at 75 or below and that a least once a week the set should be disconnected from mains for several hours (eg overnight) so that when re-connected the deguass was purer. This was advice I have read on this forum as well (and indeed have been switching off overnight so it may be factor in the improvement of this dirt for me ?)
No mention of made deguassing wand.
As I am no expert myself I had impression that he was at least truthful and genuine but no way to gauge his knowledge base.
So upshot is that I can get a new set if I wish (and issue was left that that option was still open to me if the fault got worse again or I changed my mind)but I have decided to stick with my current set in meantime as it has most definately improved to point were I no longer notice the dirt except on a very few occassions and its other PQ strengths are enough for me to keep it.
In back of my mind with these 36" sets (of whatever brand) is that getting another may produce a worse or different fault as it seems from reading forum that its a bit of pot luck regarding quality.
A 32" set would now seem a tad pokey (as they say locally

).
One can only hope the fault does not get worse again.............
Cheers