Re: Pye v4
Peter I would be interested in your suggestions as where to look as on two ocassions you have been spot on so please offer any advice.
I don't want to incurr the wrath of John & Trevor, as they will go nuts when they find out that the line setup still has not be done and might be the route of this issue and I have not figured out the sync decoup cap (although I think I have changed it)
I have switched on and observed the following:-
Test card appears but is squshed and quite dark, as the set warms up the test card expands and becomes brighter and the vertical/horizontal lines are straight, the centre circle is squashed. Eventually the test card just about fills the screen and is resolved nicely. Then the definition decreases and it looks slightly smeared as if capacitance has been added to video circuit as described in fig 172 page 26 of Sreadbury, although not as severe.
This all takes place within 8mins
pictures 1-5 show the progression.
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