Re: Bush Dual Standard Colour Restoration
The convergence problem was an o/c 50 mfd electrolytic which couples the frame output pulses to the convergence board. Scoping the sync input to the timebase board shows that it is of the right amplitude but has a lot of video content on it. This no doubt accounts Glyn for the wavy verticals and poor frame sync.
Now that the picture is decently converged, poor low frequency response with smearing is apparent, some of it coloured (see attached). The definition is otherwise excellent so I don't suspect a tricky IF problem, but rather couplers/decouplers throughout the signal stages. Rather than fault find I will now just go through the signal panels replacing all the horrible red TCC electrolytics and take it from there. I haven't finished on the convergence set -up as yet but it's more than good enough at present
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