Re: A scary Baird T23.
Before I become brave again and remove and refit the CRT it's time to take a look at the frame timebase. The picture is off-set to the bottom of the screen.
The single valve timebase employs an oscillator transformer which also performs the vertical scanning by means of those extended pole pieces.
The DC current through the transformer primary is cancelled out by a third winding, see the attached circuit diagram. Earlier this evening the timebase unit was removed in order to find the picture shift fault. Well it turns out that the picture shift winding has been disconnected. Later on I'll reconnect the winding and report back the results.
DFWB.
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