Pre-war Baird TV receivers employed extended frame timebase transformer pole pieces.
Link to the CRT replacement topic in my Baird T23. Post No.33 shows the transformer and it's extended pole pieces.
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https://www.vintage-radio.net/forum/...d.php?t=132064
Unsure if it was Baird Television Ltd or Fernseh AG that had developed this type of timebase generator.
DFWB.