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EKCO T283
Two vertical bars of light divide the screen- which lacks illumination-into three sections.
There seems to be insufficient e.h.t. at the anode
of the U25.
I have replaced the 30P4 and substituted the line oscillator valve without tracing the fault-G.
Laidlan (Shildon, Co. Durham).
These symptoms are caused either by a faulty U191 or to a faulty boost capacitor. This is the 0.5uF component below the chassis near the line output transformer vent hole.