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I have found the only way to make this set
work is to insert three 150 It resistors in series,
between H.T. line and H.T. end of C25 (0.25 pF). If these resistors are removed the PL81 anode gets
red hot and the picture collapses. It seems to be
working O.K. at the moment.
Can you inform me what is wrong ? I have
replaced R34, C25 and C62, also PLSI, PY81,
ECI,80 and EY51. -A. James (S.W.6).
From your remarks we assume that the set only
works with C25 short -circuited since, as you will see from your circuit, the H.T. side of the capacitor is, in any case, connected direct to the H.T.
If this is the case, then the trouble lies in V9
stage, for it is the conduction of this valve which
supplies H.T. to the anode circuit, via the line
output transformer, etc., of the PL81, and if
this is lacking then the screen will glow red hot
and the set will fail to work.

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