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Jeroni Paul

hr(bob) :
Is the degaussing circuit working. IF you are not sure, get hold of a
degausssing coil and manually degauss the CRT. You don't say if this
is a new problem or was that waay from the beginning, and what might
have happened such as dropping the set, or unplugging a vacuum cleaner
right next to the set, or whatever. These are im[portant clues.

I have checked the degaussing coils operate correctly as playing with
magnets I've magnetized the CRT and a cold degauss restored it. They
also make a very audible noise.

Have been playing with some magnets around the tube and found that
placing a small magnet at the right orientation around the deflection
coils next to the tube gets rid of the purity problem. Two magnets,
one per discoloration, I can get it perfect.

However I wonder if that is the solution to the problem or should I
look elsewhere for something misaligned. The yoke appears firmly
attached to the tube without signs of having moved, it is glued there.
The convergence / purity rings are intact with their original painting
as well as some adjustment screws around the coils.

I have noticed there are three windings electronically controlled,
probably used for rotation. One next to the convergence / purity
rings, one around the deflection coils next to the tube and one around
the entire tube together with degaussing coils. What do these do?
Could a failure of one of these cause the problem (I mean the
electronics that control them)?