"Geoff"

Left side of trace has a ripple, about 1/2 division vert
amplitude and about 25% of horizontal is affected.
Both channels the same
When vert offset is manually swept, the pattern of ripple
changes, still both channels the same
Timebase does not change shape or size of ripple
ripple is 1/2 or 1 cycle but is like someone has put a magnet on
the side of the tube.


** Could the case be magnetised in one area ?




.... Phil