This machine for discharging high voltage circuit type highlights. When you shut down, by the accelerating voltage filter capacitance C870 store voltage to accelerate anode high voltage discharge, eliminate the shutdown highlights.

So the shutdown highlights may be generated by the C870 fail. In addition, brightness, brightness not clamped properly, but also eliminate the effects of the shutdown highlights.
(Repair)
(1) using a 2000pF/2kV capacitor parallel to the C870, observe the shutdown highlights, the results did not change, the C870 is good.
(2) 100pF/16V capacitance parallel connection at C305, observe the highlights, results highlight the total elimination. Shows blanking pulse clamp capacitor failure, IC501 14 pin voltage do not remain after shutdown. 14 foot is inversely proportional to voltage to the CRT cathode voltage, thus reducing shutdown current Imaging bundles, anode high-pressure relief well, shutdown highlights.
C305 100 μ F/16V machine is returned to normal.