Image long tail, brightness control (not dark, can be made of brightness channel, at the end of the class and its power supply circuit fault cause apparent. 8gRservice manual download site
(1) boot, adjustable brightness potentiometer R559, grating brightness is variable, but the tail can't eliminate, trailing more apparent when dim, that failure is not brightness adjustment circuit. 8gRservice manual download site
 8gRservice manual download site
(2) three apparent at the end of the tube collector voltage measurement between 100 ~ 105 v, (normal is 130 ~ 135 v), the voltage is decreased obviously. 8gRservice manual download site
(3) test put level with electric voltage of 130 v (normal is 190 v), the voltage is too low. 190 v rectifier, filter circuit D555, C555 defective. 8gRservice manual download site
(4) under the welding C555 measurements, found that has failed, with 10 u F / 250 v troubleshooting when the new capacitance. 190 v filtering harmful C555 failure, low voltage cut line frequency ripple. 8gRservice manual download site
Voltage reduce to see tube collector voltage is too low, at the end of the tube bundle of current is too large, ABL circuit starts, so brightness potentiometer control effect is not obvious. 8gRservice manual download site
In 190 v line frequency ripple modulation tube cathode, make the image produces long tail like now.8gRservice manual download site