Dead CRT TV repair: JVC C-212

A dead TV set was brought to my shop for repair. There was no stand by light. Usually that is an indication of a problem either in the fly back and the horizontal transistor in that section or the power section of the TV.
Upon opening and checking the voltages at the high tension area, I found out that there was no voltages reaching the horizontal transistor. I unplugged the TV set and checked the horizontal transistor while on board with a multi meter set to diode setting. The meter gave me a continuous beeps on the three legs. That gave me the indication that the horizontal transistor was shorted. I soldered it out and checked it again. it was D 1555 and was a shorted transistor.
I used the light blub trick which is connecting one wire of the light blub to the collector on board and the other wire to ground and turned the TV on. The light bulb came on and I got a reading of 115 volts at the horizontal transistor. I replaced it with a new one and turned on the TV. It worked for while but I started seeing blue sparks in the TV screen. At first I thought it was a problem with the fly back transformer and I started doing some checking in the high tension area but all the parts there checked Ok.
There was one thing left to do and that is to replace the fly back transformer itself. I looked and searched for one in my electronic junk bile and found a good working one. I installed it and turned the TV on and the same problem happened, blue sparks inside the screen. Conclusion: that was not a fly back problem.

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