If STR is found damaged, you should check all the assciated components with it; like resistors, zener diodes etc: before replacing a new STR. All such components should be checked individually [out from the circuit
]. Check and replace damaged component/s at its horizontal scan output section circuit. Check the LOT (Line Output Transformer) too for damage. Replace the horizontal scan output transistor. Check the input voltage to LOT. If the voltage is absent check the feeder resistor; if any. If you wish to get some details; check the site linked here. Pull up older posts.
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