I have been given a dead Liteon DD-A100X DVD recorder and would like some advice about repairing the power supply.
On inspection, the wire ended mains fuse, FS1 (T2A 250v) was blown. There was a black flash mark on the PCB between the chopper transformer, T1 and transistor Q3 (P4NK60ZFP). I have found what appears to be a fusible resistor of 1 or 2W connected to Q3 and the neutral side of the HT capacitor Ck1 (47uF). This measures open circuit and the reference number on the board is not clear, but maybe Ra1. The colour code of this resistor is violet, green, silver, gold, green, which would indicate a very odd value of 0.75 ohms. Can anyone please confirm the value of this resistor. Surprisingly, no short was measured across the terminals of Q3.
I am inclined to replace Q3, the optocoupler PH1 (CX 817C) and the 47uF 25v electrolytic at the side of this and resolder the joints around T1 as they don't look very sound.
Any further advice would be greatly appreciated, particularly with the value of the safety resistor and possible a circuit diagram of the power supply.