hi,
I have a samsung pcj 534rfx chassis: p51a
I aquired this as a non working set and I was told by the previos owner that he had to replace a resistor twice and gave up on fixing it when something else blew.
I found the resistor he had replaced, it was the 47 ohm resistor right after the h drive block transformer.
When i powered up the set I got a ticking noise from transformer t802. The first thing I did was replace the convergance ic's because someone told me they were most likely the problem. After that i checked some voltages in the h drive circuit and found 60vac on a 30vac line. I then checked the h.o.t and found no resistance across all 3 legs both polarities I pulled it to check it out of circuit it was the same I have concluded that it is bad, but there is another transistor at q441 that seems to be shorted as well, I have not pulled it to test it out of circuit yet. Am I testing the transistors properly or do the need to be pulled from the circuit to test? Does it seem out of the ordinary that both of these would be bad? Are there any other things I should check before reassembling and powering up? And is there a good way to check the flyback transformer? I believe one of the crt's leaked coolant onto a pcb but I am unsure if that is what is causing the current problems. I am going to install a set of the samsung crt coolant expansion chambers before I reassemble the set. and most likely a fan pulling air out of the vents on the convergence board side of the tv. is there any other parts that I should check that may have contributed to this failure?
Any help would be appreciated.
just a follow up, the transistor in position q441 also read bad when I pulled It.
I am still looking for bad parts in the power board but if there is anyone who has experienced a simialar problem or can give me some pointers please feel free to chime in.
Thanks,
Kyle
Do you have a schematic or a service manual on this set? If you do not then you can get the original from HERE The convergence IC's as well as the horizontal output transistor and the flyback transformer is a very common fault with this model number. It is a hard call though without looking at the TV set. Good Luck and if you have little TV service experience, please call in a pro to assist you in this repair.
hi larry,
Thanks for the link for the manual but I already have one.
i paid more though
I have already soldered in both new covergance ic chips, and as soon as usps brings them I am going to put in both of the bad transistors i found. I have removed all the transformers off of the power board including the flyback so that I can clean the areas affected by the coolant leak without filling them up with water and ammonia.
Is there a effective way to test the flyback while it is out with a dmm or is a fail under load thing?
Not without a coil or transformer ringer. HERE is a good place to start to test a flyback or LOPT