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#1
09-09-2015, 07:56 PM
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Sony color KV1354R shorted horizontal output
Working on a 13 inch Sony, which is dead except relay clicks. Shorted Horizontal output transistor D1396, ECG2302. I assume the flyback shorted the transistor which is a Sony 1-439-314-11. (flyback shows no signs of overheating, cracks, or smells) Also wondering if it took out the regulator/audio IC STK563F ECG 1732 Anyone ever just change out the transistor and have some luck with it powering up? I know most of these sets are throwaways, however it had a perfect picture before going out, and the set is super clean inside and out. I know most of the parts are available through e-bay, but reluctant to spend money on it. If it were just the transistor, it wouldn't be so bad. Any thoughts?
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#2
09-09-2015, 08:18 PM
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Quote:
No Horiz drive - bad solder at the driver transformer, bad driver transistor, open resistor in drive ckt. Shorted fly - pull it and ring it if you have a ringer (we used a VA62) or a HR machine. Short in one of the scan derived supplies - secondary, lower voltage supplies off the flyback -open caps lead to shorted rectifiers, which leads to HO failure. Other odd problem - mishapen drive pulse, poor B+ regulator, no regulator feedback, bad shutdown circuitry, or something else.
__________________
Brian USN RET 22YRS (Avionics/Cal) CET-Consumer Repair and Avionics ('88) "Capacitor Cosmetologist since '79" When fuses go to work, they quit!
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#3
09-09-2015, 10:52 PM
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It could have very well taken out the regulator. About 20 years ago, I was given a 19" Sony from the same time period as yours and it had a shorted HOT. I didn't want to fool with it and I gave it to a friend. He found that the flyback was what took out the HOT and after replacing the flyback and HOT, the set went into shutdown; but, would stay on at lower line voltage. He determined that the combination audio output/voltage regulator IC was bad.
Out of all the sets that I've serviced (all brands), I've found these parts to be common failures. Sometimes, a HOT will blow on it's own; but, more times than not, something caused it to blow and based on my experience, I'd look at the flyback as being the cause. When replacing the parts, try to stay away from NTE parts and go with the original part numbers, if you can find them.
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http://www.youtube.com/user/radiotvphononut
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#4
09-10-2015, 07:54 AM
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Pretty sure if it has the big audio / regulator IC the
H out didnt blow. Most the audio failed with crackling. Also they loved to get cold joints. The FBT was usually the culprit. Also look at the little disc caps going E-C of the HOT. IIRC this had the 220pf that shorted often. Story. I think it was this model. Set came in, bad HOT, FBT, fuse. Customer said to junk it so I put the chassis in our junk yard. Another came in a few days later same problems. Put that chassis on top of the other & happened to look at the serial tags. CONSECUTIVE !! Called both customers. They both got there sets at Lechmeres on xmas eve.......... Both ran abt 15 yrs without service & died within days of each other. Maybe they do put timers in them. 73 Zeno 
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#6
09-10-2015, 06:30 PM
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Man.. I wouldn't be surprised about that built in timer. lol
The set Walter is looking at is mine. I've only had it a few weeks, so go figure it would die 2 hours after I brought it home. Got it at an estate sale.... set was in a spare room ... only hooked to the rabbit ears and plugged in. Fired it up at the sale, saw snow, bought it... brought it home, and after playing 2 hours, dead. Set had a PERFECT picture before she died.....
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