# Solved: TV Repair



## gurutech

I recently got a good deal on a Hitachi 60" TV from Craigslist. I bought it "as-is", and I know that it didn't turn on before I bought it ($100 for a $4000 TV is a good deal!!!).

I took the back panel off already and found about an inch of dust inside, so I vacuumed it all out, and still nothing. The model # of the TV is a 60SBX78B. I've looked online and found that the problem may be the power supply, and to have it repaired may cost me an extra $400. (which still makes the TV worth the money, I just can't afford the price right now. 

Anyone know where I can get a replacement power supply for a decent price (maybe $100 or so??) Or even how to replace a power supply (what to test for and how, not necessarily the process for removing it and such).


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## kiwiguy

You are into specialist territory here, as the fault could be deeply embedded in the set, which may only look like the power supply failure at this stage.

Without the service manual and correct test gear (and the most important bit, the experience) you could (you usually will) spend many times the cost of a professional service call.

I have seen the posts on-line that you refer to, but you make a large leap of faith to apply any certainty that it is "just the power supply".

I am fully certified in TV repair, but non-practising and have no experience with that exact model in making the above claim .... my comments are based on the generic likelihood only.


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## JohnWill

I have to agree with kiwiguy here, there's no real way of knowing what you have. I think the only serious option would be to take it to a shop and get an estimate of what's really wrong with it.


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## gurutech

Take it to a shop... HA HA HA - that's funny! You try taking a 60" TV to a shop!

Would be cheaper to have them come out to my house!


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## kiwiguy

The problem is (worst case), if the fault lies beyond the power supply, then it will force the supply into "protection mode", which can look the same to the untrained tech as a failed power supply, meaning you shell out for a module that you do not need, only to find the fault so deeply embedded (e.g. due to severe power surge) that it has taken out all the deflection and audio circuitry etc, making repair exceptionally expensive.

And when you decide that it's not worth repair, you are left with an expensive power supply module.

The sets these days are microprocessor controlled, a failure in one area causes protection to operate elsewhere.


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## gurutech

Well, here's what I've been able to find out so far (looking at it myself):

1. It hasn't blown up yet.
2. There are several "jumpers" that go from the power supply board to the board with all of the "video in" type connections, and powering on the TV with all of those jumpers not connected results in 3 green lights staying on.
3. Connecting the jumpers from above will cause 3 green lights to come on for a few seconds, then a few more green lights come on, then they all fizzle out.
4. Connecting the jumpers one at a time pinpoints it to the 3rd jumper.
5. Something's telling me it's not a power supply anymore, as I can unplug that 3rd jumper and it will stay "on" indefinitely, but still won't power on.

Needless to say, I will be calling a few repair shops to see if they offer on-site repair, and how much it would cost.

This is a rear projection TV, not sure if they are all the same, but if you have experience with one, I would ***-u-me this one souldn't be too hard to figure out... I've done component level repair on computer monitors before. Just nothing with 3 cables coming out of the flyback transformer before! lol


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## telecom69

I was interested in this as I used to be a bit of a dabbler myself,you have to be realistic and think that this tv has been checked out at source,as regards getting it repaired,and found perhaps that it might well cost a small fortune,this is the problem with sets of this size and price range of course,In my opinion its no good whatsoever in trying out a substitution repair,it needs expert diagnosis thats for sure,as the fault could be absolutely anywhere ....I did however find this below offered as a solution to try,you never know....

Followup To 
Question - 
My projection television is a Hitachi Ultravision, model number 60SBX78B and was manufactured in Oct. 1998. It was working great last night, but tonight when I went to turn it on, nothing happened at all. So I unplugged it for a second and plugged it back in and then pushed "power" and it came on for about 3 seconds, then turned itself off. I have unplugged the BOSE sound system and the cable box both from the Hitachi, so I unplugged it and plugged it back in the second time now only to get the exact same result again. Is this anything I can fix on my own? What is wrong and what do you suggest? This is the first and only problem this t.v. has ever had since I bought it new in 1999. Thank you very much.
Answer - 
This is usually, not always, the worst kind of news one can get. The protection circuit has detected a shorted down condition somewhere and shut the ON relay OFF.

The problem is there is no way to know for sure what the defect is without a diagnosis. All we know is the protection circuit has detected excessive current from somewhere (could be anywhere) in the set. 

So, you must have a qualified tech come to the set and open it up and check it out. 

The problem could be an easy one or not. A common failure is the high voltage system or the deflection systems.

You can try a hard reset and the whacking test, but ultimately you will need a technician to make the repair. Consider it one of the burdens of owning a big screen set!

HARD RESET: Unplug the power cord for 4 hours or overnight. If this does not help, then the problem is hardware failures and not software corruptions.

WHACK: Just smack the cabinet with your hand or fist in several locations. This will wake up any loose connection or cold solder joints that may have gone to sleep. Worth a try.


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## Knotbored

It seems to me older TV's had a warning lable about high voltage being maintained even after it was unplugged, something about condensers and dying young. I won't stick my hand in there.


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## JohnWill

gurutech said:


> Take it to a shop... HA HA HA - that's funny! You try taking a 60" TV to a shop!
> 
> Would be cheaper to have them come out to my house!


You somehow got it to your house, right?


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## gurutech

Yeah, got it in the house, and it's gonna stay there! If I had a single story house, it would be no problem, but getting this beast down the stairs without it falling on me was a feat in itself...


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## JohnWill

I was thinking if you got it outside the house, you could use it on your boat for an anchor.


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## gurutech

Or I could take the back panel off, and use it AS my boat.... lol


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## JohnWill

There you go, yet another reason to take it out of the house.


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## gurutech

When it rains hard enough, I can load my "boat" with all my PC equipment to keep it dry....


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## mosha23

i have a 6 year old philips tube tv, and some times the width of the screen will shrink and the length will increase, and when i go to change the channel or change the volume or anything. there is like a delay, would you know what the problem might be. thank you.


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## silentmage

Knotbored said:


> It seems to me older TV's had a warning lable about high voltage being maintained even after it was unplugged, something about condensers and dying young. I won't stick my hand in there.


it could be a bit shocking. i used to take apart tv's to see how they worked (btw, dont mess with the tuners beind the tube, bad for the picture) and have gotten quite a few jolts, not fun... after the first few times that is.


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## john1

https://merchant.satisfusion.com/sf...odelOID=SF-990180694-220&random=1194719118921


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## john1

looking through their manual downloaded from the link above,
i found this useful hint about an apparent loss of power, on page 56.

I feel a workshop manual would be more useful.

John


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## teknofix

I am a new bee here, trying to post.. I have also *HITACHI CT7872B* 27'' TV Dead ! On initial turn-on power relay engages and high voltage tries to come on for a second but nothing happens..No screen or sound. Just
relay clicks on/off with power button on/off. any thoughts or sugessions
how to troubleshoot this problem..? Thanks..


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## gurutech

For a 27" TV, it may be cheaper to replace the TV. Especially if it's a "tube" TV.


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## teknofix

Thanks for your help, if I wanted to do that, why would I seek for opinion..>?


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## gurutech

If you want to repair it, start with the power supply and the flyback transformer (the thing that has the big red wire coming off of it running to the top of the tube.) Doesn't sound like it's generating enough power for everything to power up, and is shutting down again.

Power supplies can run around $100 or so,, and the flyback transformers are around $50. Plus installation, that could run you more than a new TV.

That's why I suggested the new TV the first time.


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## teknofix

PSU voltages checks ok. I have replaced the power IC : UPC1394C now I can hear the high pitch, means Hi-Voltages trying to come up, but still no raster and filaments are not on at the neck of the CRT. Voltages arround the IC checks arround -60V ! which is not right, looks like a missing ground caused by open component somewhere which I wasn't able to locate yet, since everything checks ok..I am suspecting bad (partially open) FBT and trying to find the part #.. Thanks for your reply, appreciated..


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## gurutech

Definately the FBT at this point... Try resoldering the connections on the board. Sometimes a cold-solder joint will cause the high screeching noise....


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## stellarspy

Hey teknofix, Did you get your tv working yet?


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## teknofix

yes. thnx.


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