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Fallen TV - no picture, sound OK

Hi all, I tried posting this back in my original thread, but I can't for some reason (maybe it's too old or something), which is why I'm pasting the original message in here, along with my follow up question. Hope this isn't a horrible breach of usenetiquette...

> > > > > Hi all, I've searched around this group a bit so I think I've an idea > > > where my problem may lie, but I thought I should ask anyway, just to > > > make sure. > > > TheTV in question is a Beko 284222WNS. At a recent party in my house, > > > it was knocked off its table and landed on its screen. The weight of > > > it ripped the plug out of the wall socket (and broke off the "Earth" > > > pin, which was actually just a piece of plastic moulded to the plug). > > > Amazingly it didn't shatter, and from a brief look inside, nothing > > > seems to be broken or dislodged (it's a wee bit too heavy to pick it > > > up and shake it to see if anything rattles). > > > When I powered it up, the picture was gone completely, but the sound > > > seems to be OK. I can't feel any static from the screen on power-up so > > > I guess I've got no high voltage. Does this mean a transformer is > > > busted or could it be something else? > > > Any advice would be very helpful, I'm just wondering really if it's > > > worth my while taking it in to be repaired... > > > Cheers, > > > Anthony > > > Maybe you need to read the F.A.Q. for the newsgroup before you post: > > >
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> > Thanks, I hadn't seen that, sorry. And thanks for all the tips > everyone else.

(and now the follow up):

I know it's been many months since I last posted on this, but I just thought I'd check with you guys one last time before consigning this TV to the dump. Having read all your posts, and the FAQ, I looked around the board for any cracks, and lo and behold, there was quite a sizeable one running close to what I assume is the flyback transformer. And sure enough it was running right through a fairly big track. So I fixed the crack, then ran some solder and a thin wire along the broken track. I checked it with my multimeter to make sure I had a good connection between either end. The thing is, it's still not working, and I noticed that one of the smaller components near the transformer looks a little burnt (or at least brown - could just be flux i suppose) on the underside (I'll have to check again later which part it was - I can't find the piece of paper that I had written it down on right now), and I guess it could be that, or else maybe the transformer itself is just f***ed. If that's the case is it worth my while trying to fix it at all (bearing in mind that while I do know how to solder and read circuit, I don't really know what's going on on that particular board :)). I've already gotten a replacement, but I figured if this one would be an easy fix I'd keep it for the spare room, but if not, then so be it... Thanks again for all your patience.

Ant

Reply to
Tony Ramone
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I have worked on dropped tvs many times. as others here have said, chances are you have more cracks. i've been caught out like that before.

Also, I have had the pcb flex on landing and some transistors and regulators worked loose from their solder pads. That was on a Hitachi

28" widescreen set. look for heavier components , transformers, heatsinked stuff. BTW I think the brown component you mention may be a red herring. I'd look elsewhere first and come back to that later.

check the pcb on the tube also, in case.

keep at it

-b

Reply to
b

On Thu, 5 Mar 2009 14:03:54 -0800 (PST), b put finger to keyboard and composed:

I'd also drill a hole at the ends of each track, components and traces permitting. This will relieve any stress and prevent cracks from propagating.

- Franc Zabkar

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Please remove one \'i\' from my address when replying by email.
Reply to
Franc Zabkar

Novel concept. While this may be good practice on a single material PCBs are composites, and it's usually just the track that cracks. And by nature tends to be across the entire track so can't spread anymore.

--
*Time is what keeps everything from happening at once.

    Dave Plowman        dave@davenoise.co.uk           London SW
                  To e-mail, change noise into sound.
Reply to
Dave Plowman (News)

On Fri, 06 Mar 2009 07:29:20 +0000 (GMT), "Dave Plowman (News)" put finger to keyboard and composed:

Sorry, I should have written, "drill a hole at the ends of each crack", not track. My former boss always insisted on this.

- Franc Zabkar

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Please remove one \'i\' from my address when replying by email.
Reply to
Franc Zabkar

Ha, the drummer in my band does the same thing to cracked cymbals. It works though. Thanks for all the new tips guys. Hopefully I'll get to have another look at it this weekend.

Reply to
Tony Ramone

OK, so I finally had a chance to have one last look at it a couple of weekes ago before deciding to throw it out and, sure enough, there were a few more cracks that I hadn't seen the first time round (the lighting in the room it was in is fairly bad). So I got out my tools again, patched it up, plugged it in, stood back and, with a long stick in hand (maybe overly cautious :)), switched it on. Badda-bing, badda-boom - I've got a picture. So I'd just like to say thanks to everyone here for all the helpful tips, it's much appreciated. Cheers, ANT

Reply to
Tony Ramone

well done -persistence usually pays off with these things!

-B

Reply to
b

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