Biopowered - vegetable oil and biodiesel forum
General => Chatter => Topic started by: Tony on March 07, 2013, 11:25:02 PM
-
Picked up one of these:
http://www.amazon.co.uk/Samsung-LE40B550A5-Widescreen-Crystal-Freeview/dp/B001UE8LW4
Silly money for a TV, but I managed to get one that won't power on for £19 on the bay of e.
Had it apart and all the PSU caps on the inverter board are fine (darn) but the board had a blown onboard fuse.
Replaced the fuse and it blew again (despite the inverter being disconnected from the rest of the telly).
Buzzed out the PCB and traced it down to one of the FETs that switches the transformer for the cold cathode backlight. Unfortunately the FET has obviously gone into complete melted silicon mode and is a total short circuit, allowing rectified mains down its gate, blowing everything upstream.
So, the inverter board is not repairable, but I think I can get another for £35 or so - so if nothing else is awry should have a rather nice working telly for £54 :)
Now that's some scrounging 8)
-
I'd like a big screen like that as a monitor. I don't think my electronic skills would have allowed me to diagnose the problem like you did though.
-
When I was a teen I used to scrounge TVs from the scrap pile behind the local TV repair company, for them they were "beyond economic repair". But me taking them for free meant they didn't have to pay to have them removed, and I got lots of TVs and VHS decks to play with, from which I learnt a lot.
Most of them would have problems with the big FETs used to switch the flyback transformers, or the transformers themselves breaking down. But the parts could be swapped between sets or replaced with equivalents (this was before the days of easy internet access - had a big book of equivalent transistors).
So I'd fix them up then sell them on, it was useful cash to have as a teenager. Now I'm slightly more mature (not much, admittedly) collecting veg and making something useful from it is not a million miles away :)
-
My 2009 42 inch Samsung LE was less than £2, fixed.
Got some proper rated caps from Maplins but the EEPROM was also damaged which was beyond me.
Anyhow, their PSU faults were endemic and ackowledged by 2011, so they were fixing them free without proof of purchase.
-
My 2009 42 inch Samsung LE was less than £2, fixed.
Got some proper rated caps from Maplins but the EEPROM was also damaged which was beyond me.
Anyhow, their PSU faults were endemic and ackowledged by 2011, so they were fixing them free without proof of purchase.
£2 - I think you beat me on that front! How did you manage to acquire the non-working set?
-
£2 - I think you beat me on that front! How did you manage to acquire the non-working set?
Someone dumped it at the end of my road.
There's a nice patch of grass there so stuff like this just grows overnight.
A few months back it 'grew' a nice 180L copper tank so it was my civic duty to 'pick' it.
-
A few months back it 'grew' a nice 180L copper tank so it was my civic duty to 'pick' it.
That is commendably community minded! :)
-
I know Tony, I know. It's the Oil Drum Lane effect...
http://www.britishclassiccomedy.co.uk/wp-content/uploads/2010/05/steptoe460.jpg
-
Nice work there Tony!
I've just repaired 6x satellite receivers. The same fault on each one - either a dead or dying capacitor on the 3.3V supply. Replaced with parts scrounged from other dead boards and hey presto, they all work!
This is a work related job though, so no real direct gains for me - except some respect from the rest of the crew.
-
I'd like a big screen like that as a monitor. I don't think my electronic skills would have allowed me to diagnose the problem like you did though.
i got me laptop HDMI cabled to a 42inch 8)
-
Me too! And with running XBMC and the vast range of online content available these days I rarely switch it to broadcast.
-
I'll find a big screen at the right price one day.
-
Me too! And with running XBMC and the vast range of online content available these days I rarely switch it to broadcast.
i also got 6 speaker one a bass tube connected for better all round sounds and film experience
;D
-
I'll find a big screen at the right price one day.
asda was doing a 22 inch for 125, im thinking of a 16 they have for the camper as its 12v also... at 89 notes... also well im here asda been doing cheap laptops...
-
Well I replaced the inverter and the TV started and the screen came on - but, sadly, it's damaged in one corner - picture fine but nasty horizontal lines across the top.
There is a screen that might be compatible on eBay but it's quite expensive - I think I might abandon it and sell off the parts (still make a small profit, so nothing lost). Ah well, win some lose some.
-
Well I replaced the inverter and the TV started and the screen came on - but, sadly, it's damaged in one corner - picture fine but nasty horizontal lines across the top.
There is a screen that might be compatible on eBay but it's quite expensive - I think I might abandon it and sell off the parts (still make a small profit, so nothing lost). Ah well, win some lose some.
its all in the journey tony - we are the movers and shakers of this world...
8)
-
My gf has a Samsung 32" LCD, it works perfectly but takes 3 tries of turning it on and off before a picture will appear (the screen always comes on but doesn't show a picture til the 3rd try)
I also have a 42" Samsung that has a thick black band running down the screen. Both out of warranty, think Samsung would repair these free or are don't they qualify?
I've just got back from Australia...they have an interesting way of recycling unwanted goods, they get left outside the pavement outside homes 2 or 3 days before the council are due to collect and the public are free to help themselves to anything they can make use of. And in the more affluent areas the qualify of the goods gets better, if I lived there I reckon I could have furnished a whole house for nothing this way. Lots of metal is left out as well, so it can't be as valuable over there...well they do have all those iron mines so they have a seemingly endless supply at the moment.
Perfect clime for running on veg but I've never seen or heard of anyone doing it in Australia, and new oil is twice the cost of diesel.
-
My gf has a Samsung 32" LCD, it works perfectly but takes 3 tries of turning it on and off before a picture will appear (the screen always comes on but doesn't show a picture til the 3rd try)
I also have a 42" Samsung that has a thick black band running down the screen. Both out of warranty, think Samsung would repair these free or are don't they qualify?
The first case sounds likely.
Find the Uk customer service number and call them, they were very helpful.
If accepted, a local subcontracter will then call you for a time slot to collect it/them.
-
I grabbed two 42" plasmas from the local tip, a NEC and a L.G......
Both have similar but different fault. the 'YSUS' boards and the weird IPM modules they use.....
--Research suggests they are almost Made to go wrong. There is No Need whatsoever the maker Needs to use these modules in any plasma, its just a collection of four or six MOSFETS and drivers for 'em.--They are the only parts you can actually get the schematics of--The IPM modules, but Never the boards they are fitted to!
Only because the Russians reverse engineered them!
(Years ago, it used to be the other way around....) These IPM's fail and often take other devices on the YSUS or ZSUS with them, as in the case of my rescued LG.
--The NEC, I have no idea whats going on. Nothing blown/faulty, all supplies from PSU correct--NO faulty caps----It just dont work.
There is no actual service information or schematics available for either of those makes I have, which makes repairs a problem, the makers (All of 'em) expect you to change the entire faulty board instead of properly repairing the existing ones. The only schematics you'll find for plasmas are of the signalprocessing, and None for the 'panel' driver boards--the main bulk of the device-- (ZSUS, YSUS, Address/X-Boards, Buffer-boards, MPU/Controller boards or PSU units)--So, One board out of 6 to 12 depending on model, you can get the schematics for--The one that rarely breaks down anyway, Aarrgh!!
This is actually deliberate--and we know why. Planned Obsolesence....
That Samaung with the vertical black band will be one of the 'X' boards or 'Address boards' along the bottom of the screen (different makers call 'em different names, but they do the same job)--The one in line with the band....
--Maybe you'll get lucky and it could be a poor connection on the FPB (printed flexible connecting strip)--I seriously doubt the makers will be interested if its out of warranty.
-
Some people fix the tabs detaching from the screen by putting foam packing between the tabs and the frame holding the screen. If the TV is dismantled, squeezing each tab may reveal the one which is causing the problem (picture returns to normal).
Edit: Here we go, a video of someone squeezing the tabs:
http://www.youtube.com/watch?v=XWWayjFU1Jw