Happy scrounging - 40" Samsung TV in progress

[Tony]

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

[greasemonkey]

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.

[Tony]

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

[Glycer-rides]

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.

[Tony]

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?

[Glycer-rides]

£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.

[Tony]

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!

[Glycer-rides]

I know Tony, I know. It's the Oil Drum Lane effect...
http://www.britishclassiccomedy.co.uk/wp-content/uploads/2010/05/steptoe460.jpg

[therecklessengineer]

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.

[Rotary-Motion]

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 

[therecklessengineer]

Me too! And with running XBMC and the vast range of online content available these days I rarely switch it to broadcast.

[greasemonkey]

I'll find a big screen at the right price one day.

[Rotary-Motion]

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

 

[Rotary-Motion]

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...

[Tony]

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.