+- Gold Coast CB (https://goldcoastcb.stream)
+-- Forum: BOARDS (https://goldcoastcb.stream/forumdisplay.php?fid=3)
+--- Forum: PROJECT AREA (https://goldcoastcb.stream/forumdisplay.php?fid=6)
+--- Thread: PROJECT: HOW TO FIX AN LCD TV FOR LESS THAN $5 (/showthread.php?tid=67)
Re: PROJECT: HOW TO FIX AN LCD TV FOR LESS THAN $5 - Thunderbird - 05-11-2012
11.5 volts on the 12 volt rail is probably ok. Is there anything else hanging off the 24 volt rail on the PSU end? Did you check the 24 volt output at the power supply? If the power supply isnt putting out 24 volts, I'd be looking for a fuse, it might not look 'fuse' like, but will probably be marked F1 or F2 etc on the board. Next up, check the diode on the 24 volt rail on the psu see if its shorted or open. Cant think of anything else atm, but if ya dont get it going in the next coupla days, Ill bring over some special goodies to test it with.
I have some spare inverters as well.
Re: PROJECT: HOW TO FIX AN LCD TV FOR LESS THAN $5 - cOOter - 05-11-2012
(05-11-2012, 08:28 PM)Thunderbird link Wrote: 11.5 volts on the 12 volt rail is probably ok. Is there anything else hanging off the 24 volt rail on the PSU end? Did you check the 24 volt output at the power supply? If the power supply isnt putting out 24 volts, I'd be looking for a fuse, it might not look 'fuse' like, but will probably be marked F1 or F2 etc on the board. Next up, check the diode on the 24 volt rail on the psu see if its shorted or open. Cant think of anything else atm, but if ya dont get it going in the next coupla days, Ill bring over some special goodies to test it with.
I have some spare inverters as well.
Special goodies are good
The fuse at the 240v in is good.
The second fuse in the center of the board is good. TV wont start without it.
All cables have been unplugged and replugged to make sure connections are jiggy.
I'm out of the shed now (bloody mozzies) otherwise I'd pull the power board back off and have another look at the solder joints on the boards under side.
Samsung LCD backlight fix.
I had it off today and noticed similar shaped solder joints like the one shown in the above video. (I hadn't seen this video then)
I'll do an update tomorrow. Cheers
Re: PROJECT: HOW TO FIX AN LCD TV FOR LESS THAN $5 - cOOter - 06-11-2012
Update: Nah, soldering the joints didnt work either.
Still no power from the PCB to the bottom of the backlight inverter.
If I knew for sure it's the faut of the inverter, I'd just replace it, but if it's the PCB, then it's pointless buying an inverter.
I'll have to see if Chopper can fit me in for a service.
Re: PROJECT: HOW TO FIX AN LCD TV FOR LESS THAN $5 - cOOter - 19-11-2012
UPDATE: The thing has been sitting in the shed pulled apart all week.
I was about to order a new back light inverter for $55 delivered from the US, but I thought, have one more looksie cOOter.
It helps to make sure all 16x back light CCLF tubes are in their socket holders.
If only one is disconnected, none will fire up.
Tube #5 wasn't in it's holder, thus the high reading on #5 the other day.
Yeap, so I pulled transformers off the back light inventor board for no reason.
OK, it's working now - I guess my re-soldering passed.
Chopper was a great help as well going over everything with his yoyo. No broken strings
It still might be a bit dicky on cold starts with a slight blink.
Brother Darren was using a power drill in the shed behind me today, and the 200 watt TV would go blank as if the PCB wasn't getting enough power. (we share the same 240v 10amp extension lead from the house 20 meters away)
Not sure about that yet.
Now it's back down stairs on the test bed. (oldies living room TV stand)
Re: PROJECT: HOW TO FIX AN LCD TV FOR LESS THAN $5 - Thunderbird - 19-11-2012
Good to hear that its working once again. I have no luck finding a service manual or circuit. Only other thing I can think of is to try each tube out with a CCFL tester, an old laptop inverter might do the trick, and I have seen someone use the base of one of those compact flouros as a tester, pretty dangerous though, just how we like it
Re: PROJECT: HOW TO FIX AN LCD TV FOR LESS THAN $5 - cOOter - 19-11-2012
Just brought home another one. LA40R71BD
Screen is rooted, no stand, but being 40" I might be able to salvage some tubes for spares and flog some bits off on eBay.
Re: PROJECT: HOW TO FIX AN LCD TV FOR LESS THAN $5 - Thunderbird - 19-11-2012
Cool, yep Ive swapped the tubes out from one to another, they seem much the same as long as they physically fit, in fact Ive grafted a 17 inch one into a little 15 inch hd tellie in the skunkworks, it pokes out the sides a bit...
Re: PROJECT: HOW TO FIX AN LCD TV FOR LESS THAN $5 - cOOter - 22-11-2012
(19-11-2012, 07:52 PM)Thunderbird link Wrote: Cool, yep Ive swapped the tubes out from one to another, they seem much the same as long as they physically fit, in fact Ive grafted a 17 inch one into a little 15 inch hd tellie in the skunkworks, it pokes out the sides a bit...
Marget that
The color produced varies in some as well.The other TV is still working now after a few days of use. I must'a fucked up somewhere for it to be working
Re: PROJECT: HOW TO FIX AN LCD TV FOR LESS THAN $5 - Thunderbird - 22-11-2012
Well done, Im pleased to hear it. Gotta keep those goodies out of landfill. Keep the bits out of the buggered one though
Re: PROJECT: HOW TO FIX AN LCD TV FOR LESS THAN $5 - cOOter - 22-11-2012
Shit yeah. 40" CCFL tubes sell for $19+ each. Not that I'm gonna sell 'em, but they can be used in other 40" sets.
Still poking through the PDF books ya sent. Could be a good side line as more units start going bad.
Now with LED units it should all be easier in the coming years.
Although I'm guessing LED backlight units will be more robust to knocks and drops by drunks.
