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[email protected] PlainBill@yawhoo.com is offline
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Default Wanted CCFL tube for 22 inch widescreen LCD

On Thu, 20 Oct 2011 18:11:01 +0100, Clyde
wrote:

On 20/10/2011 08:22, N_Cook wrote:
wrote in message
...
Hi, fixing this for a friend. TV is a cheapo Argos (Wharfedale) 22 inch
widescreen. One of the backlights has failed, causing the inverter to
shut off after a few seconds. Confirmed failed lamp using a spare CCFL
tube I have laying around. LCD panel (Samsung) has 4 tubes, 2 at the
bottom and 2 at the top. Tube measures 480mm end to end. Wires are very
closely soldered to the tube ends. Has anyone got any laying around,
perhaps on a broken screen? Or where would be a good place to get one (UK)

I can pick one up online, but they seem to have longer ends for the wire
connections, so we would probably have to get one with wires presoldered
on, or go for one slightly shorter.

Getting the panel apart to gain access to the tubes was fun, I expect
even more fun putting it back together and trying to keep it clean.
Probably not really designed to be opened up, but the LCD itself is good.



How many inverters for the 4 tubes? I hope you marked the orientation of the
diffuser sheets before removing. Is the failed one visibly different , ie
blacking? Does it try striking but pink?


Hi, the failed lamp is visibly darker on the end and does not strike at
all. The inverter is on the power supply, 4 outputs (2 transformers). I
haven't separated the diffuser sheets from each other in an effort to
prevent contamination and to avoid incorrect orientation on reassembly,
and have partially reassembled the screen to keep everything together
while I try and locate a tube.

With another tube connected, plus the 3 good ones in the screen, the LCD
works fine and displays a good image. With the bad tube in place the
inverter will shut off a few seconds after power up. Initally before
this diagnosis we had tried patching in a seperate inverter but the
symptoms were identical.

Since it's only a cheap unit we have decided to take this approach
rather than scrap the unit, since it would not be worthwhile to replace
the whole LCD. Owner intends to use it as a bedroom set if we can get it
functional.

In the USA we use CCFLWarehouse or their eBay store, Plasmo
Industries. Possibly one of them would ship to the UK for a
reasonable price.

Don't worry about the longer pins on the replacement CCFL, just trim
them to length before soldering.

PlainBill