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Equipment Repairs => LCD TV forum => Topic started by: Turnip on August 31, 2018,12:19:59

Title: Panasonic TX-39AS600B - Backlight issue.
Post by: Turnip on August 31, 2018,12:19:59

Hi folks,

Have one where the four backlight feeds show - 31.5/31.5/31.5/40.7 volts on the tester.

Bit odd, as suspect 40.7 dubious, but can't imagine what might cause it - Chris.

Title: Re: Panasonic TX-39AS600B - Backlight issue.
Post by: astracat on September 02, 2018,09:54:06

hi turnip
may be led strip  not taking current ie o/c on 40volt strip?
regards
astracat

Title: Re: Panasonic TX-39AS600B - Backlight issue.
Post by: Turnip on September 02, 2018,10:26:37

Hi Cat,

With an O/C strip my meter reads around 220v so 40.7v looks a bit odd - Gained 9.5v somewhere, guess take it apart and have a look. Would have done already but waiting for glue to set those big lenses on an LG so's I don't get 'bright patches'

Was a bit of an issue as the LG  Leds had the cathode pad bigger than the anode, and I only have 6v LGs' with big anodes, so had to scrape the track away a bit as otherwise they short out - Nothing on Ebay at the moment - Chris.

In the event the Pana had just one duff Led. Bit of a problem as they're 4mm x 2mm and the cathode has the larger pad.
Nothing on Ebay so used a standard square LG Led soldered in the other way around. Guess have to improvise.