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Equipment Repairs => CRT TV forum => Topic started by: Contrast John on March 03, 2010,15:14:55

Title: Panasonic Euro 4H chassis
Post by: Contrast John on March 03, 2010,15:14:55

Hi All
Got one of these sets in for repair with a faulty (99% sure) digital module part No TNP8EF008. When tapped the picture disapears leaving a black screen with the sound ok. Tube heaters, EHT present and can hear 50Hz buzz from scan coils so frame probably ok. Tap the digi can and picture returns. It seems that these modules are no longer available. Has anyone managed to repair one of these modules or is replacement the only cure?
Regards
John.

Title: Re: Panasonic Euro 4H chassis
Post by: tv john on March 04, 2010,10:50:23

Hi John,a certain site mentions smd r1578 d/j,solder small elements on print side (?),ic1504 d/j and check
for d/j's on other smd parts.
Regards John.

Title: Re: Panasonic Euro 4H chassis
Post by: Contrast John on March 04, 2010,17:35:44

Hi John
Thanks for the info. Have already soldered the easy bits, but interesting about the `small elements' on the print side. Wonder if that might mean the drill holes connecting both sides of the board, some of which are solder filled? Will check out r1578 and try to pluck up the courage to resolder ic1504 ( multi legged smd video processor IC with legs bent under its body!). Customer has a loan set so I`ve got a little time with this one.
Will keep you posted.
Thanks again
John.

Title: Re: Panasonic Euro 4H chassis
Post by: tv john on March 05, 2010,08:44:54

Hi  John,r1578 is 10k and could be faulty,it sits between ic1504 and the connector strip. Also mentioned are the contacts from the socket to module,check resistance and clean or solder braid. These are notes I found .
John.

Title: Re: Panasonic Euro 4H chassis
Post by: Contrast John on March 05, 2010,18:00:25

Hi John
Thanks for the extra info. Fingers crossed I think I`ve sorted it. Decided to give r1578 a really close inspection under a x10 magnifier with a strong light and from several different angles. Could see nothing wrong with it`s solder connections, but resoldered it anyway along with its neighbour r1577 which also looked perfect. Fitted the panel back in the set and found the problem cured. No amount of tapping/flexing the panel or the nearby area can now induce the fault. Think I`ll probably swop the resistor anyway after reading your second post and keep the set on test for a few days. The two resistors mentioned are part of the circuit that monitors the crt emission.
Thanks again John, without your info I`m not sure I would`ve found this one anytime soon!
Regards
John.