Help sourcing PSU for Philips TV

[qc1998]

I have found a slightly different revisions of the same PSU board on ebay.

Take a look :
http://www.ebay.com/itm/Philips-2722-171-00702-Genuine-DPS-298CP-A-Power-supply-Board-New-in-Box-/381988285104?_trksid=p2141725.m3641.l6368
http://www.ebay.de/itm/Netzteil-DPS298CP-1A-aus-Philips-37PFL8404H-12-/182527130619?_trksid=p2141725.m3641.l6368
http://www.ebay.de/itm/Netzteil-DPS-298CP-A-fuer-LCD-TV-PHILIPS-37PFL8404-H-12-37PFL8684-H-GEPRUFT-/252776900985?_trksid=p2141725.m3641.l6368

I am not sure about these boards you found.
This revision (DPS-298CP-A) seems to be from the 37" TV. Mine (DPS-298CP-2) is a 47".
I'm pretty sure that the power requirements for a 47" are much higher than for a 37", so the revision difference is probably a difference in power rating.
(And for ~100EUR before shipping I am not willing to take the risk...)

Another issue is that those eBay listings don't seem to have shipping options for Israel...
(And from my experience with eBay, even if they would agree ship them here, the price would probably be too high) 

Again, I might try to get one of those different revision boards as a last resort, if/when my TV stops working completely...
(Or when I find one for under 50$)

You have mentioned that you have replaced the ceramic capacitors and it did not help.
Were you talking about the capacitors I marked on the picture ?
Are they the same capacitors offered here :
http://www.electronic-doc.de/kondensatoren/420-reparaturset-dps298cp4a-2x33pf-2x47pf.html?search_query=DPS-298CP&results=21

Yes, those look like the capacitors I replaced.
(Though I got mine from RS Components)
And as I said before, it didn't change anything...

You might try whatever similarly sized CCFL transformer you can find, the specs tend to be very similar even if they don't look quite the same. There are lots of ccfl transformers on ebay, or you could set up a saved search for your TV model that will alert you if any parts for it get listed. Often you can buy boards from scrapped TVs.

Your suggestion to look for a backlight transformer from another model would make sense, but there is a 'slight' issue:
I'm not an expert on TV design, but I think these Philips panels have a different backlight design than most 'typical' LCD TV's.
On most TV's I've seen there are quite a few (4-10?) small transformers, each driving one CCFL lamp.
On these Philips panels, there is a single large transformer which drives all the CCFL lamps. (Which are probably connected in series)

Anyway, as I wrote before, I was able to get a PSU from a different Philips TV that seems to have electrically similar design, but the footprint for the transformer is not the same.
I might try to 'bodge' it onto the board when my transformer dies completely.

As for using the search function on eBay, I have already set up an alert for this PSU board over a year ago, but nothing comes up.
I guess this TV was not that popular (which makes sense considering how expensive it was at the time) or that they might all share the same failure mode, making getting a working PSU pretty hard...

Anyway, thanks.

[james_s]

I don't remember what brand it was, but I once scrapped a TV that had a smashed panel, it had electrodeless CCFL tubes that were all wired in parallel and RF driven. I think it was a Vizeo but I wouldn't swear to it.