Philips 42PFL9632D/79 2-secs-to-black

[pedro]

Re: Philips 42PFL9632D/79 2-secs-to-black

You didnt actually say what happened when you heated the master inverter from cold.
If that made it work then I would change the caps only a couple of dollars to try..

EDIT
Haha I see why - I am a day behind/ahead/below/above or something. Will look in later

Today I applied the heat gun blast - probably 50C-60C - to the master inverter, aiming it across the two Samwha LT caps and trying to avoid the rest of the board while repeatedly trying to start it. After about 4 minutes it fired up and remained running until I chose to shut it down, and then it was able to be restarted straight away. Symptomatic of ESR failing, but all four caps showed 0.02 ohms on the ESR meter when cold so I'm not automatically assuming replacing them will fix the set. I figure on replacing them anyway, but that's when a new PITA appeared.

These caps lie in a slot in the inverter board(s) measuring 22.5x8.2mm. The Samwha's are 21 long x 10 diameter, with their underside flush with the bottom of the pcb (saving ~1.6mm of height compared to lying directly on top of the board) and their upper side is the proverbial bee's dick below the metal shield. Normally I would select Panasonic FM or FR for this job, but they are larger - the FM is 12.5 diameter x20 while the FR is 25 long x10dia. Extending the slot by enough to take FR's looks out due to trackwork on the slave. Maybe widening and bevelling the slot would allow FM's to fit, but there is only 2mm below the board to the chassis so the shield may require some custom redesign. Sigh!

[martyparish]

Re: Philips 42PFL9632D/79 2-secs-to-black

I would try other brands to see if they have one that matches in size. United Chemcon / Rubycon / Nichicon should do fine

[selldoor]

Re: Philips 42PFL9632D/79 2-secs-to-black

I was thinking that but couldnt spot the values uf &v to look it up. Someone has 470uf 35v
so a fm would fit so I suspect the values are not the same

[retiredcaps]

Re: Philips 42PFL9632D/79 2-secs-to-black

Symptomatic of ESR failing, but all four caps showed 0.02 ohms on the ESR meter when cold so I'm not automatically assuming replacing them will fix the set.

Did you measure the caps in circuit or out of circuit?

[tom66]

Re: Philips 42PFL9632D/79 2-secs-to-black

Retiredcaps makes a good point. The low esr ceramics on the board can make the ESR of the electrolytics look low.

[pedro]

Re: Philips 42PFL9632D/79 2-secs-to-black

I would try other brands to see if they have one that matches in size. United Chemcon / Rubycon / Nichicon should do fine

The caps are 680u/35V. From available sources here (I don't want to wait/pay for indent, been bitten before by Farnell USA ...) I looked at Nichicon, Rubycon and Panasonic.

Rubycon 35ZL680MEFC12.5X20 - too fat.
Rubycon 50ZL680MEFC12.5X30 - too fat and too long.
Nichicon UHE1H681MHD 12.5 Dia. x 31.5mm - too fat and too long.

Retiredcaps makes a good point. The low esr ceramics on the board can make the ESR of the electrolytics look low.

In circuit. Appreciate the effect of other caps, was only looking for variation and to see if tacking another cap across each as a diagnostic move would achieve much. But if the overall ESR at that point is that low, it'd take a decent cap to lower it materially. May still try that, depends what I have in a 35V rating here. Most of my stockpile of low-ESR caps is leftovers from monitor repairs, not much call for 35V there.

[retiredcaps]

Re: Philips 42PFL9632D/79 2-secs-to-black

I looked at Nichicon, Rubycon and Panasonic.

You missed

http://www.digikey.com/product-detai...514-ND/2504783

[pedro]

Re: Philips 42PFL9632D/79 2-secs-to-black

You missed

http://www.digikey.com/product-detai...514-ND/2504783

You missed

From available sources here (I don't want to wait/pay for indent, been bitten before by Farnell USA ...) I looked at Nichicon, Rubycon and Panasonic.

[pedro]

Re: Philips 42PFL9632D/79 2-secs-to-black

You missed

http://www.digikey.com/product-detai...514-ND/2504783

Interestingly, 680/35 in the Pana-cattledog (p.26/80) shows two products and two sizes - EEUFR1V681 is 20x10 and EEUFR1V681L is 25x10.

It seems that the only one of those carried by RS in Oz is the long ("L") one.
http://australia.rs-online.com/web/p...erm=EEUFR1V681

and the same result comes through their parametric search.

On the matter of international shipping (USA->Australia), I have NEVER had a sensible price/speed tradeoff experience. The most recent was Farnell with $14 worth of bits and $34 shipping via USPS Expedited International, which took three weeks, and this was *after* I had asked their support people what was the most affordable way for the shipment. I've used Fedex all around the planet, and I would have expected this to be ~$25 using them, but Farnell insisted it would have been $75-$80 on Fedex. When I can get overnight across Australia for <$10 (and free if an online order thru RS-Oz) I'm prepared to pay a bit extra for the actual parts, but I'm not interested in waiting much longer than that or paying over the top for delivery.

[selldoor]

Re: Philips 42PFL9632D/79 2-secs-to-black

How do these rate for shipping

http://www.x-on.com.au/Results.aspx?srchVal=EEU-FR1V681

[pedro]

Re: Philips 42PFL9632D/79 2-secs-to-black

How do these rate for shipping

http://www.x-on.com.au/Results.aspx?srchVal=EEU-FR1V681

X-On are really good for delivery (next day) and for stocked lines delivery costs around $15. They have done BOM lists for me for production assembly projects in the past and I would highly recommend them to anyone in Oz.

On that linked page there are five line-items. All are 3-5 days which means ex-Mouser, and the delivery cost goes up with that. But I will follow up with them after the weekend. Thanks for that. Farnell (aka element14) show them as 6-7w/days ex UK.

As an aside, the Samwahs showed 0.02 ohms in circuit, and the same out. Before people jump to the conclusion that the meter is u/s, the board shows 0.28 where each cap was, so board contribution was insignificant in measuring them in circuit. Also the spec for the Panasonic FR is ... 0.02 ohms.

[selldoor]

Re: Philips 42PFL9632D/79 2-secs-to-black

It may well be that the caps will not help!!! I originally just thought it was something
quick and easy and cheap to try. That would seem not to be the case. I am spoiled here as I live only half a mile from a farnell trade counter so no charges.
May be worth doing further more concentrated heat tests - Instead of hot air try heating the solder joints on the caps with a soldering iron.

[pedro]

Re: Philips 42PFL9632D/79 2-secs-to-black

It may well be that the caps will not help!!! I originally just thought it was something
quick and easy and cheap to try. That would seem not to be the case.

Normally if I open up a monitor I'd be as inclined as not to replace any dodgy-brand caps on sight, and the cost is not a deterrent but delays in waiting for bits can be a PITA, especially as a 42" teev ties up a table because it won't fit on the service bench!

I am spoiled here as I live only half a mile from a farnell trade counter so no charges.

Half your luck. I'm about 10km from X-On but they don't allow pickups except for big $$$ clients. There's an RS counter about 25 minutes away, but there's f-all stock of any consequence held here in Perth. So pretty much everything is overnight.

May be worth doing further more concentrated heat tests - Instead of hot air try heating the solder joints on the caps with a soldering iron.

I'd already stripped and resoldered those joints with *real* solder at the same time I did the transformer secs.

I set up a "fence" of cardboard between the controller IC and the caps to try and isolate hot air and keep heating effects separate. Over the hours I've been alternately trying heating each of those, but *either* results in starting after a minute or so when the other is unheated so no conclusion yet. But given that the caps' cold ESR matches the FR spec, heating them (to reduce ESR) should be a non-event in terms of changing startup behaviour.

[martyparish]

Re: Philips 42PFL9632D/79 2-secs-to-black

Not sure what your board numbers are(can you post them and maybe nice close ups?), but there is a mod from LG. see attachment.

Also, see this thread, it may be of use:

https://www.badcaps.net/forum/showth...t=10215&page=3

[pedro]

Re: Philips 42PFL9632D/79 2-secs-to-black

The boards are the LC420WU5 that have cropped up in other threads, sometimes listed as PNEL-T707A and -T708A. I have reviewed all the other threads on this forum that came up under any of those numbers.

There are two different mods for this pair of boards, one ex LG and the other from Philips. They are intended to limit recurrence of failure of the BD9897FS controller chip. In this set neither board has a failure as such, just the master won't start unless something is warmed up. There is little point posting a photo as the boards have no visible degradation or damage whatsoever. Anyone who is curious what these boards look like can find pictures of them all over the net.

[martyparish]

Re: Philips 42PFL9632D/79 2-secs-to-black

Anyone who is curious what these boards look like can find pictures of them all over the net.

No disrespect, but you are asking for assistance, so telling people to go search and find pictures of your boards isn't gonna help your cause. Good luck with it.

[selldoor]

Re: Philips 42PFL9632D/79 2-secs-to-black

Steady on Marty. Did you read the whole thread - Pedro is a pro tech and has been a member on here for along while. It is fairly obvious he has read all the threads and the LG
fix has already been mentioned and commented on. There is also a pretty good picture of the slave board posted by Pedro which clearly shows the part number so your request was maybe less valid than you thought?

[martyparish]

Re: Philips 42PFL9632D/79 2-secs-to-black

I said "no disrespect" I'm sure Pedro is a fine tech! However that doesn't change the fact that the most helpful users here(you included) are probably quite busy. I have followed the thread from the beginning and the pic you mention is not good quality.

[selldoor]

Re: Philips 42PFL9632D/79 2-secs-to-black

the pic you mention is not good quality.

Haha - youve not been on here as long as I have I was going to start a library but it was too depressing

here are two fine examples

[pedro]

Re: Philips 42PFL9632D/79 2-secs-to-black

I said "no disrespect" I'm sure Pedro is a fine tech! However that doesn't change the fact that the most helpful users here(you included) are probably quite busy. I have followed the thread from the beginning and the pic you mention is not good quality.

The pics I posted were for identification purposes only and not for diagnosis as I stated in the accompanying description at the time. I do believe that there is nothing that experienced eyes can determine from looking at pics of the board in question. If someone *really* wants a pic I'll post one although I sincerely believe it will be a waste of my time. But ask away.

Yes, I *am* welcoming help or I wouldn't have posted here at all. I don't take offence at criticism, but I must admit I do get a bit short when people ask questions that have already been answered earlier on - and that's not you Marty. At the moment I'm still trying to find a leakproof way to heat *only* the caps or *only* the BD9897FS, as I don't like working on SMD chips with 0.8mm pitch if I can avoid it.