Philips Plasma 50PF7320/10 worth anything?

[PowerAmpFreak]

Hello!
I have the chance of buying a dead Philips plasma model 50PF7320/10 for about 70USD. According to the owner neither screen or sound works. It's about 4 years old. The question arise, is this a good thing to buy? Are there big chances I can get this set up and running. Some of you (PlainBill? Wizard?) has probably been involved in servicing those, right?
Thanks for your comments, please!

[PlainBill]

Re: Philips Plasma 50PF7320/10 worth anything?

Hello!
I have the chance of buying a dead Philips plasma model 50PF7320/10 for about 70USD. According to the owner neither screen or sound works. It's about 4 years old. The question arise, is this a good thing to buy? Are there big chances I can get this set up and running. Some of you (PlainBill? Wizard?) has probably been involved in servicing those, right?
Thanks for your comments, please!

I doubt if either of us have serviced them. A /37 would indicate a North American model; I'm not sure what area Philips uses the /10 for. PAL/SECAM, anyway. The service manual is available on Elektrotanya. The information I have is the set went out of production in July, 2006, so either the seller has one of the last one's produced, or has a very flexible memory.

I HAVE worked on the US version of the 42" model of this TV. It was notorious for the 'two bad caps' problem, which cost about $5 to repair. The power supply is different, however.

PlainBill

[PowerAmpFreak]

Re: Philips Plasma 50PF7320/10 worth anything?

I got the price down to about 55$. I think it's worth that amount.
It seems it's a decent TV. I will pick it up tomorrow, start working on it later this week. More posts in this thred for sure!

[PowerAmpFreak]

Re: Philips Plasma 50PF7320/10 worth anything?

I opened up the plasma today and noticed pretty fast two bad caps on the powersupply board, see attached picture.
I think this is the secondary caps for +5V supply.
If this is all that is bad in this plasma I'll be a very happy guy!
What seems strange, I downloaded the schematics for this set and in this manual there's a philips powersupply. But in my set there's mostly samsung boards. Could it exist two different powersupply boards for the same model?

[PlainBill]

Re: Philips Plasma 50PF7320/10 worth anything?

I opened up the plasma today and noticed pretty fast two bad caps on the powersupply board, see attached picture.
I think this is the secondary caps for +5V supply.
If this is all that is bad in this plasma I'll be a very happy guy!
What seems strange, I downloaded the schematics for this set and in this manual there's a philips powersupply. But in my set there's mostly samsung boards. Could it exist two different powersupply boards for the same model?

Holey Moley!!! That's the classic 42PF7220 fault!!! 3300 uF, 10 Volt, right?

OK, training lecture #103. Plasma TVs are somewhat weird. There are only a limited number of manufacturers who make plasma panels. When Samsung (or LG Electronics) markets a plasma panel, it includes the actual panel itself, the Y and Z sustain cards, Y buffers, X drivers, the main controller card (hidden behind the Small Signal Board), and the power supply which provides the voltage for the above cards.

A TV manufacturer will buy the panel, add the Small Signal board, audio amplifiers, speakers, bezel, side input connector, control buttons, etc.. As part of the service, Samsung will customize the power supply so it also provides power for the the TV manufacturer's assemblies. Thus a Philips TV and a Sony TV that use the same Samsung panel will have the same sustain cards, buffers, main controller, etc, but a slightly different power supply, and of course you will never find a Sony TV with Ambilight.

On a Philips TV it is very easy to distinguish between the Samsung parts and the Philips parts. Look at the screws holding it in place. Samsung uses philips screws, Philips uses Torx screws.

PlainBill

[PowerAmpFreak]

Re: Philips Plasma 50PF7320/10 worth anything?

yes, you're correct 3300uF/10V.
These days I begin to understand how Plasma TV's are built, like you say, panel and driver boards and custom psu. But why did Philips even bother designing their own psu for this model when Samsung already provided this?

[PlainBill]

Re: Philips Plasma 50PF7320/10 worth anything?

yes, you're correct 3300uF/10V.
These days I begin to understand how Plasma TV's are built, like you say, panel and driver boards and custom psu. But why did Philips even bother designing their own psu for this model when Samsung already provided this?

No, no, no! The power supply Samsung designed would provide the voltage / current necessary for the Small Signal Board and audio amplifier. Samsung took their standard power supply design and added the circuitry necessary to provide power for those.

It's much easier to sell a plasma panel if you tell your customer "Heck, yes!! We'll be glad to provide 12V at 3 Amps and +-18 Volts at 2 amps for you." rather than "We only provide the voltages our panel needs - you have to figure out how to provide the rest. What do you think we are - Design Engineers?".

PlainBill

[PowerAmpFreak]

Re: Philips Plasma 50PF7320/10 worth anything?

Yes, I get this. But in the service manual it's not the Samsung powersupply. It's a totally different Philips powersupply.

[ifr500]

Re: Philips Plasma 50PF7320/10 worth anything?

I must have the same service manual as you. lol
My plasma has the black screen,the two caps look fine but i will change them.
Good Luck

[PlainBill]

Re: Philips Plasma 50PF7320/10 worth anything?

Yes, I get this. But in the service manual it's not the Samsung powersupply. It's a totally different Philips powersupply.

OK....???

PlainBill

[PowerAmpFreak]

Re: Philips Plasma 50PF7320/10 worth anything?

Anyways, I changed the two 3300uF/10V caps but there are some more problem with the powersupply unfortunately.
It seems all the "low" voltages appears normally, I mean 3V3, 5V, 12V and so on. Even VA operates correctly at 70VDC.
But the higher voltages like VS, VE, Vscan does not come up at all.
These voltages appears to come from the main smps part which according to my measurements on the primary side half bridge, doesn't oscillate.
So, when plugging in the set, the low voltages come up for one or two seconds, then the set shuts down in protect mode and the standby led flashes.
How can I get the schematics for the Samsung powersupply?
Or perhaps Plainbill (!!!) has some more great advice (as allways)

[PlainBill]

Re: Philips Plasma 50PF7320/10 worth anything?

Anyways, I changed the two 3300uF/10V caps but there are some more problem with the powersupply unfortunately.
It seems all the "low" voltages appears normally, I mean 3V3, 5V, 12V and so on. Even VA operates correctly at 70VDC.
But the higher voltages like VS, VE, Vscan does not come up at all.
These voltages appears to come from the main smps part which according to my measurements on the primary side half bridge, doesn't oscillate.
So, when plugging in the set, the low voltages come up for one or two seconds, then the set shuts down in protect mode and the standby led flashes.
How can I get the schematics for the Samsung powersupply?
Or perhaps Plainbill (!!!) has some more great advice (as allways)

FIRST STEP!!! Count the flashes of the red led!!! It should be a several flashes, a short pause, more flashes, a long pause, then repeat. The standby processor has detected a problem and is flashing an error code. That will tell you where to check.

PlainBill

[PowerAmpFreak]

Re: Philips Plasma 50PF7320/10 worth anything?

First I began to count the amount of flashes. BUT, since the set isn't in SDM mode (service mode) the flashing will be continous.
To put the set in SDM mode you have to press a number sequence on the remote, I tried this but since it already detected a problem I cannot enter SDM.
I quit count at 24.
I really want to get this up and running!!

[PowerAmpFreak]

Re: Philips Plasma 50PF7320/10 worth anything?

Hmm, According to the service manual I can short service jumper on SSB, then the processor will output error buffer as flashing sequence.
First thing tomorrow.

[mockingbird]

Re: Philips Plasma 50PF7320/10 worth anything?

Samsung uses philips screws, Philips uses Torx screws

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[PowerAmpFreak]

Re: Philips Plasma 50PF7320/10 worth anything?

When powersupply starts from standby mode, there is no logic explanation why VS supply doesn't come on, except for local problem isolated to powersupply, right? I mean, VA comes up to normal levels, and at the same time VA supply is started, VS should start aswell, right?

[PlainBill]

Re: Philips Plasma 50PF7320/10 worth anything?

First I began to count the amount of flashes. BUT, since the set isn't in SDM mode (service mode) the flashing will be continous.
To put the set in SDM mode you have to press a number sequence on the remote, I tried this but since it already detected a problem I cannot enter SDM.
I quit count at 24.
I really want to get this up and running!!

They may use different firmware 'Down Under'. Here on the top side of the world the flashing pattern stars automatically whenever the TV goes into protect mode, and continues until the plug is pulled. Does the service manual you have discuss protect mode?

PlainBill

[PowerAmpFreak]

Re: Philips Plasma 50PF7320/10 worth anything?

The service manual is available here:
http://www.eserviceinfo.com/download.../PHILIPS_.html
There are a chapter discussing error codes and how to generate flashing error codes (put the set in Service Default Mode (SDM).
The error codes in the list is generally only I2C bus stuff.
I will try the service jumper today, though the manual recommends to do this for only a short time since the 8V protection is deactivated.

[PowerAmpFreak]

Re: Philips Plasma 50PF7320/10 worth anything?

The Samsung powersupply board is marked LJ44-00108C PS-504-PH rev0.7
It should be very interesting to see a schematic for this board.
This board, or some variant, must be used in other models aswell.

[PowerAmpFreak]

Re: Philips Plasma 50PF7320/10 worth anything?

I did exactly how the service manual told to enter Service Default Mode (SDM). 1. Short jumper marked "SDM" on SSB in prior applying mains.
2. Apply mains.
3. Take away the short on SDM jumper.
BUT, it appears the set never goes into SDM mode, since the standby led flashes without any error code generation at all.
The led is on 7 seconds, off 7 seconds and so on, in an endless loop it appears.
I'm afraid this indicate some major problem with the SSB, and the set is stuck in some kind of "hard-protect-mode", this ain't covered by the service manual unfortunately...