Philips 32PFL3504D/F7 black screen

[Gorrillasnot]

Re: Philips 32PFL3504D/F7 black screen

bump

[selldoor]

Re: Philips 32PFL3504D/F7 black screen

Looks like we dont know - first line of help may be to ask the eseller.

If it came out of a different model with a different tcon and panel then
probably not compatible (The eprom may have different drivers)

[Gorrillasnot]

Re: Philips 32PFL3504D/F7 black screen

thanks for the reply.
I called shopjimmy's support number and they said it is indeed not compatible.
Sometimes I'm as dumb as a brick, but lesson learned. from now on I'll triple check all board numbers before ordering replacements.

ugh! this tv is a money pit and isn't worth it, but like Ernest P. Worrell I never new when to quit.

[selldoor]

Re: Philips 32PFL3504D/F7 black screen

Its not always just the number on the board - there is usually a barcode sticker that is the best number to get a proper match as it will be the same revision.

[Gorrillasnot]

Re: Philips 32PFL3504D/F7 black screen

yep I should of looked at the sticker, but I got into a hurry. I thought the number on the PCB was what I needed. Yet another rookie mistake, but I am learning.

anyone know if the wanted/for sale section of this forum is good to find a replacement board?
I briefly browsed the for sale part and it doesn't look very active.

thanks

[Gorrillasnot]

Re: Philips 32PFL3504D/F7 black screen

I ended up buying a complete board set on ebay and the TV now works...sort of.

When plugged in there is a buzzing sound coming from the PSU/main board. After pressing the power on button the buzzing briefly goes away until the back light comes on and the philips logo is displayed then the buzzing comes back on and I cant tell what board its coming from. To me it sounds like both boards are buzzing when the TV is powered on.

I watched a movie on the TV and the picture looks good, but during quiet scenes the buzzing/humming noise is very annoying.

I looked at the manual and flow chart 4 of the troubleshooting section shows about 20 things to check when buzzing can be heard from the power circuit.

I don't mind checking all the components listed in flow chart 4, but was wondering if there is a "usual suspect" that could be causing the buzzing?

thanks

[johnboy1313]

Re: Philips 32PFL3504D/F7 black screen

Are you sure you got all of the screws that hold the boards tight?

[Gorrillasnot]

Re: Philips 32PFL3504D/F7 black screen

yes all screws are tight. checked it again to make sure.

[Gorrillasnot]

Re: Philips 32PFL3504D/F7 black screen

bump

[Gorrillasnot]

Re: Philips 32PFL3504D/F7 black screen

bump

[Gorrillasnot]

Re: Philips 32PFL3504D/F7 black screen

bump

[Gorrillasnot]

Re: Philips 32PFL3504D/F7 black screen

The first power supply board I bought that I thought wasn't compatible actually worked after I swapped the inverter board with another one I bought on ebay so now the power supply doesn't buzz, but I am still getting a buzzing noise on the inverter board.
The humming/buzzing noise sounds like its coming from the middle transformer circled in red in the pic.

I tried swapping the transformer 2 different times with transformers I took off the original inverter board, but it is still making a noise.

http://s20.photobucket.com/albums/b2...psea6422eb.mp4
Its kind of hard to hear with my crappy camera but here is a video of what it sounds like.

Also I was wondering how to test the transformer (which pins to probe). I have uploaded a couple pics of one I took off the old inverter board.

I am stumped on what to test or replace to fix this humming/buzzing sound..anyone have any ideas?

thanks

[Gorrillasnot]

Re: Philips 32PFL3504D/F7 black screen

bump

[selldoor]

Re: Philips 32PFL3504D/F7 black screen

Well in the absence of other cunning plans how about swapping the buzzing transformer for one at the end of the board and see if the buzz moves with it. If not then the problem lies with the circuit . Could be caps bad bulbs leaky diodes.
Did you try moving the bulbs to see if the fault moves?

If it does move after moving the transformer then the perhaps try soaking the transformer in varnish - I believe it takes several dunks with lots of drying time between.

Anything on the back of the board? - You could also try moving the blue caps around
to see if it makes a difference. They go bad and give no sign - difficult to test

[Gorrillasnot]

Re: Philips 32PFL3504D/F7 black screen

I tried swapping around transformers but the noise stays on the middle one.
The bulbs seem good as far as I can tell. I mean I'm not sure how to check the bulbs but when playing a movie the picture looks fine.

I will try your suggestion on moving the caps around. I also have a spare board I can scavenge parts off of if need be.

thanks

[Gorrillasnot]

Re: Philips 32PFL3504D/F7 black screen

I took a little break, but back to working on this nightmare of a TV.

I have swapped allot of the blue caps around the buzzing transformer with ones I took off a spare board and also tried swapping the buzzing transformer with one on the end of the board but the buzz stays right where the middle 2 transformers are.

It's driving me nuts not being able to track down the bad part(s) that are causing the transformer buzz.
Anyone have any idea what the most likely culprit could be?

I would just buy another inverter on ebay but all the cheap ones seem to have disappeared. I bought 1 for $15 but it was poorly packaged and it arrieved with a big corner of the board broke off.
The cheapest boards I've seen in the past couple weeks were $40-$50 which is way to much for this old crappy TV.

thanks

[selldoor]

Re: Philips 32PFL3504D/F7 black screen

Are the components on the heatsink diodes? They look to have been hot maybe overworked if those 4 big caps are poor - perhaps change the caps as a first move then the diodes if they are diodes - I only see one.

[Gorrillasnot]

Re: Philips 32PFL3504D/F7 black screen

The one that can be seen down by the yellow transformer in the pic on post 32 is a Shottky Diode. The rest are transistors.

I've tried swapping the larger caps from a identical (but with a broken pcb) board and it made no difference. I suppose its possible the caps on that board are not good as well.
I may order some new ones.

In the picture I circled some things that I wasn't sure what they were, so I looked them up in the repair manual and it says that they are called Beads Inductors.
After a quick google it appears they are some sort of noise suppressors.
Do you think they have went bad or could be causing the transformers to buzz?

thanks

[selldoor]

Re: Philips 32PFL3504D/F7 black screen

Could be - cant say I have seen any like that before that I recall but if the manual says that is what they are and you can buy some got to be worth a try. Again you could try
moving them or if you have some on a spare board try them.

[Gorrillasnot]

Re: Philips 32PFL3504D/F7 black screen

Swapped the beads inductors from a spare board and it didn't fix the problem.
It was worth a try..On a positive note I am getting good practice desoldering and soldering though lol

I am close to fixing this TV. everything else works as it should...if I could just fix this dumb buzzing noise. grrrrr!

thanks