Polaroid 37" making loud squealing noise/black lines through display

[Skellums]

Hey all,

First time poster here. My parents recently bought themselves a 46" Sony LCD, and gave my wife and I their old Polaroid 37" as it wasn't working. As the title reads, when you first power it on, there is a very loud squeal that comes from the speakers. If the TV is muted, the sound stops, but continues if unmuted and the volume is set to 0. There is also a faint black strip (it's not a straight line, it's more curvy than anything) on the right hand side of the display.

Anyway... Being as it was a free LCD TV, I'd like to see if I can get it fixed up. I took it apart, as from previous experience with fixing my Samsung monitor (which was repaired following a previous poster's experience with the same model on these very forums), I figured it was some bad caps on the power supply. Lo and behold, there are a couple of bulging caps on the thing.

My experience with capacitors is limited.. I don't know how the sizes are measured (10x16, 10x20, etc). I understand the electronics side of thing as far as the capacitance goes. All of the caps on the board look to be CapXon. The ones that are bulged read 1000uF 10v KF 105°C. I realize it's probably best to replace all of them rather than just the bulged ones, so any pointers on how to "measure" them would be helpful!

Would this likely be the cause of the squealing? I've attached some pics of the board if it helps.

[kc8adu]

Re: Polaroid 37" making loud squealing noise/black lines through display

very common on that set.i had plenty of panasonic fm 1500@6.3 so i use them.
i replace all caps on the secondary to be sure.
but replacing the 2 bulgers will fix the set.

[Skellums]

Re: Polaroid 37" making loud squealing noise/black lines through display

Replaced the bulgers, the set is now working awesome! The black streak is still going through it, I'm thinking it might be physical damage to the screen now though.

If anything else goes bad, I'll replace the rest. Thanks a bunch kc8adu!

[Wizard]

Re: Polaroid 37" making loud squealing noise/black lines through display

Take a pic of whole LCD and the streak itself and post here for us to see.

Cheers, Wizard

[Skellums]

Re: Polaroid 37" making loud squealing noise/black lines through display

Here's the pics, it's kinda hard to capture the streak, as it doesn't appear unless it's a certain colour/brightness. If it's full on white, you can't see it, if it's dark you can't see it.. It only shows up with in-between shades.

In the first pic, you can see it in the purple panel to the right of the guys head (the blur at the bottom was just me removing the advertisement's website). You can see it in all of the pictures.

I don't know if it was related to the cap blowing out or just something that happened to the panel. I'm not too concerned about it, most times I barely notice it's there unless the colour/brightness in the scene is just right.

[kc8adu]

Re: Polaroid 37" making loud squealing noise/black lines through display

thats a bruise or pressure mark.
something hit the screen at some time.
options are to live with it or replace panel.

[Krankshaft]

Re: Polaroid 37" making loud squealing noise/black lines through display

That's why I like CRTs you don't bruise them if you whack em they bruise you .

[Wizard]

Re: Polaroid 37" making loud squealing noise/black lines through display

Heh. You done good job on caps, just live with it. Annoyingly.

You can happen along a compatible panel and swap it from another same size and have same plug design.

Cheers, Wizard

[BADHIGEEN]

Re: Polaroid 37" making loud squealing noise/black lines through display

could you mabey heat that scare out with a hot air gun if you dismantle the set?
those pics of the powerboard and the 2 bulgers are identicle to my 37 polaroid bulgers. my brother has the same set and it has died hope its an easy fix.

[BADHIGEEN]

Re: Polaroid 37" making loud squealing noise/black lines through display

here is the pic to compare

[Skellums]

Re: Polaroid 37" making loud squealing noise/black lines through display

Yeah, it was a nice quick fix to repair the bulgers, from searching around it seems to be a common issue with this set. Works like a charm now! Squeal is gone, and starts up within 10 seconds, where before it was almost 30 seconds before anything showed on the display.

As for the heat gun, would that potentially work? I'm not too keen on taking the panel out unless there is a possibility

[rehjar01]

Re: Polaroid 37" making loud squealing noise/black lines through display

hello , I have the same 37" polaroid w/ very loud squeal going to check cap thanks for the help!!

[cadillacman]

Re: Polaroid 37" making loud squealing noise/black lines through display

ive got 2 under my belt. Those are awesome sets to fix cheap.(usually)

the bruise, that sucks man. Ive had mild success with some massage action at random times durning my 48hr burn-in tests but hey screw it unless it really bugs ya id just live with it

[Skellums]

Re: Polaroid 37" making loud squealing noise/black lines through display

2 1/2 years later and the set is still kickin'

Still has the bruise mark (I think it's a heat mark actually, it's gotten worse since I fixed the caps). I barely notice it now though. It's not my main set, just a bedroom TV to watch before bed.

Good luck with the caps, it was a cinch to fix them. I may need to replace mine again soon (or just toss the set). After being on for a while, if I turn it off I have to let it cool down before it will power on again.

I haven't looked at the PSU again as it's not really a bother. It only sucks when I accidentally set the sleep timer and it turns off in the middle of watching something, haha. I have to wait usually 10 minutes before I can get it to turn on again!

[cadillacman]

Re: Polaroid 37" making loud squealing noise/black lines through display

yup time to recap it again lol also check for krappy solder joints..

[VW1369]

Re: Polaroid 37" making loud squealing noise/black lines through display

I have a TDA 03211c Polaroid with the loud squeal problem, picture distortion and the power button stops working! I unplug it for a few and it works fine for a couple of hours. All the capacitors look fine visually. Lil' help???

[tom66]

Re: Polaroid 37" making loud squealing noise/black lines through display

Replace the caps anyway -- they can still cause this.

I have worked on this TV, but branded "Bush". They used to make good stuff until Argos bought the name, then they just started slapping it on any old tat they could import from China.