TV makes a chirping sound which gets louder when the picture gets brighter

Hi,

I have a Finlux 3624(F) TV that makes an annoying high-pitched chirping sound. The sound is definitely coming from inside the chassis (not speakers). I know that there are a lot of possible sources for the sound, but decided to ask from you experts: Does the fact that the sound gets louder when the picture gets brighter give any hint about the location of the source? Is there something that could be done to fix it? Could it just be a bad soldering (I saw several suspecting ones when I opened the chassis)?

Also, the picture seems to have RG&B slightly off set from each other at least in the upper and lower part of the screen (clearly visible on borders of white and black, with blue vertical shadows right next to the left border and red to the right), but not in the middle. Is this a sign of a fault or of bad quality of the tube?

(I haven't had this set since new so I really don't know if the picture has been like that always, but I'd suspect it's possible.)

Also(2), this TV has had repeated problems with it's power supply (it has been repaired by local electronics students at least twice). I changed all the electrolyte condensators (capacitors) because it had problems powering up (again), and that problem seems gone now (well, for a while at least). Is it possible that a faulty component (possibly causing the chirping, too) has also caused the power supply to fail repeatedly? I have no idea what the students have done with the TV previously, though.

I haven't tried the "listening trough a cardboard tube with chassis open while turned on (!)"-trick yet, or "pokein' 'em components with a wooden or plastik stick or somethin'" (I found these tips by Googleing from this ng). Well I'm not sure I have the time (and courage) to those anyways ;) Depends on how annoying the chirping gets on my nerves in the long run.

Thanks for all the answers!

--
---- Ville Aakko - tel. +358503376817
Reply to
Ville Aakko
Loading thread data ...

Hi!

It seems the problem is with your ABL line (pin out of the LOT). It can also occur if the power supply is tinkered with resulting in the supply not matching the chasis.

Reply to
Wins

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.