1989 Sylvania Superset TV - Burning Smell

[Vitam]

Hi! I cannot get the model number, but I have a 1989 Sylvania superset 13" TV. It works good after I adjusted the convergence and focus, but I noticed, on some areas of the board (mostly near the flyback) there is a "hot" or burning smell. The set works, however. No smoke. It's like when you turn on your heater after it being off all year, that bad smell. What is causing this, and is it dangerous?


UPDATE! I found a heatsink, with an ic on it, that is VERY VERY hot. It's pretty dusty too. Why is it doing this, can it be fixed?

[RukyCon]

Re: 1989 Sylvania Superset TV - Burning Smell

If you haven't used the TV in a long time then dust could have built up and now that it's running the dust is burning off.

The dust should not be too much of a problem [unless everything inside is covered in dust or the dust is blocking any vents] but you can get inside of it and use some canned air to blow the dust out if you need to.

[Vitam]

Re: 1989 Sylvania Superset TV - Burning Smell

I found the TV on the side of the road. I'll clean it, then see is there's any difference.

[Vitam]

Re: 1989 Sylvania Superset TV - Burning Smell

Okay even after through air compressed cleaning, it still makes the smell. what?!!!

[Vitam]

Re: 1989 Sylvania Superset TV - Burning Smell

Even after cleaning, it still makes the smell. What can this be?

[RukyCon]

Re: 1989 Sylvania Superset TV - Burning Smell

Can you post some photos.

[Vitam]

Re: 1989 Sylvania Superset TV - Burning Smell

Ok, one moment please

[Vitam]

Re: 1989 Sylvania Superset TV - Burning Smell

This is where I suspect the smell to be coming from.

Close up

[Vitam]

Re: 1989 Sylvania Superset TV - Burning Smell

Also, this set appears to be made by Philips Consumer Electronics.

[RukyCon]

Re: 1989 Sylvania Superset TV - Burning Smell

Are you able to read the numbers on the IC? That may be helpful.

[Vitam]

Re: 1989 Sylvania Superset TV - Burning Smell

I don't think I can.

[Vitam]

Re: 1989 Sylvania Superset TV - Burning Smell

I'll try later. Will remove chassis.

[Agent24]

Re: 1989 Sylvania Superset TV - Burning Smell

Looks like you are talking about the HOT (horizontal output transistor)? They do typically run rather warm, which is why they need the heatsink. But some faults can cause them to run incorrectly and oveheat, too.

You might want to have a look at: http://www.repairfaq.org/samnew/tvfaq.htm to start with, especially;
http://www.repairfaq.org/samnew/tvfaq/tvhorkboeh.htm and http://www.repairfaq.org/samnew/tvfaq/tvoldertvs.htm

[Vitam]

Re: 1989 Sylvania Superset TV - Burning Smell

Okay, nevermind the IC! I found this near the front of the board chassis.

What can I do about this? This is definitely where the smell is coming from. Definitely smelled like "hot fiberglass" !

[RukyCon]

Re: 1989 Sylvania Superset TV - Burning Smell

Do you have a multimeter?

[Agent24]

Re: 1989 Sylvania Superset TV - Burning Smell

There is an overvoltage problem or a overload on the power rail supplied by those resistors, I would guess.

You probably need a schematic at this point

[tom66]

Re: 1989 Sylvania Superset TV - Burning Smell

This can be normal after some time if the resistors run hot. It doesn't necessarily indicate a fault.

[R_J]

Re: 1989 Sylvania Superset TV - Burning Smell

I'v seen lots of tv's where the resistors get hot like this, I would check there solder connections and maybe clean and resolder them if they look bad. If there was any real problem I'm sure it would effect the picture in some way.

[Andrew F. Ali]

Re: 1989 Sylvania Superset TV - Burning Smell

I can see 12V TP12 and 80/90V TP15. Measure the Vdc at these Test Points. If they are read what is written on the Bd, then I would think you don't have problem.

[Vitam]

Re: 1989 Sylvania Superset TV - Burning Smell

R_J, I had to adjust the picture when I got the set. I had to adjust the convergence and flyback brightness and focus controls. Is this a fire hazard, or is the set safe to use until it dies?