My aged MIL has a 36" Samsung LCD TV. It’s about 5 years old now. No, I don’t know the model # (yet).
Recently it has started to have problems. After running for 5-10 minutes the darkest areas of the picture begin to turn a weird dark green color.
The edges of the discoloration aren’t stable, they vibrate & froth a bit. It looks sort of like green-screen bleed-through you used to see in the old analog days when the person in front of the green-screen is wearing almost the wrong color. Just to clarify, this happens on any image; actual green-screen broadcasting has nothing to do with this.
Over the next few minutes the “green blob” as she calls it will slowly expand from just the darkest areas to cover more and more of the screen. Eventually almost the entire screen is this flaky flickery green.
I’ve confirmed the problem is in the TV, not the cable box, DVD player, etc. It happens equally on every source, every channel, etc. And the severity is proportional to the time the TV has been on, not the time any of the sources have been on.
She uses the thing just a couple hours a day so it’s not like it’s been burned in 24x7 for 5 years straight. She’s willing & able to get a new one, but was happy with this one before it started acting up.
It seems pretty obvious to me that it’s a heat-related problem in the TV. My question is whether it’s practically repairable. I can certainly open it up & blow out any dust. And while I’m in there look for loose connections, bad solder, etc. But unlike a PC there are no cooling fans, so IMO/IME TVs don’t tend to accumulate the volume of heatsink-clogging dust that PCs do. And with modern electronic construction I don’t realistically expect to be able to see anything amiss; any defect is likely in an interior layer of a circuit card or in/under an SMD.
Probably not. The good news is that 36" TVs can be found for well under $200. Is her birthday coming up soon? Did you miss Mother’s Day in May? Early Christmas present?
Sure it is. the question is: do you want to spend >$250 on a repair, when you can buy a new one for $400? I had a similar problem witha Philips/Samsung set. It was a failed power supply board-it would have cost $300 to fix. A new ,better set was $400.
Probably repairable but the cost of the repair might be equal to the purchase price of a recent and much better TV. The TV repairman is going the way of the milkman if he hasn’t already.
I’m not sure TV are supposed to last more than 5 years. I think the expectation is that half a decade later, you’ll be able to purchase something much nicer for relatively cheap.
Inspection with a Mark 1 Eyeball is free. A quick scan of the web shows Samsung has had problems with bad power supply capacitors in many models across many years, so look for bulged or burst caps.
If that’s the case, you can probably fix it for five or ten bucks. Looks like you need “high heat” capable caps, which are probably not a Radio Shack item.
A lot of problems in these kind of electronics are due to badly made capacitors. It’s been going on for a surprising number of years.
Most of the time they can be spotted visually: the top is bulging and sometimes the electrolyte is leaking out. (You need to be able to tell the difference between leakage and glue holding some down.) But some need to be electronically tested.
Usually the bad ones are in the power supply. Which are easy to id, replace, etc. if you have soldering skills. But your symptoms suggest the bad ones (if they exist) are elsewhere. Harder to track down, reach, replace, etc.
So … 5 years? Toss it.
Note: Unlike CRT TVs, once you unplug an LCD TV, there’s not much of a chance of harming yourself once you take the back off. OTOH, putting it back together wrong can create a hazard.
Thanks all. The consensus pretty well matches my going in assumptions.
My undergrad was combined EE & comp sci, and I’ve done electronic hobbying back in the HeathKit days, so I know my way around the innards & could plausibly & safely fix anything that was visually obvious. I gotta say my enthusiasm to break my now antique soldering station out of mothballs ain’t real high; this has all the earmarks of a multi-day goose chase with several trips across town to pick up, deliver, chase parts, etc. Thirty years ago I’d have relished the challenge; nowadays I’d rather wave my wallet at the problem & go to the beach instead.
For comparison I stopped by the cheapo discount electronics store today and on their 4th of July Super Sale !!!1! I can get a similar or slightly bigger name brand unit for $400-500. A no-name box is more like 200-300. Might be time for Mom to get a shiny birthday present.
Bought an “RCA” brand LCD the same size as the old one for $179 on holiday super-sale. Problem solved in 30 minutes flat. Only issue remaining is I probably need to buy another HDMI cable to connect her DVD player since low-end TVs no longer have 3x RCA connectors.
Just in case anyone else inquisitive opens the thread, my success rate at repairing monitors by replacing caps is fairly high. Just this week a friend of my brothers asked me to look at a monitor for that very reason.
There are places online that specialize in selling you the specific caps you need - here’s one from Amazon for the Samsung 244T for example - you basically need to know the model, and you can find various places vying to sell you a bag-full of capacitors that are likely the problem.
Not for everyone, I’ll admit, but if you’re the type that enjoys breaking out the soldering iron, it’s worth a go.
Heh. Not only are there portable electronic capacitor testing devices, but the cool kids never buy anything from local stores unless they have no other choice. Digikey and mouser have pretty much every electronic part and chip in production for cut rate prices.
