i killed my television.

November 20, 2007 4:42 PM

my tv fell off a shelf and now the screen doesn't work. can i fix it?

i have no idea how it fell, btw. i think the house just settled and the shelf is a little wonky. it's a smallish tv, regular (not flatscreen).

anyway: the tv fell about 6 feet and landed screen-first on a carpeted floor. there are no visible cracks, nothing's loose, and the sound still comes through perfectly. however, there's no picture, not even on a menu screen or when i plug in my dvd. so i'm assuming that whatever sends the picture to the screen got knocked loose.

is it fixable? i'm actually getting a new tv in 3 weeks, so i'm not going to buy something else right now. i can live without television, but it would be nice to watch my dvds on something bigger than my laptop screen.

posted by thinkingwoman to technology (10 comments total)

If you heard an implosion, that would probably be the picture tube. Which you'd have to have replaced. Otherwise...?
posted by kittens for breakfast at 4:45 PM on November 20, 2007

oh, and there was no crunching or crashing, as i recall. just a thud. (although i was in another room, so who knows.)
posted by thinkingwoman at 4:57 PM on November 20, 2007

Televisions are not user serviceable! Please don't open it up, there are parts inside which can kill you, even if it has been unplugged for weeks.

It is also cost prohibitive to have it repaired (though you may want to consult your home owner's insurance, perhaps it is covered.)
posted by wfrgms at 4:57 PM on November 20, 2007

What wfrgms said. The capacitor in a TV is potentially lethal if you don't know precisely what you're doing. Do Not Open.
posted by darksasami at 5:15 PM on November 20, 2007

wfrgms writes "It is also cost prohibitive to have it repaired (though you may want to consult your home owner's insurance, perhaps it is covered.)"

Not necessarily. If you can find a convenient repair shop, take it in and get an estimate. I recently had a dead TV fixed for ~$80.

Definitely not a do-it-yourself job, however.
posted by mr_roboto at 5:30 PM on November 20, 2007

In case the earlier posters weren't urgent enough:

YOU CAN EASILY KILL YOURSELF!

EVEN if the TV IS NOT plugged in!
posted by sourwookie at 6:19 PM on November 20, 2007

It's possible to directly short the CRT anode with a plastic-handled screwdriver or similar tool, rendering the set safe to work on (usually). But it's not exactly the ideal method. And if you have no clue about these things in the first place you're probably just wasting your time.
posted by hjo3 at 6:25 PM on November 20, 2007

Nthing this: Please don't open it up, there are parts inside which can kill you, even if it has been unplugged for weeks.

TVs can kill you after being unplugged for years. DO NOT open the TV. Take it to a repair shop and get an estimate. If it's really just something loose, it'll be cheap to fix... if it's actually broken, it's probably not worth fixing.

If the place quotes you a high estimate, try getting a second opinion, just in case.

It's possible to directly short the CRT anode with a plastic-handled screwdriver or similar tool, rendering the set safe to work on (usually).

It is also easily possible to blow a hole in your hand or stop your heart. Don't do this.
posted by Malor at 8:42 PM on November 20, 2007

First of all, you really don't want to try and service this yourself, it is a stupid risk. Also, I recommend perusing the street during garbage day. You will probably find a working TV with an hour or two of looking. Craigslist a freecycle too, of course.


That said, the risks (as usual on AskMe) are somewhat exaggerated.

In general, high voltage is a risky thing to get involved with because it doesn't behave the way you expect it to. With high voltage there is a significant chance of arching, meaning that you don't even have to touch a live conductor - the charge will reach and shock you through the air! And, once the air starts conducting, it tends to keep on conducting, because it becomes ionized. High voltage is not forgiving of carelessness.

However, it isn't voltage that kills, it is current. The Fatal Current:

Electrocution occurs when a small, specific amount of electrical current flows through the heart for 1 to 3 seconds. 0.006-0.2 Amps (that's 6-200mA milliamps) of current flowing through the heart disrupts the normal coordination of heart muscles. These muscles loose their vital rhythm and begin to fibrilate. Death soon follows.

High voltage is both more, and less likely to provide such a shock, depending on circumstances. And, one interesting thing about that.. Capacitor discharges are much less dangerous than power supply outputs, because capacitors (except for really big ones) aren't likely to sustain a lethal current for long enough to do the job.

From a site on the repair of old TVs and Radios:

Mains-Derived EHT [Extra High Tension, aka High Voltage]

It is impossible to over-stress the dangers of mains-derived EHT systems found in pre-war and some early post-war sets. These systems are lethal, so treat them with respect. Unlike modern EHT systems, which are limited in the amount of current they can supply, these older systems using transformers straight off the mains can deliver enough current to kill an army. If you are not sure what you are doing, please ask a friendly colleague.

Emphasis added. Also, from the Sci.Electronics.Repair FAQ, TV Troubleshooting Safety:

The high voltage to the CRT, while 200 times greater than the line input, is not nearly as dangerous for several reasons. First, it is present in a very limited area of the TV or monitor - from the output of the flyback to the CRT anode via the fat HV wire and suction cup connector. If you don't need to remove the mainboard or replace the flyback or CRT, then leave it alone and it should not bite. Furthermore, while the shock from the HV can be quite painful due to the capacitance of the CRT envelope, it is not nearly as likely to be lethal since the current available from the line connected power supply is much greater.

By which they mean, many/most internal parts of a TV are not transformer isolated, and thus present a serious low/medium voltage electrocution hazard, and that the high voltage parts really aren't any more dangerous than the rest of a TV.

It is certainly not a case of "don't do this or you will die", as most would have you believe (unless the set is at least 25 years old).

Still, don't do it. Not worth it.
posted by Chuckles at 9:36 PM on November 20, 2007 [1 favorite]

I'm not sure of the situation in US but here in UK I wouldn't even think about repairing this TV. If it had just died, and the fault may be a blown fuse, I'd take the back off and check (I used to work in a repair shop, so I know a few tricks), but impact damage probably means that one or more of the tube elements has gone poof, even if the glass itself is still intact. Replacing a CRT would not be economical.
posted by No Mutant Enemy at 12:58 AM on November 21, 2007