I have a big 1989 CRT TV which I'm both in love with and genuinely fear. It recently took me extreme precautions just to eventually dare to open it up (after being unplugged for a long time) and just dedust it with compressed air and not even touch any part of its insides.

It strikes me that TVs must have been far more crude and dangerous if you back several more decades, or even in the 1970s. But let's say the 1950s, for example.

Did people in general have any idea about the dangers of opening up a CRT TV and poking around with your fingers inside? I can imagine that words such as these were uttered quite frequently:

That dang boob-tube is out of order again! But I'm not paying for another repairman... This time, I'm fixing it myself!

And even if a TV repairman could be called on the telephone and he just came over to your house, how did he stay safe? There is no time to wait for 24+ hours of it being unplugged, etc.

Did every TV that got sold have some sort of scary warning in the back saying that you must never open it up yourself under any circumstances? Were they told about this when purchasing the TV?

I frankly remember not-even-old people in the 1990s who would have all kinds of ornamental objects and even vases with water or other liquids on top of their TVs, almost as if they wanted to have an accident. If they had such little regard for general safety, or just didn't know better, what would happen if they attempted to poke around inside their set?

I have no idea how I would find this out myself, so I'm asking.

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    The very early tvs were made for easy repair. They had vacuum tubes in sockets. Pop out the one that was dark, get the number off the side, go to the hardware store test it, and get a new one.
    – justCal
    Dec 9, 2022 at 23:22
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    I had an uncle who was a TV repairman. If our TV acted up, we called him, described the symptoms and he would tell us which tubes to check. We would pull those tubes, go to the local store that had a tube checker (quite common in the 50's, 60's and 70's) and replace the bad tube. If that didn't work, my uncle would come for a visit, my mother would feed him dinner, and he would proceed to check out the TV. Of course, being this was his profession, he knew how to do this safely.
    – Barry
    Dec 10, 2022 at 0:14
  • I'm sure with some digging you could find documented deaths. Here's one anecdote I found with a quick search.
    – Brian Z
    Dec 10, 2022 at 3:57
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    Selected from a reply to the pinned comment here: "You wouldn't want too hot a spark, just enough to weld. You can use the tv's own EHT." So not only is it definite that you can kill yourself if careless, the voltage is sufficient to drive a arc-welding needed for the actual repair of "an open cathode weld". My wife's comment: "Anyone stupid enough to stick a screwdriver in there is doubly out of luck - because the Darwin awards hadn't been invented yet." Dec 10, 2022 at 12:52
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    My brother-in-law repaired TVs . The worst he saw was a child who had dropped candy through the holes in the back of the TV. The tubes could become rather hot. The candy had melted. And, voila, a big mess.
    – MasB
    Dec 13, 2022 at 16:59

3 Answers 3


The procedure to make a set safe for repairs is quite simple, if you know what you're doing. The danger, once the set is switched off and unplugged, is capacitors (formerly known as condensers), that will still be charged to high voltages.

The way to make the set safe is to discharge those capacitors, by shorting or grounding their contacts. Do not try this yourself. This is not enough information to do the job correctly. A trained repairer would be able to identify the capacitors, even if they weren't familiar with the model of TV and would have leads and tools to do the discharging.

Someone who'd decided to open up a set without any electronics knowledge would be faced with a set of components whose functions weren't obvious. If they started pulling parts out, they might well get a shock, but this probably wouldn't be fatal. Since they're getting the shock from a discharging capacitor, it won't last long. If they went in with both hands, they might get a shock between the hands, and hence across the heart, which could kill them, especially if their heart wasn't in good shape.

If they'd gone in while the set was plugged into mains power, they could get a mains-voltage shock that lasted, but just about everyone knew mains electricity had to be treated with respect by the time TV sets became common. If they went in while the set was switched on, then they're at risk of a long-lasting high-voltage shock, and that is seriously dangerous.

While it's impossible to say nobody got killed doing this, I doubt many deaths happened. I remember old TV sets in the UK having "Danger: High Voltage" or similar warnings on the back. Spreading legends of people getting killed tinkering with TVs would actually have been a good idea.

Sources: Basic electronics knowledge from physics classes and a father who tinkered with electronics but had far more sense than to monkey with TVs.

  • I was a child in the 80's, in Brazil, I have even watched the last Black & White TV set of the family, a small older TV set in the kitchen. They all had warnings "dont open" "call a technician", "risk of shock" etc. That was exactly the tale back then. Charged capacitors, dont fix unless you know what you are doing. Father read about the details and fixed it himself, it was nothing fancy or difficult, but mom got worried everytime. Never heard of actual deaths either, but nobody wants to get a shock.
    – Luiz
    Dec 13, 2022 at 16:05

I was a kid in the 1950s. TV sets were unreliable then, and often the problem was that a tube had burned out. My father would open the back and pick out some likely looking tubes. Then we'd go to the store. It had a tube tester with many different connector types. My father would plug the tubes in, one by one, and the tester would show the tube's health on a dial coded with green/yellow/red. If one or more tubes were bad, he would buy replacements. Then back home, replace the tubes, and try again.

My father was a chemist and savvy technically. He never got a shock.

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    Generally, the tubes were in nice sockets and out in the open (once the cover was off) so one was unlikely to accidentally brush up against a conductor connected to a large capacitor. Similarly, one would not often be opening up a live TV to get a jolt from the flyback transformer (usually you could see the tubes glowing - or not - just fine through the ventilation holes in the chassis).
    – Jon Custer
    Dec 11, 2022 at 19:02

I knew how to remove, test and replace burned out tubes when I was a kid (~12 years old). I opened our TVs, removed tubes, and replaced them myself many times. It's not as dangerous as you think. Although there were capacitors, you would have to touch their terminals or something directly connected to their terminals in order to be shocked, and those things were typically well insulated and protected. The metal chassis and almost all wiring was perfectly safe as long as you unplugged the TV.

Since virtually all hardware stores in that era had self-serve tube testers and sold replacement tubes, it's obvious that it was common for consumers to do this. It was, in fact, routine for the average homeowner.

I've never heard of anyone being killed repairing a TV, or even shocked for that matter. Even in the 1950s, 60s and 70s, manufacturers would have been well aware that building a TV with lethal voltage that could easily be accidentally contacted in a device that consumers regularly serviced themselves would create liability and very bad product PR. And above all, it would also preclude receiving a UL certification in the US, or the comparable certification in other countries. No independent safety certification and you won't be selling your consumer device in any 1st world country.

I think you vastly overestimate the hazards of older TVs.

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    I did the same back in the day. Key phrase: "unplugged the TV" Dec 15, 2022 at 18:04
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    Back in the stone age, I got a shock off an unplugged CRT monitor that hadn't been opened. I pulled the plug out of the socket and my fingers bridged the live and neutral prongs of the plug. I couldn't work out why it had happened until somone told me that it was the capacitors discharging. Dec 16, 2022 at 14:47

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