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Comment by bobbles | Hacker News Reader

>Samsung wants people to go to “qualified” technicians. In a statement, a spokesman said, “The technology found in TVs today is more sophisticated than ever before and often requires a level of expertise and technical proficiency to repair most of these high-quality products.”

>I’ve heard this argument echoed elsewhere in the electronics industry. But the view is not unanimous: Dell, for one, makes repair guides and parts widely available on its site. So do H-P and Lenovo. Are we to believe that repairing a TV is so much more complicated than poking at a laptop?

Opening up a laptop and replacing a part available from the Dell online store is an entirely different scenario to fixing a burnt out TV...

Would the author be arguing the same thing if he'd tried to fix something himself and been zapped in the process?

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> Opening up a laptop and replacing a part available from the Dell online store is an entirely different scenario to fixing a burnt out TV...

Mainly because there isn't a Samsung online store that sells TV parts directly to users (admittedly I'm guessing here), nor did they design the TV to be fixable by semi-competent users, nor did they use interchangeable industry-standard parts, nor do they provide service manuals -- all contrary to the situations with many computers. If you want to argue that it should be this way, go ahead, but you can't merely say "computers and TVs are different", because the TV companies have made it that way by operating differently than the computer companies. A user is just as likely to zap himself on a PC as on a TV, but that didn't stop computers from being a lot more user-serviceable than TVs.

You could just as easily say that the computer companies made it that way.

More to the point, I'm under the impression that you can seriously injure yourself by working on a television, as it has large capacitors (or something, I don't know much about hardware).

I've never heard that said about a laptop, and I have no qualms about changing parts in my computers, while I'm fairly afraid of my televisions.

It makes sense (from a customer focus and engineering perspective) to design items to be easily maintained/repaired. HDTV projection TVs primarily have lamp units that can be easily replaced by end users. My project HDTV was built in 2005 and doesn't have such an easy setup http://gadgets.curiouscatnetwork.com/2015/09/08/homeworx-hdt...

From looking around trying to find what bulbs I am suppose to use I found that pretty much all manufactures seemed to use a simple lamp unit replacement. They all decided it was silly to have such an item not easily replaceable - sadly not mine (mine may well have been the first year of projection HDTVs by Toshiba maybe they took short cuts to get it ready early).

Engineering for sensible repairs is something consumers should expect. Where you draw they line is sometimes hard but some things seem obvious. And that may change over time, not having easy user replaceable batteries seems silly to me. As Apple designed every smaller items and batteries didn't need to be replaced so often making them non-easily-user replaceable became more acceptable in my opinion.

Still it would be better to design for easy and cheap maintenance if possible. Far too often it seems like products are engineered without any thought to servicing or with thinking that seems like planned obsolesces (making it intentionally hard to maintain). Though my guess is it is usually just not thinking about how to design it well for the actual customer use, not them intentionally designing it so users have to buy new ones due to specific design features and company policies shortening the useful life to customers.

The TVs sold in the 1950s and 60s had much bigger caps, and regular people fixed those all the time.

And charged CRTs! And flyback transformers. And people fixed those, and did some calibration when the tv was powered on.

To be fair, pretty much everyone I know who works on high-voltage tube electronics has shocked themselves badly at some point. That stuff can kill and maim.

But the circuits were much simpler... I understand how a rectifier works... I got no idea how a switch mode supply works. And the parts were a lot larger. And the cost per device was a lot greater, too, making paying a repair person a saner choice.

Do LCDs have the high voltage death risk that CRT TVs had?

Some LCD displays are backlit by CCFL lamps, which require HVAC. But the voltage is lower than CRTs need, and there's less current too. There's no HV for LED-backlit displays.

It has mains power in it. 230v in my country which is fairly lethal.

But as i see it we already have the right to fix or own stuff. I mean the warranty will be voided... which i my mind seams fair.

The author does mention unplugging it before starting a repair. I think the mains voltage isn't the issue unless you are feeling really down about the device breaking, so down in fact that you would leave it plugged in before commencing work. Or do I not understand some fundamental of electronics repair that has high voltage on a unplugged device? (genuine question, not an electronics repair shop employee)

IIRC, TVs and similar devices store energy for certain components, so touching one of those can be lethal even if the device is unplugged.

Not a pro either, but I guess the risk, for an unplugged device, is about capacitor: they store current, and if you touch both ends of big one close to the alimentation, you are going to have a nasty shock.

I had first hand experience of that: I repaired a screen, plugged it in to check it, then unplugged it and realized I forgot to cut the ends of a capacitor. When I touched it with a metal tool (luckily, the tool was insolated), there was some serious spark, that I guessed where due to capacitor discharge. Had I used my hand, this would have gone through my skin instead.

Some device use high power capacitors to temporarily store electrical energy and these can remain charged long after the plug is pulled.

You could also accidentally connect a live wire to the metal housing, causing the entire outside of the device to become live when you plug it in after the repair.

Or accidentally cut yourself on the housing or tools, for that matter.

That should not be an option - the device should (and IIRC is required to) be designed with a grounded housing, so if you do actually accidentally connect a live wire, then it would just blow a fuse by that short circuit.

True. So I'd have to make at least two mistakes: let a live wire make contact with the case, and disconnect the ground connection to the case.

Somewhere they've got an exposed AC plug, and there's likely some decently large capacitors nearby. Overall much safer - CRT Tubes themselves had a very high capacitance, and required much more capacitance on the outside to regulate voltage, but I imagine there's still several places you could poke on a modern LCD that would kill you.

Not sure about the author, but I would still be arguing the same thing. No, to a qualified technician there is hardly any difference between swapping capacitors on a TV board and swapping the PSU of a server. The main difference is the tool required.

But more importantly, what kind of patronizing, condescending attitude is that? "This is potentially hazardous, so we're not going to tell you how to do it"? I though most US citizens were against such nanny-state treatment? Or is this suddenly OK because it's not the government doing it, but a foreign corporation?

That "qualified personnel only" comment is partly to protect against people at the low end of the Dunning-Kruger curve.

Isn't it more about charing technicians for Samsug approved training, and a Samsung approved technician certification, and renewal fees each year to keep the listing in some Samsung approved technician list, and fees to access the Samsung approved repository of watermarked manuals?

The kruger-Dunning crowd would just ignore all that and have a go anyway ("How hard can it be?")

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