[HN Gopher] The capacitor that Apple soldered incorrectly at the...
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The capacitor that Apple soldered incorrectly at the factory
Author : zdw
Score : 505 points
Date : 2024-11-27 05:10 UTC (1 days ago)
(HTM) web link (www.downtowndougbrown.com)
(TXT) w3m dump (www.downtowndougbrown.com)
| shiroiushi wrote:
| Apple should be required to do a recall for these motherboards.
| wetpaws wrote:
| For 1993 hardware?
| toast0 wrote:
| If they do a recall, it will say they should be discarded. Sony
| has a recall on all its trinitron tvs made before the end of
| 1990 like this:
|
| https://www.sony.jp/products/overseas/contents/support/infor...
| shiroiushi wrote:
| This shouldn't be allowed at all: if the product was bad all
| along, they should be required to fix it, and shouldn't be
| able to say "well, it's old, so you should just trash it",
| which means they don't suffer any penalty whatsoever.
| duskwuff wrote:
| I don't think that's a reasonable expectation in general,
| and certainly not in this case. The affected TVs were all
| _at least_ 20 years old - that 's well beyond the expected
| useful lifespan of even a modern TV, let alone an older
| model like these. Nor is it clear what Sony could
| reasonably have done to repair them; even by 2010, a lot of
| the parts used in CRT TVs were out of production and
| unavailable.
| shiroiushi wrote:
| Maybe you're too young to remember, but people used to
| keep TVs for much longer periods before HDTV and flat
| panels came out.
|
| Also, these TVs are apparently fire hazards. It doesn't
| matter that they're 20 years old (at the point of the
| "recall" in 2010).
|
| I doubt the parts necessary to fix them were out of
| production; you can get parts for truly ancient
| electronics still. Things like capacitors don't become
| obsolete. The recall doesn't specify exactly which
| component is problematic, but says it's age-related,
| which usually points to capacitors.
| tobr wrote:
| This. I've known a TV that was in more or less daily use
| for over 30 years. Not sure why we stopped expecting that
| from electronics.
| eru wrote:
| Because electronics got so much better so much faster,
| that the vast majority of customers did not want to use
| old hardware.
|
| Especially if customers allowing shorter lifetimes
| allowed companies to lower the prices.
| AnthonyMouse wrote:
| There are many use cases for which a decade-old computer
| is still perfectly serviceable and even where they
| aren't, those computers can be repurposed for the ones
| that are.
|
| Moreover, we're talking about televisions and old Macs.
| TVs with higher resolutions might come out, but lower
| resolution ones continue to be sold new (implying demand
| exists at some price), and then why should anybody want
| to replace a functioning old TV with a newer one of the
| same resolution?
|
| Much older computers continue to be used because they run
| software that newer computers can't without emulation
| (which often introduces bugs) or have older physical
| interfaces compatible with other and often extremely
| expensive older hardware.
|
| If people actually wanted to replace their hardware
| instead of fixing it then they'd not be complaining about
| the inability to fix it.
| shiroiushi wrote:
| >There are many use cases for which a decade-old computer
| is still perfectly serviceable and even where they
| aren't, those computers can be repurposed for the ones
| that are.
|
| It depends. Older computers usually guzzle power,
| especially if you look at the absolutely awful Pentium4
| systems. You're probably better off getting a RasPi or
| something, depending on what exactly you're trying to do.
| Newer systems have gotten much better with energy
| efficiency, so they'll pay for themselves quickly through
| lower electricity bills.
|
| >TVs with higher resolutions might come out, but lower
| resolution ones continue to be sold new (implying demand
| exists at some price)
|
| We're already seeing a limit here. 8k TVs are here now,
| but not very popular. There's almost no media in that
| resolution, and people can't tell the difference from 4k.
|
| For a while, this wasn't the case: people were upgrading
| from 480 to 720 to 1080 and now to 4k.
|
| >and then why should anybody want to replace a
| functioning old TV with a newer one of the same
| resolution?
|
| They probably don't; if they're upgrading, they're
| getting a higher resolution (lots of 1080 screens still
| out there), or they're getting a bigger screen. It's
| possible they might want newer smart TV features too:
| older sets probably have support dropped and don't
| support the latest streaming services, though usually you
| can just get an add-on device that plugs into the HDMI
| port so this is probably less of a factor.
| ahoka wrote:
| A decade old CPU would be a Haswell, not a Pentium 4.
| aero_code wrote:
| > Older computers usually guzzle power, especially if you
| look at the absolutely awful Pentium4 systems.
|
| https://en.wikipedia.org/wiki/List_of_Intel_Pentium_4_pro
| ces...
|
| The Northwood chips were 50 to 70 W. HT chips and later
| Prescott chips were more 80 to 90 W. Even the highest
| chips I see on the page are only 115 W.
|
| But modern chips can use way more power than Pentium 4
| chips:
|
| https://en.wikipedia.org/wiki/Raptor_Lake
|
| The i5-14600K has a base TDP of 125 W and turbo TDP of
| 181 W, and the high-end i9-14900KS is 150 W base/253 W
| turbo. For example, when encoding video, the mid-range
| 14600K pulls 146 W:
| https://www.tomshardware.com/news/intel-
| core-i9-14900k-cpu-r...
|
| More recent processors can do more with the same power
| than older processors, but I think for the most part that
| doesn't matter. Most people don't keep their processor at
| 100% usage a lot anyway.
| shiroiushi wrote:
| As I said in a sister comment here, you can't compare
| CPUs by TDP. No one runs their CPU flat-out all the time
| on a PC. Idle power is the important metric.
| AnthonyMouse wrote:
| > Older computers usually guzzle power, especially if you
| look at the absolutely awful Pentium4 systems.
|
| Even many Pentium 4-based systems would idle around 30
| watts and peak at a little over 100, which is on par with
| a lot of modern desktops, and there were lower and higher
| power systems both then and now. The top end Pentium 4
| had a TDP of 115W vs. 170W for the current top end Ryzen
| 9000 and even worse for current Intel. Midrange then and
| now was ~65W. Also, the Pentium 4 is _twenty two_ years
| old.
|
| And the Pentium 4 in particular was an atypically
| inefficient CPU. The contemporaneous Pentium M was so
| much better that Intel soon after dumped the P4 in favor
| of a desktop CPU based on that (Core 2 Duo).
|
| Moreover, you're not going to be worried about electric
| bills for older phones or tablets with <5W CPUs, so why
| do those go out of support so fast? Plenty of people
| whose most demanding mobile workload is GPS navigation,
| which has been available since before the turn of the
| century and widely available for nearly two decades.
|
| > For a while, this wasn't the case: people were
| upgrading from 480 to 720 to 1080 and now to 4k.
|
| Some people. Plenty of others who don't even care about
| 4k, and then why would they want to needlessly replace
| their existing TV?
|
| > They probably don't; if they're upgrading, they're
| getting a higher resolution (lots of 1080 screens still
| out there), or they're getting a bigger screen.
|
| That's the point. 1080p TVs and even some 720p TVs are
| still sold new, so anyone buying one isn't upgrading and
| has no real reason to want to replace their existing
| device unless it e.g. has a design flaw that causes it to
| catch fire. In which case they should do a proper recall.
| shiroiushi wrote:
| >The top end Pentium 4 had a TDP of 115W vs. 170W for the
| current top end Ryzen 9000 and even worse for current
| Intel.
|
| You can't compare CPUs based on TDP; it's an almost
| entirely useless measurement. The only thing it's good
| for is making sure you have a sufficient heatsink and
| cooling system, because it tells you only the peak power
| consumption of the chip. No one runs their CPUs flat-out
| all the time unless it's some kind of data center or
| something; we're talking about PCs here.
|
| What's important is idle CPU power consumption, and
| that's significantly better these days.
|
| >older phones or tablets with <5W CPUs, so why do those
| go out of support so fast?
|
| That's an entirely different situation because of the
| closed and vendor-controlled nature of those systems.
| They're not PCs; they're basically appliances. It's a
| shitty situation, but there's not much people can do
| about it, though many have tried (CyanogenMod,
| GrapheneOS, etc.).
|
| >Plenty of others who don't even care about 4k
|
| Not everyone cares about 4k, it's true (personally I like
| it but it's not _that_ much better than 1080p). But if
| you can 't tell the difference between 1080p and an NTSC
| TV, you're blind.
|
| >1080p TVs and even some 720p TVs are still sold new
|
| Yes, as I said before, we're seeing diminishing returns.
| (Or should I say "diminishing discernable improvements"?)
|
| Also, the 720p stuff is only in very small (relatively)
| screens. You're not going to find a 75" TV with 720p or
| even 1080p; those are all 4k. The low-res stuff is
| relegated to very small budget models where it's really
| pointless to have such high resolution.
| eru wrote:
| For most videos, the difference between 1080p and 4k
| ain't that large.
|
| But for certain video games on a large screen, I can
| definitely tell the different between 1080p and 4k.
| Especially strategy games that present a lot of
| information.
|
| Btw, as far as I can tell modern screens use
| significantly less power, especially per unit of area,
| than the CRTs of old; even if that CRT is still perfectly
| functional.
| AnthonyMouse wrote:
| > What's important is idle CPU power consumption, and
| that's significantly better these days.
|
| It isn't. You can find both ancient and modern PCs that
| idle anywhere in the range from 10 to 30 watts, and
| pathological cases for both where the idle is >100W. Some
| of the newer ones can even get pretty close to zero, but
| the difference between zero and 30 watts for something
| you're leaving on eight hours a day at $0.25/kWh is
| ~$22/year. Which is less than the interest you'd get from
| sticking the $600 cost of a new PC in a 5% CD.
|
| And many of the new ones are still 30 watts or more at
| idle.
|
| > That's an entirely different situation because of the
| closed and vendor-controlled nature of those systems.
|
| It's a _worse_ situation, but if the complaint is that
| they abandon their customers long before the customer
| wants to stop using the device, they certainly match the
| criteria.
|
| > But if you can't tell the difference between 1080p and
| an NTSC TV, you're blind.
|
| Being able to discern a difference and caring about it
| are two different things. If your use for a TV is to
| watch the news and play 90s video games then the
| resolution of the talking heads doesn't matter and the
| classic games aren't in 1080p anyway.
|
| > The low-res stuff is relegated to very small budget
| models where it's really pointless to have such high
| resolution.
|
| Which is the point. If you have an old 30" TV and no
| space for a 72" TV, you do not need a new 30" TV.
| shiroiushi wrote:
| >Not sure why we stopped expecting that from electronics.
|
| For TVs specifically, the technology changed a lot. For a
| long time, everyone was stuck on the NTSC standard, which
| didn't change much. At first, everyone had B&W TVs, so
| once you had one, there was no reason to change. Then
| color TV came out, so suddenly people wanted those. After
| that, again no reason to change for a long time. Later,
| they got remote controls, so sometimes people would want
| one of those, or maybe a bigger screen, but generally a
| working color TV was good enough. Because TVs were glass
| CRTs, bigger screens cost a lot more than smaller ones,
| and there wasn't much change in cost here for a long
| time.
|
| Then HDTV came out and now people wanted those, first in
| 720p, and later in 1080i/p. And flat screens came too, so
| people wanted those too. So in a relatively short amount
| of time, people went from old-style NTSC CRTs to seeing
| rapid improvements in resolution (480p->720p->1080->4k),
| screen size (going from ~20" to 3x", 4x", 5x", 6x", now
| up to 85"), and also display/color quality (LCD, plasma,
| QLED, OLED), so there were valid reasons to upgrade. The
| media quality (I hate the word "content") changed too,
| with programs being shot in HD, and lately 4k/HDR, so the
| difference was quite noticeable to viewers.
|
| Before long, the improvements are going to slow or stop.
| They already have 8k screens, but no one buys them
| because there's no media for them and they can't really
| see the difference from 4k. Even 1080p media looks great
| on a 4k screen with upscaling, and not that much
| different from 4k. The human eye is only capable of so
| much, so we're seeing diminishing returns.
|
| So I predict that this rapid upgrade cycle might be
| slowing, and probably stopping before long with the
| coming economic crash and Great Depression of 2025. The
| main driver of new TV sales will be people's old TVs
| dying from component failure.
| bregma wrote:
| > The human eye is only capable of so much, so we're
| seeing diminishing returns.
|
| Or not seeing diminishing returns. Which is the point.
| Someone wrote:
| > At first, everyone had B&W TVs, so once you had one,
| there was no reason to change
|
| Televisions improved over time:
|
| - screens got flatter
|
| - screens got larger
|
| - image quality improved
|
| - image contrast increased (people used to close their
| curtains to watch tv)
|
| - televisions got preset channels
| kstrauser wrote:
| Great points. The TV I have today is approaching my
| platonic ideal screen. It's as big as it can get without
| having to continually look around to see the whole
| screen. Sit in the first row of a movie theater to
| understand how that can be a bad thing. The pixels are
| smaller than I can see, it has great dynamic range, and
| the colors can be as saturated as I'd ever want. There's
| not much that can be improved on it as a traditional
| flatscreen video monitor.
| blitzar wrote:
| > Not sure why we stopped expecting that from
| electronics.
|
| Last years model only does 4k, my eyes need 8k
| xattt wrote:
| 32K ought to be enough for anybody.
| blitzar wrote:
| 32K is going to look so lifeless and dull after you try
| 64k.
| xattt wrote:
| When will the pixels start to approach erythrocyte-level
| density like on the Vision Pro?
|
| edit: Anywhere between 208K to 277K.
| bloak wrote:
| My experience of ancient CRT devices is that the display
| gets gradually dimmer. I once had a TV that was only
| really usable after dark -- but that's the only time I
| wanted to use it anyway -- and a huge Sun monitor that
| was only just about readable in total darkness, but we
| kept it because we also had a Sun server that we didn't
| know how to connect to any other monitor and we were
| worried that one day we wouldn't be able to SSH to it,
| but in fact the server never once failed.
| robocat wrote:
| > daily use for over 30 years
|
| However that doesn't imply TVs were that reliable.
|
| Before the 90s TV repairman was a regular job, and TVs
| often needed occasional expensive servicing. I remember a
| local TV repair place in the 90s which serviced "old"
| TVs.
| nuancebydefault wrote:
| Suppose they would recall all the old tv's with known
| faults, can those be fixed to become conform to (today's)
| quality and safety standards, while being full of old
| components with characteristics beyond original
| tolerances?
| kbelder wrote:
| > that's well beyond the expected useful lifespan of even
| a modern TV, let alone an older model like these
|
| A modern TV may have an expected lifespan of five years.
| TVs from several decades ago had lifespans of... several
| decades. Quality has plummeted in that market.
| eru wrote:
| Only one metric of 'quality' has plummeted.
|
| A rock lasts billions of years, but its quality as a TV
| is rather questionable.
| azinman2 wrote:
| 5 years? Is that really true? I'm currently using an LG
| from 2017 and cannot imagine needing to change it. I
| would be shocked if it stopped working.
| tverbeure wrote:
| I don't think it is true at all.
|
| There's nothing inside today's monitors or TVs that can't
| run for at least 10 years. Our main TV, 42" 720p LCD, is
| from 2008, and I have monitors that are just as old.
| Supernaut wrote:
| Yep. My TV, a 42" Panasonic plasma, dates from 2009 and
| is still working perfectly. I haven't replaced it,
| because why would I?
| rvense wrote:
| But when it does, it will probably be the capacitors in
| the power supply that have dried out.
| verzali wrote:
| Is that really the case? Because if so, it seems like
| simply replacing the capacitors would save a lot of waste
| and unnecessary purchases of new TVs...
| rvense wrote:
| This is a very common fault, yes. Power supply issues in
| general. It is also not uncommon for people to replace
| e.g. Wifi routers because the wall warts fail.
|
| It comes down to a few people don't knowing a lot about
| it - and I'm not blaming anyone for that, we all have our
| interests and most people have more than enough to do
| already to worry about what goes on inside their stuff.
|
| Also, electronics are, to a lot of people in a lot of
| places, so cheap that they would rather just curse a
| little and buy a new thing, instead of bothering with
| taking the thing to a shop. And of course a few hours of
| skilled labour in a big city in the west might also be
| almost as expensive as making a whole new TV in a factory
| in Asia plus shipping, so it might not even make economic
| sense.
| quesera wrote:
| > _And of course a few hours of skilled labour in a big
| city ..._
|
| In many/most places, these repair shops don't even exist
| any more, because the products have gotten too
| complicated/integrated/parts-unavailable, and the
| economics are nonsensical.
| xxs wrote:
| Electrolytic capacitors are not solid state and likely #1
| failure mode for most electronics. There are options for
| better (e.g. Al polymer) capacitors that are rather
| expensive - overall good capacitors are 'expensive', e.g.
| more than a dollar a piece in some cases.
|
| The 2nd most common failure mode gotta be the mlcc (multi
| layer ceramic capacitor) cracks/shorts.
| nuancebydefault wrote:
| How can I even know which capacitor is faulty?
| xxs wrote:
| That would require some experience, yet the most common
| visual clue would be 'bulging'. There are some ways to
| measure ESR w/o desoldering but they won't be reliable at
| all times.
|
| Measuring voltages, peak to peak, is a bit more work.
| toast0 wrote:
| If your model was popular, there's likely a recap kit for
| its power supply. It usually makes senss to swap all the
| capacitors in the kit, unless the kit instructions say
| otherwise.
|
| You can look for physical signs of degredation (bulgy,
| leaky, discolored), but to really test a capacitor for
| capacititance, you need to take it out of the circuit, at
| which point, you may as well put a new, high quality
| capacitor in.
|
| The OEM capacitors may likely have a just right voltage
| rating, a new one with a higher voltage rating (and same
| capacitance, compatible type) may last longer in cirucit
| as well.
| xxs wrote:
| > new one with a higher voltage rating (and same
| capacitance, compatible type) may last longer in cirucit
| as well.
|
| That's not necessarily true, higher voltage rating equals
| higher ESR which means more heat.
| alias_neo wrote:
| I have an LG OLED from 2017. It started getting really
| bad screen burn/pixel degredation just after the 6 year
| mark (6 year warranty), I did a quick search on Youtube,
| and lo-and-behold, a whole bunch of other people, with
| the same model, started having the same screen burn-in
| issues at the same age!
|
| It covers the middle third of the screen, top to bottom,
| and the entire bottom 1/4 of the screen with some odd
| spots as well, it's really distracting and essentially
| makes the TV useless (to me).
| shiroiushi wrote:
| OLED screens are known for having burn-in problems like
| this. LCDs don't, though they probably have issues with
| backlights becoming dim with age.
| cmgbhm wrote:
| I have an LG about that vintage and it's starting to
| black out when doing 4K content. All components before it
| switched out and up to date in firmware. Reatarting
| works, sometimes all day, sometimes 1 minute.
|
| My other TV about the same vintage is starting to have
| stuck pixels in the corner.
|
| Modern failure modes aren't nearly as graceful.
| Peanuts99 wrote:
| A TV used to cost a few weeks pay and now you can get a
| TV for the equivalent of a few hours pay. There just
| isn't much of a market for a $3000+ TV.
| xxs wrote:
| Few usually means 3-5 or so, a half decent TV would be at
| least half a grand. That's rather high hourly pay rate.
| toast0 wrote:
| Explain to me why this tv for $100 [1] isn't perfectly
| suitable to replace a 2008 40" 1080p Samsung LCD with
| florescent backlight that 2was a deal at $1000. Yeah, you
| could get something bigger and better. Yes, price
| comparison on a sale week is a bit unfair.
|
| [1] https://www.bestbuy.com/site/tcl-40-class-s3-s-class-
| 1080p-f...
| xxs wrote:
| FYI: bestbuy is unavailable outside the US (the site I
| mean), or likely NA.
| bee_rider wrote:
| It is a legitimate business decision, to sell things that
| last less than 20 years. Fine, I think it is lame, but it
| is their choice.
|
| But, we shouldn't let companies get away with selling
| products that catch fire after working fine for 20 years.
| InsideOutSanta wrote:
| "that's well beyond the expected useful lifespan of even
| a modern TV, let alone an older model like these"
|
| People still run these Trinitron TVs to this day.
| PittleyDunkin wrote:
| > that's well beyond the expected useful lifespan of even
| a modern TV
|
| What? That's nuts. Why bother buying a tv if you're
| immediately going to throw it in the trash
| tengbretson wrote:
| My radial arm saw ended up getting a product recall for
| simply being too difficult for the average consumer to use
| safely. The "recall" amounted to them sending you
| instructions to cut off a critical power cord and mail it
| in to them, and they send you a $50 check.
| bigstrat2003 wrote:
| That is completely unreasonable. Companies can't be
| expected to take in and repair devices that old.
| Throw8394045 wrote:
| They don't do recalls even on modern hardware. But soldering
| hacks are no longer possible, all parts are serialized.
|
| Louis Rossmann made many videos on this.
| shiroiushi wrote:
| What are you talking about? Capacitor technology hasn't
| changed substantially in decades, and it's just as possible
| to change caps with a soldering iron now as it was 20 years
| ago. I have no idea what you mean by "serialized".
| fragmede wrote:
| not capacitors, but more advanced components, like the
| camera, have serial numbers embedded in them, and the
| serial number needs to match, otherwise it won't accept the
| component. Components off a stolen device are put on a list
| and won't work in admirer another phone, so stolen phones
| aren't even worth anything for parts, driving down the
| market for stolen phones. It also makes the job of repair
| shops harder, which is collateral damage in Apple's eyes,
| but is very much material for anyone running a repair shop.
| shiroiushi wrote:
| I see. Yes, that is a big problem for component swapping.
| I was just thinking of electronics with old/faulty caps;
| those will still be repairable.
| pkolaczk wrote:
| Doesn't Apple offer a way to re-pair components if they
| are genuine and not stolen (unregistered from the
| previous AppleId)?
| fragmede wrote:
| and Apple will very happily charge you for that privilege
| jajko wrote:
| TBH for such a critical piece of our modern lives, I
| would be more than fine to pay extra to be 100% sure I am
| getting original parts, put in professionally and in
| secure manner re my personal data. I wish ie Samsung had
| such service where I live.
|
| We anyway talk about expensive premium phones to start
| with, so relatively expensive after-warranty service is
| not shocking.
|
| This may actually eventually sway me into apple camp.
| This and what seems like much better theft
| discouragement.
| raxxorraxor wrote:
| I don't. Such mechanisms also disqualify 3rd party
| replacements. It is just a wasteful solution. Not that
| any smartphone would qualify as decent here.
|
| But as a customer it will overall be more expensive for
| you.
| jajko wrote:
| There are things in life where amount paid is far from
| top priority, and phone is one these days. With sums we
| talk about, I just don't care anymore, and Samsung I have
| now is even more expensive and more wasteful.
|
| Re wastefulness - a decent laptop causes 10x more
| pollution to manufacture than phone. Desktop PC 10x that.
| TVs. Cars. Clothing. Phones are very much down a very
| long line of higher priority targets for eco friendly
| approach.
| raxxorraxor wrote:
| I personally don't care much about $ but many probably
| are. I care that the manufacturers don't work with user
| orientation in mind and instead take advantage of them. I
| don't want to be a customer here. Replacement parts are
| possible and we maybe need regulation on that front to
| reduce waste. I doesn't matter if other devices are
| worse.
|
| Other example have a longer shelf life or are at least
| repairable without being tied to a manufacturer.
| Notebooks have similar problems and the critique can be
| transferred here in a similar way. I see synergies in
| possible rules here of course.
| ethernot wrote:
| The only reason this is an issue for repair shops is they
| can't sell you recycled stolen parts at bottom of market
| prices for a sky high mark up. On top of that the "non
| genuine parts", some of which really are utterly dire,
| show up in the OS as being not genuine parts. Buying
| genuine parts, which are available from Apple, eats into
| the margins. There is very little honour in the repair
| market, despite the makeup applied to it by a couple of
| prominent youtubers and organisations.
|
| The amount of horror stories I've seen over the years
| from independent repairers is just terrible. Just last
| year a friend had a screen hot snotted back on their
| Galaxy.
| liontwist wrote:
| > they can't sell you recycled stolen parts at bottom of
| market prices for a sky high mark up
|
| What represents a more efficient economy. The one where
| broken phones get reused for parts or the one where you
| have to throw them away?
| ethernot wrote:
| The economy that isn't backed with criminal activity and
| loss for customers.
| moooo99 wrote:
| > The only reason this is an issue for repair shops is
| they can't sell you recycled stolen parts at bottom of
| market prices for a sky high mark up.
|
| This is just incredibly dishonest framing and completely
| ignoring what the right to repair and third party repair
| shop issue is all about.
|
| > Buying genuine parts, which are available from Apple,
|
| It is not a margin problem, it is an availability
| problem. Apple does not allow third party repair shops to
| stock common parts, such as batteries or displays for
| popular iPhones. This is only possible when providing the
| devices serial numbers. This effectively prevents third
| party repair shops from competing with Apple or Apple
| authorized service providers because they have
| artificially inflated lead times.
|
| Becoming Apple authorized isn't an option for actual
| repair shops because that would effectively disallow them
| from doing actual repairs when possible, rather than
| playing Dr. Part Swap. Everything what Apple does in the
| repair space essentially boils down to them doing
| everything they can to avoid having competition in the
| repair space.
|
| > eats into the margins
|
| Replacing a 45ct voltage regulator on a mainboard is
| cheaper than replacing the entire mainboard with
| everything soldered on is cheaper, but doesn't allow for
| very nice margins.
|
| > There is very little honour in the repair market
|
| There is very little honour in any market. Honour does
| not get rewarded nowadays, people are in <insert market>
| to make money, if you're lucky they still take a little
| pride in their work. If a repair shop offers good service
| or not should be up to the consumer to determine, not up
| to Apple (or any electriconics manufacturer that employs
| the same tactics).
|
| > makeup applied to it by a couple of prominent youtubers
| and organisations.
|
| That is called marketing, that's what Apple does also
| pretty good. They're also lying when they say they are
| environmentally conscious while they also have their
| genius bar employees recommend an entirely new screen
| assembly on a MacBook just because a backlight cable came
| loose.
|
| > The amount of horror stories I've seen over the years
| from independent repairers is just terrible. J
|
| The amount of horror stories I have experienced with
| Apple is no joke either. Apple is always taking the
| sledgehammer approach with their repairs. I've had the
| pleasure myself to deal with Apple repairs once for my
| old 2019 MBP. It wouldn't take a charge anymore, went to
| the Genius Bar and received a quote for a new mainboard
| costing well over 1000 EUR. Being familiar with some of
| the more technical videos of Rossmann etc, I found one
| electronics repair store that actually does board level
| stuff and got it fixed for a fraction of the price (iirc
| it was ~200 EUR).
| cosmic_cheese wrote:
| Even if Apple has room for improvement here, I think it's
| still worth it to try to curb the market for stolen
| parts, because that's going to exist even if Apple sold
| spare parts in bulk at-cost simply because there exist
| unscrupulous repair shops that have no qualms with
| charging you OEM part prices while using gray market
| parts that cost a fraction as much on eBay, Aliexpress,
| etc.
|
| For instance, maybe Apple could supply parts in bulk to
| repair shops but require registration of those parts
| prior to usage. The repaired iPhone would function
| regardless but loudly alert the user that unregistered
| parts were used to repair it. Gray market parts naturally
| aren't going to be able to be registered (either due to
| serial not existing in their system or having been parted
| out from stolen devices), and thus the user is given some
| level of assurance that they're not paid for questionable
| repair services.
| bigstrat2003 wrote:
| If you think Apple's part pairing policy has anything to
| do with consumer benefit, I have a bridge in Arizona to
| sell you.
| raxxorraxor wrote:
| It is not about stolen phones, it is about monetization
| of customer services. If stealing phones was legal, job
| description for procurement/purchase departments would
| look differently as well.
| codewiz wrote:
| Commodore had _3_ capacitors mounted backwards on the A3640, the
| CPU board of the Amiga 4000 with 68040 processors:
| https://youtu.be/zhUpcBpJUzg?si=j6UFmIJzoC-UDS6u&t=945
|
| Also mentioned here: https://amiga.resource.cx/exp/a3640
| bogantech wrote:
| Classic Commodore Quality :P
|
| They also had backwards caps on the CD32 and A4000
| krige wrote:
| Commodore just kept doing this. Just listing shoddy
| craftsmanship would take forever, and then we get to
| intentional bad decisions, like giving the A1200 a power supply
| that's both defective (capacitors ofc) and barely enough to
| support the basic configuration with no expansions, which is
| extra funny because PSUs used with weaker models (A500) had
| greater output...
| bbarnett wrote:
| The number of used a500 power supplies I sold to customers
| when I upgraded their a1200 with a GVP 030 board + RAM...
| kstrauser wrote:
| This was the hardware patch I had to install to use a
| CyberstormPPC:
| https://powerup.amigaworld.de/index.php?lang=en&page=29
| rwmj wrote:
| ZX Spectrum +2 shipped with _transistors_ backwards:
| https://www.bitwrangler.uk/2022/07/23/zx-spectrum-2-video-fi...
| This even caused visible artifacts on the display, which was
| apparently not enough for the problem to be noticed at the
| factory.
| extraduder_ire wrote:
| I think Clive Sinclair was notorious for wanting products to
| be brought to market quickly, with pretty aggressive feature
| sets. They very well may have noticed it at the factory, but
| didn't want to do a fix because it was technically
| functional.
| lproven wrote:
| The +2 was an Amstrad product, not designed or built by
| Sinclair, though.
| ethbr1 wrote:
| Well, today I learned to install one capacitor in reverse
| orientation on the PCB on a 34 year old computer...
|
| Definitely starting Wednesday off productively.
| xeyownt wrote:
| At least you made my Wednesday ;-)
| phire wrote:
| I actually have an LC III in storage, so I might actually be
| able to make use of this article.
|
| I think this will allow me to classify today as productive.
| InsideOutSanta wrote:
| Yeah, I have a Performa 450, which I believe is the exact
| same computer sold under a different name. So this is
| definitely important to know. I can go back to bed now, my
| job for today is done.
| grujicd wrote:
| Well, until today I didn't even know capacitor can have
| orientation! So more productive Wednesday than yours. In entry
| level electronics class I had decades ago it was always treated
| as a component that works the same way no matter in which
| direction the current flows.
| fredoralive wrote:
| There are polarised and unpolarised capacitors. Stuff like
| basic decoupling capacitors tend to be unpolarised.
| Filligree wrote:
| Ceramic capacitors don't have polarity. Electrolytic ones do.
| Thing is, electrolytic capacitors have far higher capacitance
| for their size -- though also higher resistance.
|
| It's something to check, but the polar ones should be clearly
| marked as such.
| magic_smoke_ee wrote:
| Electrolytic capacitors are kinda like lead-acid batteries
| in that they are polarized through manufacturing processes.
| A voltage is applied in the factory to anodize the anode
| with a thin oxide layer. For fun, I think it would be
| possible to buy a quality low voltage cap and reverse the
| polarity of it in-situ which would remove the anodization
| from the new cathode and deposit a new layer on the new
| anode (former cathode) hopefully without over-pressurizing
| it to bursting, albeit with much less anticipated lifespan.
|
| PSA: Electrolytic capacitors have a rough lifespan of 10
| years. Any much older than that need to be checked out-of-
| circuit for ESR and then capacitance. Also, tantalums
| (historically) suck(ed). [0] Quality audio equipment from
| the 80's like a/d/s/ car amps used only ceramic caps and
| other over-engineered passives, and have the potential (pun
| intended) to basically last forever.
|
| 0. https://www.eevblog.com/forum/projects/whenwhy-(not)-to-
| use-...
| kevindamm wrote:
| Or much shorter, around two years, if it was part of the
| Capacitor Plague.
|
| https://en.wikipedia.org/wiki/Capacitor_plague#Premature_
| fai... The normal lifespan of a non-
| solid electrolytic capacitor of consumer quality,
| typically rated at 2000 h/85 degC and operating at 40
| degC, is roughly 6 years. It can be more than 10 years
| for a 1000 h/105 degC capacitor operating at 40 degC.
| Electrolytic capacitors that operate at a lower
| temperature can have a considerably longer lifespan. ...
| The life of an electrolytic capacitor with defective
| electrolyte can be as little as two years.
| Workaccount2 wrote:
| This is also why so many LED bulbs are shit, lots of heat
| in a small space full of electrolytic caps.
| magic_smoke_ee wrote:
| Intentional planned consumption/obsolescence by design.
| This class of problem is where under-regulation and lack
| of standards benefits only sellers and cheats buyers. PS:
| Also, Amazon should be required to test all of the
| electronic, safety, and food products on its site such
| that they can prove safety and standards conformance.
| Filligree wrote:
| That, and customers insisting on preexisting form
| factors. Fitting the electronics _and LEDs_ into the
| space of a traditional lightbulb comes with compromises,
| such as not having proper heat dissipation on either.
| BlueTemplar wrote:
| Yeah, you would think they would be two separate devices
| by now...
| Workaccount2 wrote:
| I am assuming you are an ee (like myself)...I have never
| designed a product with a built in expiration, nor have I
| ever seen any app notes or write ups on the engineering
| of it - something engineers love to do.
|
| What I have seen done is cheaping out on parts in order
| to get the price as low as possible, because customers
| shop primarily on price.
|
| Not to lash out, but it kind of hits a nerve for me,
| because people think we design products to purposely
| fail. Hell no, we try really hard to do the opposite, but
| everyone just loves to buy the cheapest shit.
|
| The $25 LED bulb that will last for eternity will rot on
| the shelf next to the $3 bulb that will probably be dead
| in 6 months. And one more "they build these things to
| fail" complaint will be posted online.
| belval wrote:
| To be fair this is hardly limited to EE and is the issue
| with the race to the bottom in all product categories.
| Make long-lasting high-quality 100$ pants? People prefer
| spending 10$ on Shein.
|
| Additionally, the issue is that as a consumer, it's not
| easy to differentiate between quality markup and greedy
| markup. I don't see the cap manufacturer on the box so
| the 25$ light bulb might last 10 years or it might last 6
| months just like the 3$ one. At least with the 3$ one I
| can come back and buy another...
| robertlagrant wrote:
| > Make long-lasting high-quality 100$ pants? People
| prefer spending 10$ on Shein.
|
| This is just fashion, right? As something becomes
| commoditised, it starts to become subject to fashion,
| which means cheap and looks fashionable is more important
| than durability. So you can buy one every year and keep
| up, and throw away the old one.
| magic_smoke_ee wrote:
| I seriously doubt it's ever a deliberate conspiracy in
| engineering apart from shenanigans like what happened at
| VW, but it's net effect of product managers, accountants,
| and contract manufacturers who modify PCBs and BOMs after
| it's passed off to them to save money on retail products.
| And so it's likely unintentional with negligence, but it
| benefits the company. Except for some Samsung appliances
| made ~ 2010-2014 which seemed to fail just after their
| warranties expired. I suspect highly-optimized designs
| for "consumables" like incandescent lightbulbs and parts
| for cars use data to tweak design life, more often than
| not, in their favor. And, with the pressures of
| multinational oligopolies and BlackRock/Vanguard/State
| Street.. there is little incentive to invest $100M into a
| moderately-superior incandescent lightbulb using
| yesterday's technology that lasts 100kh and 5k cycles and
| sells for $1 more than the next one. Maybe if we (perhaps
| a science/engineering nonprofit thinktank that spanned
| the world and gave away designs and manufacturing
| expertise) had quasi-communism for R&D, we could have
| very nice things.
|
| It's not my fault if other people are too dumb to
| comprehend TCO because I would buy the $25 bulb if it had
| a 30 year warranty.
| kube-system wrote:
| > Except for some Samsung appliances made ~ 2010-2014
| which seemed to fail just after their warranties expired.
|
| And? That just sounds like they have good engineers. If
| you are designing a machine, you have an target lifetime.
| You'd obviously want the product to last through the
| warranty period, because warranty claims are a cost to
| the company.
|
| Every choice of a component affects lifetime. Designers
| of mass-market products can't just use premium components
| everywhere -- the mass market will not pay steep premiums
| for otherwise equivalent products.
|
| Value engineering and planned obsolescence are not the
| same thing, but they are often confused.
|
| That being said, Samsung appliances suck and I hate them.
| Mine failed within warranty several times.
|
| > And, with the pressures of multinational oligopolies
| and BlackRock/Vanguard/State Street.. there is little
| incentive to invest $100M into a moderately-superior
| incandescent lightbulb using yesterday's technology that
| lasts 100kh and 5k cycles and sells for $1 more than the
| next one.
|
| It isn't that. It's pressure _at the shelf_ that does it.
| Consumers behavior simply does not reward equivalent-
| feature products with premium components that claim (true
| or not) to have a longer lifespan. Unfortunately, they
| _will_ buy based on their uninformed sense of quality
| first.
|
| If you release a light bulb that is identical to the best
| selling one on the shelf, but claims 10x lifespan, your
| competitor will do something like gluing a weight in
| theirs, putting some marketing BS on the box, and will
| put you out of business. Consumers just don't pick
| products based on _actual_ quality.
| magic_smoke_ee wrote:
| You're making a pretty awkward value judgement about what
| a "good" engineer is, but you're describing an unethical
| one with a bizword like "value engineering". I realize
| ethics are no longer understood by much of Western
| society because the culture teaches transactionality,
| worships trickle-down economics and greed, and
| hyperindividualism.
|
| > It isn't that. It's pressure at the shelf that does it.
| Consumers behavior simply does not reward equivalent-
| feature products with premium components that claim (true
| or not) to have a longer lifespan. Unfortunately, they
| will buy based on their uninformed sense of quality
| first.
|
| This is a failure of marketing and buzz of the sales
| channel(s) and manufacturers to educate properly, not the
| failure of the customer.
| kube-system wrote:
| A good engineer is one that has a job, doesn't put their
| employer out of business, and produces work that fulfills
| the requirements they're given.
|
| _Many people think_ there 's some unethical conspiracy
| going on, and consumers actually want a product that
| lasts a long time, but companies are refusing to give it
| to them. But this is projection of individual preferences
| on to the market as a whole. Consumers want cheap shit
| that is in fashion, and their buying preferences prove
| this time and again. Maybe _you want_ a 50 year old
| toaster in your kitchen, other people are buying products
| based on other factors.
|
| If consumers really wanted to pay a premium for high
| duty-cycle equipment with premium lifespans, they can
| already do that by buying commercial grade equipment. But
| they don't.
|
| If you are familiar with the history of home appliances,
| you'd probably come to appreciate the phrase 'value
| engineering'. Even poor people can afford basic electric
| appliances now because of the ingenuous ways that
| engineers have designed surprisingly usable appliances
| out of very minimal and efficient designs.
|
| If you look at ads for electric toasters 100 years ago,
| you'd see they cost over $300 in today's money adjusted
| for inflation. Thank god for value engineering.
| harimau777 wrote:
| A good engineer provides value to society. If they
| fulfill requirements that are bad for others then they
| are not good engineers.
|
| I seems to me that there is also a social dynamic to
| things. If consumer grade products become a race to the
| bottom then it is going to become more difficult for
| regular people to purchase products which aren't low
| quality. There's also a degree to which society (e.g. in
| the form of government policy, cost of living
| adjustments, etc.) factors in differences in prices.
| kube-system wrote:
| The fact that poor people can now afford to own some
| household appliances isn't a huge value to society?
|
| It completely changed the way our societies operate. I
| think it is a good thing that people have the option to
| buy crappy washing machines, rather than being forced to
| use the washboard and bucket my grandmother used. Yeah,
| they sometimes do develop a bad belt, or the timer
| mechanism might fail. But it beats being unwillingly
| forced into homemaking as a career.
|
| The world only has so much wealth to go around, and that
| isn't the moral quandary of the engineer picking an item
| on a BOM on Tuesday morning to fix. If anything,
| squeezing a few more pennies out of that BOM is going to
| lift some people at the fringes out of poverty. At the
| opposite end of the product value equation, every unused
| and functional component in every product that is no
| longer in service, is wealth that is wasted that could
| have been spent elsewhere.
| Dylan16807 wrote:
| > If anything, squeezing a few more pennies out of that
| BOM is going to lift some people at the fringes out of
| poverty.
|
| If it squeezes a small but solid chunk out of product
| lifetime too, then it's also likely to harm people on the
| fringes. If they can buy it with one less month of
| savings, but then it breaks a couple months earlier,
| they're probably worse off. (For actual pennies divide
| both of those numbers by some orders of magnitude.)
| kube-system wrote:
| Yeah, walk up to someone in the hood and tell them that
| for 15% more they could have got [insert product] that
| last 2x as long. You're gonna get punched in the face,
| because _they already know that_. They 're not dumb. What
| you're missing is the time-value of owning something
| _now_ , which is greatly amplified when life is tough.
|
| People don't want to walk their clothes basket down to
| the laundromat for one more month while they save for the
| nicer washer that lasts a little bit longer. They want
| the cheap one _now_ , because they just got off some
| shitty shift at work, and they're sick and tired of
| lugging their laundry down the street. Having a quality
| washer [x] years from now is not a desired part of the
| equation. Immediacy is of higher value.
| Dylan16807 wrote:
| 1. Immediacy doesn't help once it breaks and you can't
| buy a new one for _years_.
|
| 2. If everything lasts twice as long for 15% more, you
| can get a half-expired used one for even cheaper.
|
| > they already know that. They're not dumb.
|
| I think they're not dumb and they already know it's
| extremely difficult to figure out which brand fits that
| criteria, if any, so it's not worth it _because it 's
| such a gamble_.
| kube-system wrote:
| > it's not worth it because it's such a gamble.
|
| That's also true. At the individual unit level, small
| differences in MTTF/MTBF are negligible because product
| failures are naturally distributed anyway. The mean time
| is just a mean, and nobody gives a shit about a good mean
| product failure rate when theirs happened to fail below
| the mean. That's true no matter how much you spent.
| mike50 wrote:
| Engineers are to consider public safety first. This is
| not negotiable for real hardware engineering. Poor people
| could always purchase used appliances.
| kube-system wrote:
| I agree that products shouldn't be unsafe. And value
| engineering does not mean making products unsafe.
|
| > Poor people could always purchase used appliances.
|
| The reality in mid 20th century US demonstrates this
| isn't the case. Most went without the modern appliances
| that are commonplace today.
| Dylan16807 wrote:
| > If consumers really wanted to pay a premium for high
| duty-cycle equipment with premium lifespans, they can
| already do that by buying commercial grade equipment. But
| they don't.
|
| That costs a ton. I just want a better lifespan, I don't
| want to 20x the duty cycle and also pay B2B prices.
|
| It's too hard to figure out which consumer products have
| a better lifespan, so companies do a bad job of catering
| to that need. This makes companies try too hard to be
| cheapest, and they often fall below the sweet spot of
| longevity versus price. Then everyone is worse off.
| That's not the fault of the engineer but it still means
| the engineer is participating in making things worse.
| kube-system wrote:
| > That costs a ton. I just want a better lifespan, I
| don't want to 20x the duty cycle and also pay B2B prices.
|
| Therein lies the problem. A more durable product exists,
| and yet, even _you_ don 't want to pay more for it. And
| you are likely much more privileged than the rest of the
| world. What do you expect the rest of the world to be
| doing? Most of the world isn't picky about whether their
| hand mixer has plastic bushings or ball bearings. They're
| are choosing between any appliance at all and mixing
| their food with a spoon.
|
| > It's too hard to figure out which consumer products
| have a better lifespan, so companies do a bad job of
| catering to that need.
|
| There are many companies that try to break this barrier
| over and over, with tons of marketing material
| proclaiming their superiority. Why do they all fail?
| Because their hypothesis is wrong. The majority of the
| mass market _doesn 't want_ appliances that last for tens
| of thousands of hours. Most people use their appliances
| very lightly and for short periods of time before
| replacing them.
|
| I think a lot of people on this forum have points of view
| tainted by privilege. Poor people aren't dumb, they know
| that they are buying cheap stuff that doesn't last as
| long as more premium options. They're making these
| options _intentionally_ because a bird in the hand is
| worth more than two in the bush to them.
| Dylan16807 wrote:
| > A more durable product exists, and yet, even you don't
| want to pay more for it.
|
| This is disingenuous as hell.
|
| I want to buy a version that cost 15% more to make. I
| don't want to buy a version that cost 3x as much to make
| (or is priced as if it does).
|
| When I can't find the former, that is part of problem.
| When I don't buy the latter, that is _not_ part of the
| problem.
|
| > They're making these options intentionally because a
| bird in the hand is worth more than two in the bush to
| them.
|
| The best way to have the most birds in hands on an
| ongoing basis is to optimize for both price _and_
| lifetime per dollar, not just price.
| robertlagrant wrote:
| > I realize ethics are no longer understood by much of
| Western society because the culture teaches
| transactionality, worships trickle-down economics and
| greed, and hyperindividualism.
|
| You realise incorrectly, I would say. It's very
| defensible to claim that Western society has the most -
| by a giant margin - social, economic and technological
| advances in history, and to boil it down to this is just
| a bit silly, in my opinion.
| Dylan16807 wrote:
| > And? That just sounds like they have good engineers. If
| you are designing a machine, you have an target lifetime.
| You'd obviously want the product to last through the
| warranty period, because warranty claims are a cost to
| the company.
|
| > Every choice of a component affects lifetime. Designers
| of mass-market products can't just use premium components
| everywhere -- the mass market will not pay steep premiums
| for otherwise equivalent products.
|
| Dying just out of warranty is only okay if the warranty
| covers the actual expected lifetime of the product. And
| for appliances, it doesn't.
|
| The difference between a 5 year washing machine and a 30
| year washing machine is not very big. Anyone pinching
| those specific pennies is doing a bad thing.
| kube-system wrote:
| If you think people want 30 year old washing machines,
| you're kidding yourself. Do you remember what washing
| machines were like in the 1990s? They were noisy and tore
| up clothing. Not only would I not want to use one of
| these outdated machines, nor display it in my home, but I
| also wouldn't have wanted to _move it_ to the dozen
| different addresses I have lived at since then.
|
| At least in the US, people move frequently, and a washing
| machine that lasts for decades isn't even a benefit,
| because they'll likely have left it behind.
|
| > The difference between a 5 year washing machine and a
| 30 year washing machine is not very big. Anyone pinching
| those specific pennies is doing a bad thing.
|
| Absolutely right, it's only a matter of tens of dollars,
| probably. However, retail consumer appliances live and
| die at the margins. Nobody is opening up their washer to
| inspect the components to see if the $510 washer has
| better components than the $499 washer. All else equal,
| they're buying the $499 washer 90% of the time. Your
| fixed costs are going to eat you alive when spread across
| your fewer units, and retailers will stop carrying your
| product because it isn't moving.... All the while the
| $499 washer is going to be sitting in that home 5 years
| from now when the realtor puts a sign out front. And
| literally zero people are buying a house based on the
| bearings in the washing machine.
| Dylan16807 wrote:
| > If you think people want 30 year old washing machines,
| you're kidding yourself.
|
| You say this in the same breath you talk about people
| being desperate for any cheapest appliance instead of
| having nothing?
|
| > And literally zero people are buying a house based on
| the bearings in the washing machine.
|
| Well that's them being dumb.
| consp wrote:
| > And? That just sounds like they have good engineers. If
| you are designing a machine, you have an target lifetime.
| You'd obviously want the product to last through the
| warranty period, because warranty claims are a cost to
| the company.
|
| Product have an expected lifespan longer than the
| warranty period. This is malicious if given as a target.
| I'd like to see MTBF numbers on everything so people can
| lump together and sue the shit out of manufacturers who
| do this. Would also make it easier to check the 25$ light
| bulb.
| kube-system wrote:
| > Product have an expected lifespan longer than the
| warranty period. This is malicious if given as a target.
|
| Also it is mathematically stupid, because products do not
| fail at consistent rates, nor are they used by customers
| are equal rates. If you want to minimize warranty costs,
| you _do_ need to target some mean lifetime well beyond
| the warranty period.
|
| MTBF (or MTTF) might be useful number if you buy 100
| light bulbs, but is not really a useful number for you
| buying one appliance. Product failures don't follow a
| normal distribution. The stuff that ticks people off
| about shitty products is the infancy-failure part of the
| bathtub curve -- It's when you get 13 months out of a
| $200 blender that fails in infancy that you're pissed.
| Not when you get 24 months out of a $20 blender that
| fails from end-of-life.
| pwg wrote:
| > It's not my fault if other people are too dumb to
| comprehend TCO because I would buy the $25 bulb if it had
| a 30 year warranty.
|
| A 30 year warranty would certainly make a difference in
| the decision making. But more typically you see the $3
| bulb, with a 1yr "warranty", next to the $25 bulb, and
| the $25 bulb either has an identical 1yr warranty, or has
| a warranty period not commensurate to the price
| difference, such as a 2yr warranty.
| djmips wrote:
| There was a documented conspiracy in the past to limit
| the life of incandescent bulbs. Humans haven't changed
| that much.
|
| https://en.m.wikipedia.org/wiki/Phoebus_cartel
| owenversteeg wrote:
| I agree with what you said - engineers do the best they
| can with the budget but the budget is small because
| people won't pay for things that last - but it's worth
| saying that any boards with electrolytic capacitors have
| an inherent built in expiration. Any product with rubber
| has an expiration. Any product with permanent batteries,
| glued or sealed assemblies, or no spare parts. Much of
| that is with the customer's budget, sure. But these days,
| even among expensive things, nearly nothing is built to
| last.
| sillystuff wrote:
| Not LED light bulbs specifically, but...
|
| "The Phoebus cartel engineered a shorter-lived lightbulb
| and gave birth to planned obsolescence"
|
| https://spectrum.ieee.org/the-great-lightbulb-conspiracy
| RulerOf wrote:
| It's true that the Phoebus cartel arranged to have light
| bulbs die after a certain number of hours, but bulb
| lifetime is a trade off between lumens, filament life,
| and energy consumption. The cartel-defined lifetime limit
| sits very close to the sweet spot for all of those
| metrics for incandescent bulbs.
|
| Technology Connections explained this well in a video
| about a year ago: https://youtu.be/zb7Bs98KmnY
| dotancohen wrote:
| > bulb lifetime is a trade off between lumens, filament
| life, and energy consumption
|
| At a specific temperature, using specific materials.
|
| There is no reason to suspect that material science would
| not advance. Or other constraints would change. A
| specific company choosing that particular sweetspot for a
| particular product line is fine. But a collusion between
| companies dictating that specific constraint (in lieu of,
| e.g., wattage per lumen) is too clear a marker of anti-
| consumer intent.
| graemep wrote:
| The problem is that consumers cannot tell whether the
| more more expensive one is high quality or whether it is
| just the same as the cheap one, just priced higher.
|
| There have been plenty of discussions on HN about brands
| that used to produce durable products no longer doing so.
| I mostly buy cheap stuff because I assume that everything
| will be built as cheaply as possible, so I will get
| something that will not last anyway.
| andrewflnr wrote:
| Please think for a moment not only about whether it's
| feasible for AMZN to run a safety testing program for all
| possible consumer products of our modern technological
| civilization, but whether you really want them to be in
| charge of it. Maybe they should just require
| certifications of testing in the jurisdictions where
| those products are sold?
| gopher_space wrote:
| Isn't faking certs already a problem?
| andrewflnr wrote:
| Probably. Is it a worse problem than Amazon inspecting
| themselves would be? Is it a worse problem than Amazon
| demonstrably already has with policing counterfeits? I'm
| just saying, you could hardly ask for a less-qualified
| authority for product testing. At least with independent
| certs it's vaguely possible to align the incentives
| correctly. With Amazon the incentives would be hosed from
| the start.
| kube-system wrote:
| > Intentional planned consumption/obsolescence
|
| No it isn't. It is simply optimization of price and the
| features/form-factor that many buyers have demanded.
|
| If anything, the lifespan of a ~$1.50 household LED bulb
| is quite incredible. I'm not sure exactly how anyone
| _would_ be able to increase the lifespan at that price
| point and keep the traditional Edison form factor.
|
| > Amazon should be required to test all [..] products on
| its site such that they can prove safety and standards
| conformance.
|
| No, the manufacturers should be required to... the same
| way it works for literally every other product with
| safety regulations.
| com2kid wrote:
| > If anything, the lifespan of a ~$1.50 household LED
| bulb is quite incredible. I'm not sure exactly how anyone
| would be able to increase the lifespan at that price
| point and keep the traditional Edison form factor.
|
| I don't think I've had any last more than 5 years.
|
| If you bought a cutting edge LED bulb back in 2002 or so,
| those had a life expectancy of over 60 years, and the
| build quality was such that you could reasonably expect
| to get that.
|
| There are plenty of teardowns on YT showing how poorly
| even major brand name LED bulbs are put together.
| kube-system wrote:
| Yeah I would hope those bulbs were built pretty well,
| they were crazy expensive... expensive enough that they
| wouldn't be competitive in lifetime-per-dollar against
| today's crappiest bulbs even if they lasted a person's
| entire lifetime.
|
| > I don't think I've had any last more than 5 years.
|
| Do you shut them off every 3 hours? That's probably what
| the estimate on the box is based on. Run the same bulb
| half the day and you'll only get 2.5 years out of it.
|
| > There are plenty of teardowns on YT showing how poorly
| even major brand name LED bulbs are put together.
|
| I've seen them. And dissected my own. Still, at the price
| that modern LED bulbs are being made, I'm surprised
| they're built as well as they are. Brand name Sylvania
| bulbs are $0.79/ea in a bulk Amazon right now.
| com2kid wrote:
| > I've seen them. And dissected my own. Still, at the
| price that modern LED bulbs are being made, I'm surprised
| they're built as well as they are. Brand name Sylvania
| bulbs are $0.79/ea in a bulk Amazon right now.
|
| LED bulbs aren't lasting any longer than incandescent
| bulbs used to. My house has 2 bathrooms, one had
| incandescent bulbs when I moved in and I didn't bother to
| replace them. Those incandescent bulbs have outlived
| multiple sets of LED bulbs in the other bathroom.
|
| I honestly worry about the increase in e-waste with LED
| bulbs vs the old incandescent bulbs.
|
| > Do you shut them off every 3 hours? That's probably
| what the estimate on the box is based on. Run the same
| bulb half the day and you'll only get 2.5 years out of
| it.
|
| Which given that LEDs should damn well last 20-30 years
| of always being on, this is all a farce. I can't even pay
| 2x the price to buy a bulb with an honestly stated
| lifetime on it.
|
| > Yeah I would hope those bulbs were built pretty well,
| they were crazy expensive... expensive enough that they
| wouldn't be competitive in lifetime-per-dollar against
| today's crappiest bulbs even if they lasted a person's
| entire lifetime.
|
| I bet they would be. Given LED bulbs last less than 3
| years now, with some not even lasting 2 years, a 20-30
| year bulb could cost 4x as much and be competitive.
|
| The real problem is that those long lifetime LED bulbs
| are not driven as hard, so the light output isn't nearly
| as high. AFAIK all research in the last 20 years has been
| into bright LEDs with meh lifetimes, so I wonder if it is
| even possible to mass produce long lifetime consumer LEDs
| anymore.
|
| (Except the LEDs in all my consumer electronics have no
| problems staying on for 5 years non-stop! Tiny output,
| long lifespan...)
| rascul wrote:
| > LED bulbs aren't lasting any longer than incandescent
| bulbs used to
|
| They tend to last a lot longer for me.
| harimau777 wrote:
| The problem is that the manufacturers lie and say that
| the LED bulbs will last for many years when they don't.
| kube-system wrote:
| The claim they put on the box is typically true, but
| based on some damn modest usage. (e.g. 3 hours per day in
| ideal environmental conditions) And of course, a mean-
| time-to-failure figure to someone with one bulb built
| with minimal QA is just a dice-roll when faced with the
| bathtub curve of product failures.
| JJMcJ wrote:
| Recently read that if you are going to be using an LED
| bulb in an enclosed space, buy bulbs designed for the
| high temperature, otherwise you WILL get premature
| failures in bulbs that will last for years in ordinary
| lamps.
|
| https://duckduckgo.com/?t=lm&q=led+bulbs+enclosed+fixture
| +ra...
| bmicraft wrote:
| Alternatively, there are now much more efficient bulbs
| available. If they're passing A under the new EU Energy
| Label (from 2021) they'll barely be warm to the touch.
| outworlder wrote:
| > Any much older than that need to be checked out-of-
| circuit for ESR and then capacitance
|
| And that's a very time consuming and somewhat risky
| operation on an old machine you want to keep running.
| Some old PCBs are quite fragile.
|
| I wish there was a way to test capacitors without
| removing them.
| mgsouth wrote:
| You can test ESR in-circuit, with caveats. Here's a good
| thread from EEVblog [1].
|
| [1] https://www.eevblog.com/forum/beginners/is-there-any-
| way-to-...
| anon_cow1111 wrote:
| Here's a question for EE nerds that happen to be reading
| this (maybe in the future).
|
| What if I have a stash of big electrolytics that have
| been out of service for 10+ years? I know that I need to
| reform them over a few days, but can they even run at
| spec after so long out of operation?
|
| We're talking BIG stuff, 400v, 200+J each
| buescher wrote:
| For hobby or laboratory purposes, it's worth a try. Some
| probably will come back completely.
|
| But if you wanted to use them in production, and be able
| to blame me when it didn't work, I'd say no.
| 83 wrote:
| Bipolar electrolytic capacitors are a thing, I recently had
| to solder up a handful of them in some audio circuits.
| nuancebydefault wrote:
| Once you have experienced blowing up a reversed elcap you
| will never forget its orientation. I never understood though
| what makes it leak current and hence heat up.
| kevindamm wrote:
| There's an aluminum oxide layer as a coating on both the
| anode and cathode inside the (electrolytic) capacitor.
| Under forward voltage it will gradually thicken but under
| reverse voltage it dissolves and causes a short. This
| increases the temperature which causes hydrogen ions to
| separate and bubble through the material, increasing
| pressure within the capacitor package until it bursts.
| consp wrote:
| The thickening under forward voltage explains the
| "recovering cap" phenomenon with some old caps. Didn't
| know that.
| marcosdumay wrote:
| Modern electrolytic caps don't burn like they used to.
|
| The last few times I made a mistake, there wasn't even an
| explosion, even less a short-circuit. The thing slowly
| boiled and bubbled or unfolded.
|
| Anyway, it blows up because the capacitor's insulation
| layer isn't some stable material, it's a tiny oxide layer
| built over the metal plate by anodization. If you put a
| high voltage on it with the wrong polarity, you reverse
| that anodization and short the liquid and the metal
| electrodes.
| rasz wrote:
| Commodore struggled with same mistakes on negative rail in Audio
| section, but also somehow on highend expensive CPU board.
|
| https://wiki.console5.com/wiki/Amiga_CD32 C408 C811 "original may
| be installed backwards! Verify orientation against cap map"
|
| A4000 https://wordpress.hertell.nu/?p=1438 C443 C433 "notice that
| the 2 capacitors that originally on A4000 have the wrong
| polarity"
|
| Much worse is Commodore A3640 68040 CPU board aimed at top of the
| line A3000 and A4000
| http://amiga.serveftp.net/A3640_capacitor.html
| https://forum.amiga.org/index.php?topic=73570.0 C105 C106 C107
| silkscreen wrong, early revisions build according to bad
| silkscreen.
| fredoralive wrote:
| Typical Amiga fanboyism and Apple envy, if a Mac does something
| they have to prove the Amiga outdid it. "Only one model with a
| reverse polarity capacitor? With Commodore it was a systematic
| issue!"
| bogantech wrote:
| > Typical Amiga fanboyism and Apple envy, if a Mac does
| something they have to prove the Amiga outdid it.
|
| I think we're envious that Apple did a better job of
| engineering their systems
| hettygreen wrote:
| They were probably expecting these to fail a few months after the
| warranty expired.
| omoikane wrote:
| I wonder if there were any bootleg boards that copied the
| silkscreen mistake, but didn't use those 16V capacitors, and
| ended up catching fire.
| PeterStuer wrote:
| In the mid 80's I was the head of the CS student chapter. We ran
| the computer rooms for the science faculty. We had a room with
| about 20 Mac 128k. I do not know where Apple sourced their
| capacitors from, but these were not A-tier. A Mac going up in a
| puff of white smoke was a weekly occurrence. We had a few in
| reserve just to cycle them in while they were out to Apple for
| repair.
|
| P.S. still my favorite Mac of all time was the IIcx. That one
| coupled with the 'full page display' was a dream.
| fredoralive wrote:
| With things like the Mac 128k, reliability issues may partly be
| down to Steve Job's dislike of cooling fans.
| m463 wrote:
| To be honest, cooling fans never get the attention they
| deserve and end up whiney or buzzy.
|
| That said, apple did a really good job with mac pro cooling
| fans where the shroud spun with the blades.
|
| I think it did better than the the best PC cooling fans like
| noctua.
| Melatonic wrote:
| I always built PCs with the largest diameter fans possible
| - not sure why so many things come with tiny fans. Loads
| more airflow with less noise and even if they do spin up
| fast the noise they make is much more pleasant.
| MBCook wrote:
| I was just thinking of the Apple III the other day.
|
| If I remember, jobs had them not include a cooling fan. As it
| would heat up and cool down the chips in the motherboard
| would work their way out of the socket. So one of the
| official solutions to try if you were having issues would be
| to drop it a couple of inches to try and get the chips to re-
| seat inside.
|
| Crazy.
| yetihehe wrote:
| On the other side, we had intern at our (very small) company
| and he used his own mac. One time he had to debug a mains-
| powered device. He decided that he will try connecting it to
| both mains AND programming dongle without separating
| transformer. He fried the dongle (it literally exploded,
| plastic lid banging on desk in sudddenly silent office is the
| most memorable thing), the company provided monitor and device,
| but somehow his private mac mini survived all this while being
| in the middle.
| jdbdbcjd wrote:
| That sounds fishy, even if the debugged device directly
| interfaced mains, the Mac doesn't. And even if it did, how
| high would the probability be that both machines were on
| different circuits with phases so much out of sync that it
| would matter?
|
| Unless I misunderstood your story
| yetihehe wrote:
| That device was a cheap wifi power plug, had cheap
| unisolated power supply, it was never intended to have user
| accessible electrical parts sticking out, so no need for
| isolation. In such cases device has common ground with ac
| voltage. I don't know all specifics, but NEVER connect any
| single terminal of 220V plug to your computer ground (usb
| ground in this case). When it's properly grounded, most
| devices will survive this. But somehow monitor connected to
| that mac didn't survive it. And several milliseconds of
| full 220V before circuit breaker reacted, made very thin
| traces in debugger pretty much vaporise and explode.
| nuancebydefault wrote:
| If i remember correctly, a lot of power supplies of cheap
| electronics have AC-coupled the low voltage side with the
| mains side. There's no physical wire, just a capacitor.
| You can often feel the AC when touching the 'safe' side
| of the adaptor.
| amluto wrote:
| Forget "cheap". As far as I can tell, many modern
| ungrounded power supplies, including Apple's, have enough
| A/C coupling from the line to the output that you can
| feel a bit of tingling when you touch a metallic object
| connected to the output.
| spockz wrote:
| How is this even allowed? My tv had it. My MacBooks since
| time memorial have it. They all feel "spicy".
| ChrisClark wrote:
| My Fold 5 has that feeling along the hinge when charging
| too, no matter the charger I use. I guess it's considered
| safe, but it's weird.
| wbl wrote:
| The Y capacitor is needed to allow the EMI to have a way
| to ground from the output rather than going out and
| getting radiated by the output lines.
| amluto wrote:
| I don't believe for a second that this is actually
| necessary in a way results in that spicy feeling. I do
| believe that it's far cheaper to use a Y capacitor than
| to come up with a better filter network that works well,
| though.
| wbl wrote:
| Common mode noise filtering is either going to be purely
| inductive or need a Y-cap. No other way around it.
| amluto wrote:
| One can build lots of things out of inductors and
| capacitors. I bet it's possible and even fairly
| straightforward to built a little network to allow high
| frequencies to pass from output to the two line inputs
| with low impedance but that has extremely high impedance
| at 50 and 60 Hz (and maybe even at the first few
| harmonics). It would add components, cost and volume.
|
| I bet this could be done at the output side, too. And a
| company like Apple that values the customer experience
| could try to build a filter on their laptop DC _inputs_
| to reduce touch currents experienced by the user when
| connected to a leaky power supply. Of course, the modern
| design where the charging port is part of a metallic case
| might make this rather challenging...
|
| (Seriously, IMO all the recent MacBook Air case designs
| are obnoxious. They have the touch current issue and
| they're nasty feeling and sharp-edged.)
| wbl wrote:
| The capacitor has to see the common mode voltage. Where
| do you put the other end?
| amluto wrote:
| Off the top of my head? Make a little gadget that's an
| inductor and capacitor, in parallel, tuned to 60 Hz (i.e.
| a band-stop filter) and, in series with that, a Y
| capacitor. Wire up this gadget in place of the Y
| capacitor, so you end up with two of them (line to output
| negative and other line to output negative, perhaps). Or
| maybe you just have one, and you connect it between the
| normal pair of Y caps and the output. It will have very
| high impedance at 60Hz, enough impedance from DC to a few
| kHz to avoid conducting problematic amounts of current at
| DC or various harmonics, and low enough impedance at high
| frequencies to help with EMI. It might need a couple
| types of capacitor in parallel in the band-stop part to
| avoid having the high-frequency impedance of the
| presumably large-ish capacitor in parallel with the
| inductor being a problem, and it might be an interesting
| project to tune it well enough to really remove the
| annoying touch current, especially if you believe in 50Hz
| and 60Hz operation. Maybe a higher order design would
| work better, but the size would start to get silly.
| mgsouth wrote:
| Totally believable if the debugging device was doing
| something with a serial port. I once hacked something
| together to interface a PC serial port to a Raspberry Pi.
| The PC serial is real-ish RS-232, with negative voltages.
| The Pi side was just 0/3.3V positive. I had a nice 18-volt
| power brick laying around, and just split it's output down
| the middle--what was 0 volt ground was used as -9 volts,
| the middle voltage was now 0 volt ground, and the 18-v line
| was now +9 V.
|
| At first everything seemed OK. but when I plugged a monitor
| into the PI I Was Made To Realize a) the nice 18-volt PS
| really was high quality, and although it was transformer-
| isolated its output ground was tied to the wall socket
| earth, b) monitors also tie HDMI cable ground to earth, and
| so c) my lash-up now had dueling grounds that were 9V
| apart.
| sneak wrote:
| IIcx was my first computer! I still have mine.
| Animats wrote:
| Does the -5V rail do anything other than power old RS-232 ports?
| zargon wrote:
| Macs have RS-422 ports, not RS-232. But, no.
| ethernot wrote:
| There are so many cases of this sort of stuff it's unreal. But it
| gets even stupider.
|
| I found one a few years back when I repaired a linear power
| supply. This required me to reverse engineer it first because
| there was no service manual. I buzzed the whole thing out and
| found out that one of the electrolytic capacitors had both legs
| connected to ground. They must have shipped thousands of power
| supplies with that error in it and no one even noticed.
| iknowstuff wrote:
| Name and shame!
| ethernot wrote:
| Voltcraft. Can't remember the model number.
| chrisdhoover wrote:
| Way back when a co worker was powering up a fire alarm control
| panel. Poof, capacitor popped and damaged his eye
| jcims wrote:
| I have a 3D printer where presumably a smoothing cap just fell
| off the X axis controller section of the mainboard. Didn't make
| a lick of difference in anything operationally. Still works
| great.
| robomartin wrote:
| It could be there to control emissions. You'd need to analyze
| the circuit to determine its purpose.
| jcims wrote:
| Very possible! I actually have a 100MHz scope and sdrs that
| tune from 9khz to 2ghz, could be an interesting distraction
| on the weekend to see if that axis is any noisier than the
| others.
| klysm wrote:
| Checks out, most boards are made with very conservative
| amounts of decoupling capacitance because it's way easier
| than dealing with random failures due to not enough
| capacitance
| jopsen wrote:
| I've understood that capacitors can be used for timing, or
| smoothing a voltage after a power regulator (I think).
|
| How/what does adding capacitance help with?
| pokeymcsnatch wrote:
| Voltage spikes from line inductance, voltage drop-outs
| from line resistance. Basically you have little
| reservoirs of charge scattered all around the board
| (current flow isn't instantaneous in a real circuit).
|
| It helps to always think of current draw in a compete
| loop, out the "top" of the capacitor, through your IC,
| and back into the ground side (this isn't necessarily
| what's happening physically). Shorter loop means less
| inductance, shorter traces less resistance.
| klysm wrote:
| Smoothing is part of the story: but the important
| question is what is causing the roughness? Switch mode
| power supplies have inherent output ripple that can be
| filtered, but that's distinct from transient variations
| in the load. Decoupling capacitors are used to provide a
| low impedance path at high frequencies i.e. fighting
| inductance.
| klysm wrote:
| That seems like one the least harmful mistakes you could make.
| Capacitors are sprinkled all over boards in excess's because
| it's probably better than not enough capacitance.
| talideon wrote:
| It would probably be an idea to point out here that those are
| decoupling capacitors used to reduce noise. Capacitance isn't
| the point with them, but that they pass AC while blocking DC.
| Not that the capacitance hurts, mind.
| klysm wrote:
| But that's what a capacitor does? The point is to provide a
| low-inductance path, not really block DC
| andrew-jack wrote:
| Apple should be mandated to issue a recall for these
| motherboards.
| likeabatterycar wrote:
| The author seems to misunderstand PCB design flow. This is
| neither a "factory component placement issue" nor a silkscreen
| error. The error is in the schematic.
|
| The layout CAD is often done by a different team that follows the
| schematic provided by design engineering. Automated workflows are
| common. The silk screen is predefined in a QA'd library. It is
| not their job to double check engineering's schematic.
|
| The components are placed per the layout data.
|
| Both those teams did their jobs correctly, to incorrect
| specifications. In fact, the factory performing assembly often is
| denied access to the schematic as it is sensitive IP.
|
| If you're going to cast blame on a 30 year old computer, at least
| direct it at the correct group. It wasn't soldered incorrectly at
| the factory. They soldered it exactly how they were told to -
| backwards.
| rcxdude wrote:
| >The layout CAD is often done by a different team that follows
| the schematic provided by design engineering.
|
| Just as a note, this is a fairly archaic way of working
| nowadays. At my place schematic design and layout go hand-in-
| hand, and we rejected a candidate because he didn't do the
| latter. The main reason is layout is no longer an afterthought,
| it's a key part of the electrical design of the system, and
| there's little room for a tedious back and forth between the
| circuit designer and the person doing the layout about what
| traces are and aren't important to optimize for various
| attributes.
| jimnotgym wrote:
| And yet it is not at all unusual for a production engineer to
| spot these faults and pass them back to the design engineers
| for rework.
| rcxdude wrote:
| Also true! Most common when you accidentally screw up a
| footprint and it doesn't fit the part on the BOM. A
| backwards part is the kind of thing they're not likely to
| pick up on (if it's marked on the silkscreen incorrectly,
| at least), but some do.
| analog31 wrote:
| Indeed, and this is true in other engineering activities such
| as mechanical design as well. Possibly with the exception of
| very large shops, there are no draftsmen any more, and the
| design engineer also creates the production drawings. And the
| software lends itself to this. Schematic / layout, and design
| / drawing, are joined together in the design software. It
| would be very hard to make a mistake like the one in TFA
| today.
|
| Even the free software that I use -- KiCad -- would ding me.
|
| We make bigger mistakes instead. ;-)
| lmpdev wrote:
| I have my childhood LC II in storage
|
| I wonder if it has the same defect
| fishgoesblub wrote:
| If anything you should open it up to check for any leaking
| batteries/capacitors.
| magic_smoke_ee wrote:
| From around 2011-2015, I sometimes talked to an ex-Navy
| electrical tech who said he was also an early Apple rework tech
| in the SF Bay Area. He had no shortage of work fixing
| manufacturing problems, adding rework improvements, and building
| custom test equipment until they laid him off, outsourced his job
| to some random country, and then he was homeless until around
| 2016.
| nsmog767 wrote:
| not the Flux Capacitor?!?!
| johnklos wrote:
| It's a good thing that these machines don't even need -5 volts.
| With just the positive voltages provided, RS-422 still works,
| including LocalTalk.
|
| I think the -5 volts is only there in case an expansion card
| needs it.
| upofadown wrote:
| I did a bit of research on this because I was confused about
| why RS-422 needed -5V. Normally the driver is powered off +5
| and 0 Volts for RS-422. By increasing the swing down to -5, the
| Mac port is compatible with RS-232. So a Mac of this era can
| connect to a modem with a specially wired cable. No level
| conversion is required and RS-422 receivers are required to
| work down to -6V so the Mac is producing completely valid
| RS-422 at the same time.
|
| Most RS-232 receivers of that era had a fair amount of gain
| with a transition point close to 0V. So only a little minus
| voltage would be required in practice, not the entire -5V. So
| just as long as the reversed capacitor was not entirely
| shorting out the rail things would have worked.
| Waterluvian wrote:
| I spent my mid childhood on an LCIII. One summer my friend
| brought his Performa over and we tried to play 1v1 Warcraft 2
| over the serial port. LocalTalk or something alike?
|
| But it just never quite worked right. I remember how frustrated
| and confused my older brother was. The computers would sometimes
| see each other but would drop off so easily.
|
| Was this that?!
| sgerenser wrote:
| Iirc Warcraft 2 came out well after the LCIII was obsolete (in
| fact, I'd be surprised if it was ever released for 68k Macs).
| Official system requirements list PowerPC and MacOS 7.6 as
| minimum required[1]. Maybe thinking of a different game?
|
| [1]
| https://www.blizzplanet.com/blog/comments/warcraft_ii_tides_...
| Waterluvian wrote:
| We tried both WC1 and 2. Played both to death.
|
| WC2 worked mostly well but just kind of slower game speed.
|
| In fact I got Diablo running on the LC3. A level took like 10
| mins to load and it ran at 1fps though. :)
| etrautmann wrote:
| The first board I ever designed and had manufactured had a
| reversed tantalum capacitor on the power rails and exploded
| somewhat dramatically when powered up. Lesson learned!
| robomartin wrote:
| Brings back memories...
|
| About 30 years ago I designed my first PCB with frequencies in
| the GHz range. It was full of challenging transmission line paths
| with frequencies in the hundreds of MHz and above.
|
| I am still proud of the fact that all of the high speed signals
| worked as designed, with excellent signal and power integrity
| (the large FPGA was challenging). Emissions passed as well.
|
| I did, however, screw up one thing: DC
|
| I somehow managed to layout the DC input connector backwards!
|
| These boards were very expensive ($2K), so an immediate respin
| was not possible.
|
| I had to design a set of contacts to be able to flip the
| connector upside-down and make the electrons go in the right way.
|
| The joke from that point forward was that I was great at multi-
| GHz designs but should not be trusted with DC circuits.
| mhardcastle wrote:
| Why include that capacitor at all if it doesn't matter whether it
| works?
| rwmj wrote:
| If you look at the traces you can see the capacitor is right
| next to the power connector, on the -5V rail (which is not used
| for much, only for the RS422 serial port). The capacitor will
| be there to smooth the power supply when the machine is just
| switched on, or there's a sudden load which causes the voltage
| to "dip" above -5V. Basically it's like a tiny rechargable
| battery which sits fully charged most of the time, but can
| supplement the power on demand.
|
| So you can see why it probably didn't matter that this
| capacitor didn't work: It's only needed for rare occasions.
| RS-422 is a differential form of RS-232
| (https://en.wikipedia.org/wiki/RS-422) so being differential
| it's fairly robust against changes in load if they affect both
| wires. And the worst that can happen is you lose a few
| characters from your external modem.
|
| In addition, electrolytics can probably work when reversed like
| this, at least a little bit. It's not exactly optimal and they
| might catch fire(!).
| phire wrote:
| _> It 's only needed for rare occasions._
|
| The two RS-422 ports are actually used quite often on these
| old Macs for printers, modems and apple talk networking. It
| was the only communication port, as there was no parallel
| port. They were backwards compatible with RS-232.
|
| So it obviously worked well enough.
|
| The backwards cap was measured to reduce the voltage to about
| -2.4v.
|
| I suspect that all it did was reduce the maximum range, which
| started at a massive 1,200 meters for RS-422 (and a good 10m
| for RS-232)
| _whiteCaps_ wrote:
| Also known as the Madman Muntz theory of Engineering :-)
|
| https://en.wikipedia.org/wiki/Muntzing
| qingcharles wrote:
| I never knew there was a name for this :)
|
| When I was a demo coder my artist friend would just
| haphazardly go through all my assembler code and snip random
| lines out until it stopped working to improve performance.
| foft wrote:
| It is not just Apple that did this, for example here is an
| equivalent from Atari:
| https://www.exxosforum.co.uk/forum/viewtopic.php?f=17&t=1698
| 0xbadcafebee wrote:
| Anyone else a veteran of the Great Capacitor Plague? Seen more
| than one fire in the server room due to bad capacitors. "Burning-
| in" your server became literal.
| yborg wrote:
| I have a Quadra 700 of this vintage that hasn't been powered up
| in 25+ years. Kind of wanted to fire it up again to experience
| the glory of A/UX one more time, but sounds like I'd have to
| replace all the lytics :/
| mmmlinux wrote:
| Do it sooner than later, the cap juice loves to eat PCB traces.
| same with the clock batteries, get those things out of there.
| rvense wrote:
| I think the Quadra 700 (and one or two other models) has
| tantalums on the mainboard from the factory.
| chefandy wrote:
| What's the liquid in the old capacitors? PCBs? (as in
| polychlorinated biphenyls... that abbreviation collision always
| annoyed me.)
|
| I think I know exactly enough about electronics to ask more
| annoying questions than someone who doesn't know anything at all.
| syncsynchalt wrote:
| "Wet" capacitors contain any number of liquid electrolytes.
| Could be something tame like ethylene glycol, boric acid,
| sulfuric acid, or nastier stuff like organic solvents (DMF or
| DMA which are poisonous, or GBL which is less lethal).
|
| Nothing as bad as PCBs as far as I'm aware.
| chefandy wrote:
| Cool, thanks. I think I should learn how these components
| actually work. Individually they seem pretty simple.
| mike50 wrote:
| PCBs were only used in oil capacitors and some transformers.
| Generally these were used in motor and grid power applications.
| The only consumer applications are some motor capacitors and
| florescent light ballasts.
| chefandy wrote:
| Yeah I pretty much grew up (unknowingly) playing in an
| illegal unmarked chemical waste dump so it takes a lot to get
| my attention, but I opened up an old fluorescent desk lamp
| from the 60s I had that fried itself to see if it was fixable
| -- and found a small piece of crumbly asbestos shielding
| about the size of a business card stuck to a big leaky
| ballast. Pretty solid toxic waste combo. City hazmat got a
| sweet vintage lamp that day, sadly.
| 65a wrote:
| Electrolytics are usually nothing too fancy, but it is
| proprietary. Water and electrolytes, hence the name. PCBs are
| in the big transformers and what used to be called bathtub caps
| which looked like this
| https://i.ebayimg.com/images/g/VjwAAOSwfGJjYtHx/s-l400.jpg
| (think 1950s electronics stuff)
| mikewarot wrote:
| I've found a ground lug in a Kilowatt Grounded Grid amplifier...
| that didn't ground the grid.
|
| I found a bad solder joint that looked ok, but was intermittent,
| and had been that way, in a Television built in 1948 and used for
| decades.
|
| Bad design and assembly goes back forever, as near as I can tell.
| alain94040 wrote:
| Sounds like the person who designed the board followed a very
| simple and wise rule: always connect the negative side to the
| ground. Can't go wrong with that...
|
| until you have to deal with negative voltage (-5V). Another out
| of bounds bug.
| PcChip wrote:
| Didn't this also happen on some Asus motherboards a couple years
| ago?
| Karliss wrote:
| That one was Asus ROG Maximus Z690 Hero ~2years ago.
| namibj wrote:
| Sorry to hijack the thread, I couldn't directly reply to
| https://news.ycombinator.com/item?id=42092845 .
|
| The reason to not (just) use optical flow is that it isn't
| absolute. If you pattern your surface correctly, you can
| ensure that every few by few pixel region on a QR code like
| bitmaps surface is unique, and thus can be decoded into an
| absolute position. Basically a 2D absolute optical encoder
| fast enough to be part of a motor control loop.
| 1oooqooq wrote:
| what apple era are those machines? is this before or after Jobs
| shafted the engineering department on the sale and Woz had to
| give them bonus to keep them on the factory?
| rvense wrote:
| This is a good five years after Jobs left...
| 1oooqooq wrote:
| thanks. apple have been several companies depending on the
| era. if you're not a fan it's hard to keep track.
| sroussey wrote:
| I have an original Mac that no longer turns on. I bet there is a
| capacitor to replace. This is giving me the energy to go look for
| it!
| MBCook wrote:
| There's a very good chance the battery has leaked and caused
| quite a mess. Well capacitors are a problem the battery is the
| biggest one.
| weinzierl wrote:
| _" The capacitor might not have been doing its job properly if it
| was installed backwards, but it didn't seem to really be hurting
| anything."_
|
| _This_ is the buried lede! I am of the opinion that half of the
| capacitors in any modern circuit are useless; the trouble is we
| don 't know which half.
| moring wrote:
| Why is the pool of goo under C21 when it is C22 that is flipped?
| Bric3d wrote:
| It leaked when they removed them, it's a common issue with
| these capacitors and part of why people replace them.
| 1970-01-01 wrote:
| The best way to remove any aluminum SMD cap is to grab it with
| needle nose pliers, press it down into the PCB, and begin
| twisting them a under moderate pressure while alternating
| direction until they break away from the PCB. Never pull up!
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