Schematics  - Page 1
Forum section: electronics / general

author: blauerscharik
author_rank: Regular Contributor
timestamp: July 23, 2023, 07:44:22 pm
content: So I'm not old enough to know the time when electronics were sold with a manual and actual schematics of that device.(although I like to buy old stuff from flea markets which often have the manuals and schematics)Why did that mentality change?Were companies back then actually hoping the devices would be fixed instead of thrown away?Were the devices made to be repaired, i. e. the design of the device itself and the board layouts and stuff.Now companies are doing the exact opposite, but why? 5,000 different screws... everything is glued so it breaks when you try opening it... zero information of how things wok... etc. etc. etc.I guess the incentive is when it breaks you buy a new one, but why was it different before?Or wasn't it?

author: ataradov
author_rank: Super Contributor
timestamp: July 23, 2023, 08:07:43 pm
content: This changed when ASICs appeared. What is the point of having a schematic if it uses a part that you can't buy. My dad used to repair TVs. And over the years it became harder and harder. Once the TV got optimized to one IC, the schematics were still available, but they were pointless because apart from obvious cracks in the connector solder joints, that IC was the major culprit. For some time salvaged ICs were available, but then even that went away.And then with more MCUs and other programmable devices being used, just having the schematic is not enough, you need the firmware.There is mostly no point in having schematics for modern devices.And for the glue - people demand slicker and cheaper devices. Unless forced by the law, manufactures will optimize the price over anything else.

author: blauerscharik
author_rank: Regular Contributor
timestamp: July 23, 2023, 08:18:59 pm
content: Quote from: ataradov on July 23, 2023, 08:07:43 pmYes I see your point.But still, someone who designs a board still needs something to go by.I do understand that everything is getting more complicated and on a smaller footprint. Everything used to be through-hole boards now it's SMD and you're lost witout a microscope.What will the future be like?

author: ataradov
author_rank: Super Contributor
timestamp: July 23, 2023, 08:24:58 pm
content: Quote from: blauerscharik on July 23, 2023, 08:18:59 pmWhat do you mean? People that design the boards have the schematics for the boards they design.Quote from: blauerscharik on July 23, 2023, 08:18:59 pmIt is not economical to repair most of the consumer stuff anyway if you factor in the time. And most people will not be repairing their stuff on their own.So, things will be optimized to serve their useful life and be discarded. Increasing the price for everyone and making the design more complicated because a couple people may decide to repair it, may not balance well. Let's say you are making a power supply and instead of sonic welding the case, you decide to use screws. How many people will realistically be repairing the power supply instead of replacing it? But everyone will eventually discard it. So you will be discarding a lot of metal in the screws.

author: SiliconWizard
author_rank: Super Contributor
timestamp: July 23, 2023, 08:36:45 pm
content: That's a problem.Even if you arrange to make the hardware easier to repair (which will inevitably add significant cost, plus you always have the problem of availability for all the components that are used, modern components are - often - much shorter-lived than the old parts which had a lot of equivalents), there's now the software which has become a major issue.More and more devices rely on software to operate, and such software ends up becoming "obsolete" when the vendor decides to stop supporting the device. (It's often something around 2 to 3 years max for most consumer stuff apart from cars). So even if you could hypothetically repair a device forever, you'd be stuck with the latest version of software that was made available. And since more and more devices now need to interoperate with existing infrastructures, such software definitely does become obsolete in the sense that an older version may not support newer infrastructure and thus may make the device useless even if the hardware is still perfectly fine.That is true for mobile phones, but also increasingly for TV sets, and soon even your washing machine will need to have up-to-date software in order to work at all, as an internet connection might end up becoming a strict requirement for normal operation.In other words, the hardware side of things has certainly evolved a lot, making devices harder to impossible to repair, but the sofware side of things is every bit as problematic, and probably a lot more.Of course that could be eased up (at least as much as possible) by mandating that any company selling products with software must open-source the software of said products when it stops supporting it.That is pretty unlikely to happen, though. But who knows.

author: blauerscharik
author_rank: Regular Contributor
timestamp: July 23, 2023, 08:37:58 pm
content: Quote from: ataradov on July 23, 2023, 08:24:58 pmThat's what I mean, they could make it public, but like you said it might not be of much use.QuoteI guess that's the way it is sadly going.

author: blauerscharik
author_rank: Regular Contributor
timestamp: July 23, 2023, 08:48:31 pm
content: Quote from: SiliconWizard on July 23, 2023, 08:36:45 pmThat is also very true. And that I also don't understand.If a company stops producing a certain product why not make it open-source? But then I guess you might not buy their new line of product.It's the mentality of "If I can't have it or use it, then you can't have it or use it" You know who thinks like that.. children.But then all the companies advertise how 'green" they are

author: ataradov
author_rank: Super Contributor
timestamp: July 23, 2023, 09:17:30 pm
content: Quote from: blauerscharik on July 23, 2023, 08:48:31 pmCompanies license a lot of stuff from third parties. It is very hard to make the whole thing open. an opening just the stuff you own will not create a working firmware.Quote from: blauerscharik on July 23, 2023, 08:48:31 pmIt is not. I've been involved on one major effort to open source previously closed source code. It took us months. Apart from clearing all the license stuff, we had to make sure that the code builds outside of our corporate build environment. It was not easy. In our case open sourcing was the goal, so months of effort were justified. But if company gets nothing in return, it is hard to justify.

author: BrokenYugo
author_rank: Super Contributor
timestamp: July 23, 2023, 11:50:42 pm
content: Consumer electronics used to cost enough it made financial sense to pay skilled labor to do component level repair. E.G. TVs cost so much people would have a worn out CRT replaced with a rebuilt one, now when a TV quits working most people put it on the curb and go to the grocery store to pick up a new one.

author: VK3DRB
author_rank: Super Contributor
timestamp: July 24, 2023, 01:09:30 am
content: Quote from: ataradov on July 23, 2023, 08:07:43 pmNo, more like when surface mount devices appeared. The average Joe couldn't repair them and SMD parts were not available from hobbyist electronics stores. Even today most people can't even change an 0402 resistor, let alone a QFIC.

author: vad
author_rank: Frequent Contributor
timestamp: July 24, 2023, 03:49:03 am
content: The good old days when both the schematic and the operating system’s source code of Apple computer were published in the user manual are long gone.

author: ejeffrey
author_rank: Super Contributor
timestamp: July 24, 2023, 05:47:12 am
content: Quote from: VK3DRB on July 24, 2023, 01:09:30 amSurface mount components have never been a serious obstacle to professional or dedicated hobbyist repair. So you couldn't buy resistors from radio shack, you could get them from catalog distributors. Even high density BGAs are repairable if you can get the part.It's the parts you can't get because they are custom, or not for sale without an NDA, or obsolete, or requires unobtainable firmware.

author: mengfei
author_rank: Regular Contributor
timestamp: July 24, 2023, 06:47:40 am
content: Schematics became scares when the Middle Kingdom came to Power

author: tooki
author_rank: Super Contributor
timestamp: July 24, 2023, 09:18:08 am
content: Another factor might be the time and effort to create documentation. The loss of service manuals has occurred simultaneous to the loss of good user manuals.Back in 2009, I was hired by a small software company to do the English translation of their product. That involved several thousand text strings in the program (i.e. any text the program itself displayed, like the names of menu items, checkboxes, and other widgets, as well as error messages and the like), over a thousand context-sensitive help files. Then there was the 300-page manual, hundreds of FAQs, etc.Writing a manual like that is a ton of work, even just in one language. Really good manuals actually fill two roles: how-to guides for less-experienced users, and reference guides for experienced ones. That’s a big challenge in itself. Companies have been less and less willing to do that, instead putting out short “quick start guides” and then writing shitty FAQs to add information that should have been in the manual to begin with, and leaving the rest up to community self-help by offering user forums. I think it’s shameful.All of that is just for user documentation, which is something that a good technical writer can write mostly on their own. Public service documentation requires much more direct involvement of the engineering staff who actually designed the product. This makes that documentation even more expensive. And to boot, it often requires review by the legal department to ensure that no trade secrets are being divulged.In the end, most service documentation nowadays is produced for internal use only, often written by the engineers themselves. This avoids the need to have it reviewed by legal and rewritten/edited by the technical communication department.

author: mendip_discovery
author_rank: Super Contributor
timestamp: July 24, 2023, 09:35:27 am
content: It all changed because of money, mostly the desire to spend less and make more.Obsolete parts/machines so they can sell you new ones.Good manuals with descriptions cost money to make.If you want support then you can pay for it. Otherwise, use the community to help you.

author: Zero999
author_rank: Super Contributor
timestamp: July 24, 2023, 10:08:21 am
content: Quote from: ataradov on July 23, 2023, 09:17:30 pmBeing open source doesn't stop them making hardware repairable. Firmware can be provided in binary/hex format to prevent the user from seeing the source code.Quote from: vad on July 24, 2023, 03:49:03 amThat doesn't necessarily make it open source. The code could easily be licenced to the customer on the bases they don't copy it, or give it to anyone else.The other points made regarding, cost, usefulness and docmentation are valid, but open vs closed souce is irrelevant.

author: vad
author_rank: Frequent Contributor
timestamp: July 24, 2023, 06:24:03 pm
content: Quote from: Zero999 on July 24, 2023, 10:08:21 amIt definitely does not. The Apple 1 manual contains a legal copyright notice.My point is that 47 years ago, it was practical to print the source code of the entire operating system in a paperback book.

author: blauerscharik
author_rank: Regular Contributor
timestamp: July 24, 2023, 07:29:19 pm
content: Quote from: mendip_discovery on July 24, 2023, 09:35:27 amThat's what I think too.It's a shame that everybody just plays along with this nonsense, being it engineers or consumer who just want cheap stuff

author: hans
author_rank: Super Contributor
timestamp: July 24, 2023, 07:33:18 pm
content: I still think there issomepoint in having schematics of e.g. laptops or TV sets available.If you watch Lious Rossman Macbook repair videos, I'd risk a guess 2/3s+ of the fixes being a problem with power supplies or connectors. Some just went bad, others had liquid damage but could still be fixed.There are also other YT repair channels that show a similar story. SSD stop worked => PSU went bad. Fixed PSU, got data off the SSD, was a much cheaper fix than a clinical extraction of FLASH chips and then piecing together the data array (if at all possible if a controller secures the data in a board-unique way).Even simpler fixes like batteries going bad over time would easily extend the lifetime of a device. But no, they need to glued in, which saves them maybe a couple tens of cents, but it makes the device unnecessarily dangerous to work on once you need to slide poky things under the battery to undo the glue.But I honestly think these manuals are not available, because manufacturers will pull the copyright-card while instead they want customers to just buy a new device. A manufacturer has zero stake in making a battery user replaceable. The manufacturers can make zero profit on after-market battery sales, as clones will arrive In a few weeks that are compatible. It costs them money to add extra screws in production, and then you have the self-imposed "phones need to be thinner" and "phones need IP67 100m dive rating" which plays perfectly into the hands of offering less functionality for higher sale price.

author: blauerscharik
author_rank: Regular Contributor
timestamp: July 24, 2023, 07:36:08 pm
content: Quote from: tooki on July 24, 2023, 09:18:08 amLike another user said. Companies try to make more money with spending less, a real shame.

author: SiliconWizard
author_rank: Super Contributor
timestamp: July 24, 2023, 08:38:55 pm
content: Quote from: mengfei on July 24, 2023, 06:47:40 amWe can indeed link the trend to the outsourcing of our production to low-income, eastern countries, which allowed dirt-cheap production costs and thus promoted cheap, replaceable products rather than repairable, long-lived ones.

author: mengfei
author_rank: Regular Contributor
timestamp: July 25, 2023, 12:59:22 am
content: I worked in a china factory for a very long time, how long? that time they didn't have any kind of Cellphone brands but when they got hold of some of the tech & SCH of popular brands at that time, Nokia, SE, Siemens, LG, Boom! went the Electronic markets here. From Tamagochi to the now widespread use of A.I. coz the got their hands on those SCH & they really love to do some reverse engineering since they had a lot of time in their hands.