Schematics and knowledge sharing thoughts

[RoadrunnerOZ]

Yeah a lot of the board swap repairs back in the ‘80s and ‘90s relied on sending the faulty board back as exchange (warranty) or paying the price for a new replacement (non warranty) - some had reduced cost to supply with an exchange board, as the boards could be repaired. For some console repairs I had repair test jigs supplied by the manufacturer which had a power supply, edge connectors and test insertion points on a breakout panel. This started many years ago.

 

[vintageampfixer]

Yeah a lot of the board swap repairs back in the ‘80s and ‘90s relied on sending the faulty board back as exchange (warranty) or paying the price for a new replacement (non warranty) - some had reduced cost to supply with an exchange board, as the boards could be repaired. For some console repairs I had repair test jigs supplied by the manufacturer which had a power supply, edge connectors and test insertion points on a breakout panel. This started many years ago.

it's much the same process now ...

 

[RoadrunnerOZ]

Except for a few brands which I won’t name that require the whole machine to be returned to the supplier, they have representation in only one city in the whole country and no outlying service available - cost to send and return the product is on the end user which is pretty expensive for a warranty service and leads to long delays in getting the gear back and on the road. This is a big country (Perth to Melbourne for example is 3400Km, to Sydney 3900Km) with a relatively small population and I guess doesn’t get the same service support you’d get in Europe or the States. I used to manage a pro-audio store for about 10 years and we had to have loan/hire gear that musos could use while waiting for their gear to be repaired if it had to go to another city for warranty repairs. Some importers only have a container come in every 6 to 8 weeks or when it’s full if they don’t have the spares in stock and won’t do air import unless you pay for it.

 

[JohnRoberts]

I have been up to my neck in this game for most of my career and never designed a SKU to fail on purpose. I will concede that I have been out of the large company trenches for decades, but only shut down my last business about 4 years ago. FWIW that last SKU I designed had a three year warranty, and in the 3 years after I stopped selling them I got exactly zero warranty claims. I guess I screwed up and made the design too robust.

From a distance I can see aspects of modern manufacturing that make easy servicing difficult. It's hard for a vendor to support repair parts or sub assemblies when the production is done on the other side of the world in one huge batch and the next generation SKU may use newer completely different technology.

The only constant in the world is that it's always changing.

JR

 

[TimG]

That’s kind of cool you had actual data on the failures (zero) of your design project.

When I worked in TV news libraries I always wanted to know how many lawsuit claims my group had gotten, versus the “other group” for using 3rd Part Material, but the attorneys with the data weren’t always willing to share, making it more difficult to improve, iteratively.

 

[jp8]

Companies don't want the product you bought from them to be repaired
Companies want you to ditch the failed product and buy from them a new one, or the new model, or version MKII
Companies don't do and don't want to do any longer products that are made to last a lifetime

I don't think you can make this a generic statement. What do you base this on? This certainly doesn't apply to the product group of my company that I help develop. We're always proud to receive letters from happy customers (really, we do get them!) about the lifetime of the products we develop, manufacture and sell.

And if devices are sent in for warramty or repair, yes, we do often ditch the device. Especially the cheaper ones, because spending $50-$100 on fault finding and swapping out that $0.01 part makes no sense. We just swap out modules or complete devices.

Releasing the Schematics would make it easier for consumers to find they designed a product to fail, would make it easy to repair it and to share how to solve the weak points, and if all that happens they would not sell you a new unit

I don't think you can reliably predict lifetime from a schematic. And if you can to a certain extent, it's not always easy, or it's even impossible, to modify and improve the circuit on the given PCBA and in the given volume etc.

Planned Obsolescence is not a conspiracy theory it's very real and implemented in the majority of electronic products at the present.

Majority...? I take this as an opinion, rather than a fact. Unless you can point me to a source which has done some decent research on this.

Although there could be companies that design in Planned Obsolence ( which I translate to design for defined, short lifetime), it would mean that you would actually have to do extensive simulations and life testing to prove the planned short lifetime. After all, you don't want to sell products that fail too soon, as JohnRoberts already pointed out. Or that actually prove to be too good. Anyway, such extensive life testing is rather expensive and time consuming and I don't expect this is done a lot on cheap consumer goods. Or on expensive devices of which not many will be sold. I think short lifetime/high failure rate is more often a result from how products were developed, rather than being it planned for. Small R&D budgets, short development times without testing and iteration loops, ignorant developers making stupid design flaws, spending money on bells and whistles rather than quality etc. Just my opinion based on 40 years of hardware design experience, hardware repair and reverse engineering of many products Do not take as a fact...

Jan

 

[JohnRoberts]

That’s kind of cool you had actual data on the failures (zero) of your design project.

When I worked in TV news libraries I always wanted to know how many lawsuit claims my group had gotten, versus the “other group” for using 3rd Part Material, but the attorneys with the data weren’t always willing to share, making it more difficult to improve, iteratively.

Some people complain about my Peavey stories, but back last century while I was working there we decided to extend our warranty from 3 years to 5 years for competitive marketing reasons. We did a rigorous review of in-warranty and out of warranty repairs. Long story short, it was a no brainer and we extended the warranty 2 more years with no significant problems. Most failures are "infant" failures and occur relatively soon in a products life. Once they survive infant failure modes, they are usually good for several years if not abused.

During the investigation I found one modest analog power amplifier that had higher than expected field failures for that particular SKU's sales volume. It was not on our radar because it was a low volume seller and the service department knew how to fix the few that they saw, so they never complained. I asked the head of analog engineering to review that amp's field failures and he found a minor design flaw, one transistor had a marginal voltage rating. He wrote the engineering change order to use a higher voltage part and those field failures stopped. I'm sure if this was a higher volume SKU, the flaw would have been found sooner (squeaky wheel gets the oil).

JR

 

[brucega]

I bought a used Peavey mixer in the early '80s, 12 channel, transformer mic inputs, balanced outs, built into a road case. It was still working last year, but I gutted it. Was hoping to get the specs on the mic transformers.

I loved that mixer, even though it was a tank to lug out to jobs. Much respect!