Schematics and knowledge sharing thoughts

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Good points! I totally get companies wanting to QC their own repairs. Mostly concerned with the ones that have no service centers, and wont share schemos. I would sign an NDA, might be worth emailing a few companies about that. Haven't been offered that solution but I can inquire!
Totally agree most things are easy to get around in a block diagram sort of way. I don't have an issue repairing or figuring out circuits, just prefer having a schematic reference. I have run across errors in schematics for sure! nice to have the unit and schemo to compare!
I understand. But to be blunt, in this day and age there are more companies who copy schematics and put it out as products then companies doing original design. In fact some of our early group diy work was used by a few companies. It wasn’t supposed to be that way. But it happened. So I see why companies hesitate. To me an NDA really shows a you are serious about protecting their stuff and just fixing your stuff. I have a few with different companies for that reason.😎
 
I've watched significant changes in the audio markets over several decades.

What does it take to be a success (hint more than just a serviceable sku design)?

Ripping off other peoples designs is mostly short term thinking but I have seen some succeed at it.

JR
 
I am largely in support of sharing information, repair wise (right to repair), and keeping old equipment going that is no longer supported. Sad to know there is so much good info lost over the years.
Unfortunately, it’s not “lost”. It exists still.
 
I have experienced this exact thing... no longer do warranty work for companies, which is mostly test, make sure its deffective, and send them a new unit... or at best, board swapping..
Yes I can attest to that. My last stint the big thing was board swaps for field guys unless it was something super simple. Then the boards came back to the mothership for rework and back into the cycle of use for swaps. While this does expedite things, it really isn't a healthy option IMHO. The better option is field board repair if and when possible as it is the fastest way to resolve things.
 
Yes, but if you're sold on that old thing and you love it so much you can't live without it, then the manufacturer faces a choice between selling you a "new one" of the latest-greatest flavour (typically over 50% margin) or selling a spare module (a single PCB can easily be as much as 95% margin) ..... or making no money at all because, armed with the circuit diagram, you managed to repair it yourself or paid an independent repair house but either way, no revenue flows to the OEM. There's arguments for both sides, as an engineer I know ANYTHING can be fixed and having worked for equipment manufacturers for 40+ of years, I can tell you that'll be their (cynical) Policies. There are a couple of other reasons, mainly around (perceived) liabilities but the revenue one's the lynch pin.
 
Yes, but if you're sold on that old thing and you love it so much you can't live without it, then the manufacturer faces a choice between selling you a "new one" of the latest-greatest flavour (typically over 50% margin) or selling a spare module (a single PCB can easily be as much as 95% margin) ..... or making no money at all because, armed with the circuit diagram, you managed to repair it yourself or paid an independent repair house but either way, no revenue flows to the OEM. There's arguments for both sides, as an engineer I know ANYTHING can be fixed and having worked for equipment manufacturers for 40+ of years, I can tell you that'll be their (cynical) Policies. There are a couple of other reasons, mainly around (perceived) liabilities but the revenue one's the lynch pin.
I think it is important to distinguish between professional and consumer/semipro suppliers. The professional ones know their customers will want their gear to be earning as much as possible all the time and they cannot afford the time or effort to deal with sending items off for repair. It needs to be fixed now and that is why they have an on site service department who will make repairs. For this reason they provide full service info. For consumer/semipro, little if any of the above applies.

Cheers

ian
 
Lexicon and Eventide published schemos. While some/many failures on their products can be traced to analog I/O or PSU problems, good luck doing anything on the digital sections without service info.

Bri
Trying to repair a friend’s Eventide H910 was the most humbling thing I’ve attempted to fix. It took me less than an hour to figure out that the PSU voltages were all bonkers because the power transformer was wired for 220v, instead of 110. I corrected that and changed one of the regulators, then the power was normal, so I had high hopes that I got off easy. Nope. I pulled every one of the million tantalum caps to test them, poked around for a few days after that, and eventually gave up.
 
Trying to repair a friend’s Eventide H910 was the most humbling thing I’ve attempted to fix. It took me less than an hour to figure out that the PSU voltages were all bonkers because the power transformer was wired for 220v, instead of 110. I corrected that and changed one of the regulators, then the power was normal, so I had high hopes that I got off easy. Nope. I pulled every one of the million tantalum caps to test them, poked around for a few days after that, and eventually gave up.
What does (or doesn't) it do?

Bri
 
What does (or doesn't) it do?

Bri
It’s been a few years so I’m a bit fuzzy on what exactly it didn’t do, but I don’t think it had any effect at all and do remember that I had signal getting up to the digital section, and could inject signal into the exit and had signal on the output. In the digital section I did all the standard stuff like checking all the power pins on the chips, testing caps, feeling for an abnormally hot chip, testing for shorts, etc., but even with having the schematics I honestly don’t have enough knowledge to troubleshoot the digital circuit.
 
I think it is important to distinguish between professional and consumer/semipro suppliers. The professional ones know their customers will want their gear to be earning as much as possible all the time and they cannot afford the time or effort to deal with sending items off for repair. It needs to be fixed now and that is why they have an on site service department who will make repairs. For this reason they provide full service info. For consumer/semipro, little if any of the above applies.

Cheers

ian
I don't work with consumer grade or semi-pro manufacturers... When an end-user demands high system availability and or short MTTRs, then the response is to sell on-site spares holding to them (conveniently increasing the manufacturer's revenue). Faulty modules/units can then be managed as above, i.e. repairs are effected by the OEM using a return-to-base model.
 
A lot of valid reasons were written here but there was one very important reason for some companies not releasing Schematics that was not brought up.

Honest truth in the XXI century:
Companies don't you to repair their products,
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

The market and economics are completely based in planned obsolescence,
and actually a lot of failures of products were tested, or some parts of the circuit were designed with less quality companies so that they fail in a few years.
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

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

"Planned obsolescence describes the practice of designing products to break quickly or become obsolete in the short to mid-term. The general idea behind this is to encourage sales of new products and upgrades"
 
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A lot of valid reasons where written here but there was one very important reason for some companies not releasing Schematics that was not Brought up.

Honest truth in the XXI century:
Companies don't you to repair their products,
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

The market and economics are completely based in planned obsolescence,
and actually a lot of failures of products were tested, or some parts of the circuit were designed with less quality companies so that they fail in a few years.
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

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

"Planned obsolescence describes the practice of designing products to break quickly or become obsolete in the short to mid-term. The general idea behind this is to encourage sales of new products and upgrades"
But why would you buy a new product from the same company whose previous product failed before it should have ?

JR
 
But why would you buy a new product from the same company whose previous product failed before it should have ?

JR
If it fails during DLP, then it's repaired (or probably replaced) under warranty. From the manufacturer's point of view, failures beyond DLP are "acceptable", or perhaps intentional. Makers also monitor the incidence of warranty claims and use that data to tweak designs and or adjust their future warranty durations.

It's not exactly new science; Brunel was making pithy comments about it in the 19th Century!
 
If it fails during DLP, then it's repaired (or probably replaced) under warranty. From the manufacturer's point of view, failures beyond DLP are "acceptable", or perhaps intentional. Makers also monitor the incidence of warranty claims and use that data to tweak designs and or adjust their future warranty durations.

It's not exactly new science; Brunel was making pithy comments about it in the 19th Century!
"DLP"?
 
The advent of SMD components has sadly for many products brought them to a point where on board service is not deemed practicable and thus board replacement is the only service option - a lot of techs won’t do component level service as many LSI’s are too difficult to solder and/or they don’t want to tackle removal and replacement of the smaller IC’s anyway.
Some pro gear suppliers in this country have single city repair centres where the gear has to be returned to that city for warranty repairs, they don’t have repair centres in each state capital - makes it difficult for studios and gigging musicians who don’t have the luxury of a backup $5000 synthesizer or piece of rack gear - unfortunately the time people find this out is when the gear breaks down. The cost to ship a 20Kg keyboard from Sydney to Melbourne is pretty high - don’t throw out the box as it will cost you almost double to ship it in a reinforced flight case.
I do a lot of warranty work for some importers who supply multiple brands to retailers from a single-city distribution centre, as they have come to realise that without proper representation country-wide they are losing repeat customers and recommendation sales or retail outlets won’t sell the product and need to have service agents in other cities. These companies are good with schematics but there are NDA’s that are in place for the service documentation for many brands, so the schematics are likely never to see the light of day on the open net. A lot of gear has the service docs with test point checks to determine fault status and which board needs to be replaced - some list likely component failures with a cross check table.
Some will not release any documentation and rely on board replacement only service - the replaced boards becoming landfill. 😟
In many cases the cost to do on-board repair in labour exceeds the cost of a replacement board and is not supported by warranty.
 
The advent of SMD components has sadly for many products brought them to a point where on board service is not deemed practicable and thus board replacement is the only service option - a lot of techs won’t do component level service as many LSI’s are too difficult to solder and/or they don’t want to tackle removal and replacement of the smaller IC’s anyway.
Some pro gear suppliers in this country have single city repair centres where the gear has to be returned to that city for warranty repairs, they don’t have repair centres in each state capital - makes it difficult for studios and gigging musicians who don’t have the luxury of a backup $5000 synthesizer or piece of rack gear - unfortunately the time people find this out is when the gear breaks down. The cost to ship a 20Kg keyboard from Sydney to Melbourne is pretty high - don’t throw out the box as it will cost you almost double to ship it in a reinforced flight case.
I do a lot of warranty work for some importers who supply multiple brands to retailers from a single-city distribution centre, as they have come to realise that without proper representation country-wide they are losing repeat customers and recommendation sales or retail outlets won’t sell the product and need to have service agents in other cities. These companies are good with schematics but there are NDA’s that are in place for the service documentation for many brands, so the schematics are likely never to see the light of day on the open net. A lot of gear has the service docs with test point checks to determine fault status and which board needs to be replaced - some list likely component failures with a cross check table.
Some will not release any documentation and rely on board replacement only service - the replaced boards becoming landfill. 😟
In many cases the cost to do on-board repair in labour exceeds the cost of a replacement board and is not supported by warranty.
Most manufacturers of worth authorise and use third-party repairers to provide in-region representation if they don't have footprint in that geography - and you're right that with no warranty support, future sales suffer - but beyond once warranty expires, I can assure you that manufactures just want to sell new product.

Bearing in mind manufacturing GMs (gross margins), the economics of repairing a PCB/module/unit vs the true cost to the manufacturer to give away a new one, rather than having repairs effected will go in favour of writing off the faulty item because it's lower cost that way.

Once again, this isn't really a new approach and while SMDs do make it more fiddly (especially with my eyesight!) to perform component level repair, the view that it's "cheaper" to replace modules rather than having skilled field techs was starting to emerge (in the UK, at least) as long ago s the 1980s ... and quite probably before that.
 

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