Schematics and knowledge sharing thoughts

[Newmarket]

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

JR

Good Question. They do though. Various permutations of reasons as I have observed and discussed ime. Product familiarity / industry standard (IBM effect) ; acceptance as industry norm; and - daft as it might sound - "we already have an account with them and don't want to increase vendor count".

 

[RoadrunnerOZ]

I have purchased cheap-end power tools working in the boatbuilding environment as the rapidity of epoxy buildup made expensive tools a very costly exercise - the cheap power drills, angle grinders, jigsaws and belt sanders I could blow 4 or 5 of these to equal the cost of an expensive tool which would go anyway at around the same time. Even though the cheap tools failed eventually some outlasted their more expensive counterparts. Go figure…..

 

[gyraf]

So.. you're saying that in an extremely high-wear environment, early failure is not necessarily a reason not to buy again.

Like among musicians....

 

[TLRT]

A company with a name related to heat refuses to share their schematics which is pretty funny.

Had a fairly new but noisy 76 from them in (which is maybe a rev D 1176 but with a BA283 style line amp? maybe?) -- turns out the BC184C transistors in the output stage were sketchy which is no surprise considering they've been obsolete for a long time (counterfeits? re-labeled mystery Chinese part?). Replaced with MPSA18 -- problem solved.

More importantly: the "Rubycon" capacitors in the unit looked preeeettyyy weird! The printed sleeves don't look remotely like any authentic Rubycon YXA caps I have ever received from Mouser or Digikey. Perhaps they should look into where their factories are sourcing these components.

When I contacted them for schematics or sevice info, they kind of just hinted at the fact that I should look up a stock 1176 schematic and figure it out from there lol... even though that isn't what their product is.

I can recognize this unit, and I have all the schematics(I do the local repairs for this brand

 

[RoadrunnerOZ]

So.. you're saying that in an extremely high-wear environment, early failure is not necessarily a reason not to buy again.

Like among musicians....

Basically yes - I had a $29.95 battery drill which I bought as a chuckaway - it outlasted all the other guys on the boatbuilding teams Makita, Bosch, AEG etc even after a 7 metre drop onto a concrete floor it still worked - replaced the brushes and that’s about it. I still have the same philosophy about things that are high usage and wear - if you can get 5 for the price of 1 and they all have a 2 year warranty, that’s 10 years of usage with no repair bills (unless you abuse the item), compared to a high ticket purchase that may last 5 years but you have to pay for repairs after 2. Working recently in the luxury auto industry I found the workshop was sending off buffing tools etc. for repairs which cost more than buying a cheaper tool and either throwing it out or getting it repaired way cheaper as the parts were so much less expensive.

 

[SoundBlaster]

Those are both from before my time working there, so pre-1985. The one on the right used technology that was still in use when I arrived. The chassis used a single sheet of vinyl coated steel that was punched and silk screened in the flat before bending. The one on the left is much older using flat panels and extrusions to deal with chassis surface angles.

Even those are not the really old Peavey Festival mixers, the early stuff used rotary knobs for channel faders. Those both look like pretty similar in form and features, powered mixers.

JR

I've been involved with the offshoring of products to China since 1995. We moved manufacturing from the US to China and quality IMPROVED!. it was better, cheaper and more consistent. There's a lot said about the quality of Chinese made products. We must also consider that they will build exactly what you are willing to pay for. A lot of American companies simply took the opportunity to make the most profit in the short term. Pay for poor quality, and blame it on China. It's not them, it's simply American corporate greed.

 

[JohnRoberts]

I've been involved with the offshoring of products to China since 1995. We moved manufacturing from the US to China and quality IMPROVED!. it was better, cheaper and more consistent. There's a lot said about the quality of Chinese made products. We must also consider that they will build exactly what you are willing to pay for. A lot of American companies simply took the opportunity to make the most profit in the short term. Pay for poor quality, and blame it on China. It's not them, it's simply American corporate greed.

As with all manufacturing you get what you manage. I was personally over there around that same time (mid 90s). Peavey hired one full time employee based in Hong Kong to provide same time zone factory support with a handful of contract manufacturers. Efficient production can't shut down and wait overnight every time there is a question.

I wouldn't automatically blame it on greed, many manufacturers had no other choice to remain price competitive in the market that was already filling with Chinese made SKUs. Lots of offshoring problems came from incomplete factory process documentation, including vague component specifications. Chinese contract manufacturers can find parts too cheap to work if allowed to.

JR

 

[SoundBlaster]

As with all manufacturing you get what you manage. I was personally over there around that same time (mid 90s). Peavey hired one full time employee based in Hong Kong to provide same time zone factory support with a handful of contract manufacturers. Efficient production can't shut down and wait overnight every time there is a question.

I wouldn't automatically blame it on greed, many manufacturers had no other choice to remain price competitive in the market that was already filling with Chinese made SKUs. Lots of offshoring problems came from incomplete factory process documentation, including vague component specifications. Chinese contract manufacturers can find parts too cheap to work if allowed to.

JR

Totally agree.. There can be a lot of looseness around parts quality.. Hell, I think some passives are essentially free! and the most expensive thing is the one you pay nothing for.. On the other side. They can build you some outstanding products if they're well specified and you're willing to pay for it.

 

[kidb]

I suppose this boils down to, there are legitimate reasons for some wanting to withhold schematics and keep information from techs. The more baffling ones are the clones of pre existing classic gear with schematics freely available of the vintage units, but said companies withold the schematics of the clones. I really don't think there is anything worth witholding from an api or neve clone..
NDAs should work in tricky situations. The other side of the coin for me is techs sharing their "discoveries/knowledge" which doesn't seem to happen very often irl, these forums are a slightly different story, but I know plenty of techs who do not get on forums or share what they know.
I feel like as a repair tech, I should save some of you from running in circles with issues I've already figured out. Working on that!

 

[JohnRoberts]

Totally agree.. There can be a lot of looseness around parts quality.. Hell, I think some passives are essentially free! and the most expensive thing is the one you pay nothing for.. On the other side. They can build you some outstanding products if they're well specified and you're willing to pay for it.

I'm cheap but I have typically been willing to pay a penny here or there for better quality components based on experience. Back in the 70s I was impressed by Rohm carbon film resistors that could just about turn red hot and return close to their original resistance value (I know not a fair criteria). I was happy to find that Peavey was already using Rohm resistors, but finally in the late 90s near the end of my time there, they got replaced by a cheaper vendor.

Peavey corporate cost saving suggestion programs caused an incessant parade of buyers in purchasing trying to get engineering to approve specifying in a new vendor to save a fraction of a penny each. When using millions (actually more?) each month it adds up. I insisted on a substantial factory test of the new resistors and the factory blessed them so I demurred.
====
Back on topic of repairing gear without schematics my sweet (20 years older than me and now RIP) neighbor from across the street, had a battery powered mobility scooter that was constantly breaking down. Even worse he would try to fix it himself first. I was able to find documentation for several versions of the scooter when it broke, one time I had to repair the battery charger that was not charging. The scooter was perhaps copied from a credible original western design, the battery charger not so much, at least not a good copy that used dodgy components.

These things are not rocket science and I figured out the basic circuit. The fault turned out to be caused by a bad 1/4W carbon film resistor that measured nowhere remotely close to its marked resistance. I didn't have the exact resistor value in my spare parts bin, but had one that was within about 20%. I don't recall if the resistance was high or low, but it was close enough to get the battery charger circuit working adequately again. I miss that neighbor, but don't miss having to repair his mobility scooter every several months or so.

JR

 

[Newmarket]

A few things to consider here. Obviously legislation will vary depending on location.
But - any reasonable person would support a "Right to Repair" approach. Where a product is supported by the manufacturer then that may justify protection of technical data - although that should be subject to regulation such that eg costs of repair are not extortionate or unrealistic.
Where a product is no longer supported then full technical information required for repair should be freely available.
And where a manufacturer simply no longer exists it should be mandatory that such information is made freely available.

 

[JohnRoberts]

And where a manufacturer simply no longer exists it should be mandatory that such information is made freely available.

If the manufacturer no longer exists, who you gonna call?

JR

 

[Newmarket]

If the manufacturer no longer exists, who you gonna call?

JR

In UK terms it would/should be part of any administration/liquidation process. Legal liability would fall to the officers of a limited company else the registered traders.

 

[Spack]

It is good training to repair equipment without schematics. In fact many old hand drawn schematics have errors that require figuring it out in real life.

Equipment designers who do novel designs (not copycat clone makers) have a valid concern about getting their best ideas ripped off. I have even had patented design ideas ripped off.

JR

It is good training to repair equipment without schematics. In fact many old hand drawn schematics have errors that require figuring it out in real life.

Equipment designers who do novel designs (not copycat clone makers) have a valid concern about getting their best ideas ripped off. I have even had patented design ideas ripped off.

JR

I’m with kidb. We’re way past need or interest in training. This is about getting things done and making a profit. Doesn’t matter how experienced you are…. Without schematics your just wasting more time than you need to

 

[JohnRoberts]

I’m with kidb.

this kidb? https://groupdiy.com/threads/schematics-and-knowledge-sharing-thoughts.88640/post-1168269

We’re way past need or interest in training. This is about getting things done and making a profit. Doesn’t matter how experienced you are…. Without schematics your just wasting more time than you need to

Have you ever wasted time trying to follow a hand drawn schematic with mistakes?

JR