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Old 10th September 2012, 04:04 PM   #871
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Only thing I can say is as long as I can still purchase 60/40 flux core solder I am going to use that for myself. Now a commercial manufacturer can't do that but as a DIY builder I will stay with what I know works and actually flows well while not working with surface mount devices. I would think that in a commercial situation we have metallurgists that can handle all the problems that are being spoken of and I would sure think that with the millions of computers being built that this problem has been looked at thoroughly on the grand scale. But for me right now Viva La Fry's Electronics and lead solder.
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Old 10th September 2012, 04:25 PM   #872
bcarso is offline bcarso  United States
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Only thing I can say is as long as I can still purchase 60/40 flux core solder I am going to use that for myself. Now a commercial manufacturer can't do that but as a DIY builder I will stay with what I know works and actually flows well while not working with surface mount devices. I would think that in a commercial situation we have metallurgists that can handle all the problems that are being spoken of and I would sure think that with the millions of computers being built that this problem has been looked at thoroughly on the grand scale. But for me right now Viva La Fry's Electronics and lead solder.
Don't count on the computer industry solving the problems, since rarely are the machines regarded as "mission-critical". In fact a cynic would suppose the manufacturers might be just quite happy to have whiskers grow after a couple of years, necessitating replacement of the machine.

I've seen some remarkable evolution in my lifetime of ways things are put together. As a child, tube circuitry with terminal strips and point-to-point wiring, to printed wiring boards with plenty of spacing for the discrete components, and other schemes like "cordwood" modules with welded leads; the introduction of integrated circuits with lead pitch of ~2.5mm (my father thought those impractical because far too small). The shift from manual soldering to wave soldering, finally reflow, and of course the ever-smaller dimensions.

The biggest problem for some of these was flux contamination, failure to either clean the flux or have the process tuned properly for it to fully evolve. And of course the raw board fabrication had to be very good to avoid underetching. At one point the very manufacturing-dominated cultures were issuing edicts to the designers about the highest impedance permitted! I think at Harman, at one point, the highest resistance was supposed to be 10k!

Now we have the hazardous materials reduction initiatives and a whole new set of metallurgical issues, while the geometries shrink more and more. It's no wonder that systems-on-a-chip or multichip modules are popular.
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Old 10th September 2012, 04:32 PM   #873
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bcarso,
I understand all of your concerns. But I know I have been reading about this situation for many years in my NASA Tech Briefs and it would seem that the changes from lead solder to lead free have been researched for many years by some pretty smart people. To say that these metallurgist don't care about what you are sighting would just seem silly. There are many critical computer applications in everyday use and also on satellites that just can't be allowed to fail because of poor solder connections. Now Toyota, that is another story, cheapest vendor wins in that one...
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Old 10th September 2012, 05:06 PM   #874
bcarso is offline bcarso  United States
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bcarso,
I understand all of your concerns. But I know I have been reading about this situation for many years in my NASA Tech Briefs and it would seem that the changes from lead solder to lead free have been researched for many years by some pretty smart people. To say that these metallurgist don't care about what you are sighting would just seem silly. There are many critical computer applications in everyday use and also on satellites that just can't be allowed to fail because of poor solder connections. Now Toyota, that is another story, cheapest vendor wins in that one...
Not claiming the issues aren't understood, just not applied. To satellites, yes (although note that military and others get exemptions to use lead etc.).

Toyota is one of the very tragic examples of a first-rate quality-oriented culture deteriorating. Automotive is emphatically not cheapest-vendor oriented (unlike most of consumer and consumer-computer business lately, another whole tragedy) but if they are following the QOS directives, suppliers have to be elaborately qualified. It took Harman many years to get the Toyota and eventually Lexus business, and the Toyota folks were extremely demanding, at least in those days.

Of course things are always cost-sensitive in automotive. But once you are awarded the business, you won't walk in to the plant one day and find the customer has gone across the street for their stuff because it's a nickel cheaper. Gregg Stapleton knew how to play the chess game and win. He told me once that everyone said automotive was just too cutthroat and as well so demanding of highest quality, and not to even attempt it. But it was and remains afaik the most successful activity of Harman.

It didn't hurt that the premium automotive sound systems were part of a large final vehicle cost, and if you were spending, say, 45k, a 3k adder for the top-of-the-line system could be absorbed without too much pain.

Brad
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Old 10th September 2012, 05:34 PM   #875
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Scott... I'm back... any more work on making that output stage work at its best and on its best behaviour?
-Dick
[ I and several others have used it as shown with No issues. so maybe its ok?]
No news, how about THD @ 20k? with level. I'll be busy for a few days.
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Old 10th September 2012, 06:33 PM   #876
RNMarsh is offline RNMarsh  United States
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No news, how about THD @ 20k? with level. I'll be busy for a few days.
OK
Sure. THD at 20Khz with level is good.
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Old 10th September 2012, 06:34 PM   #877
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Bcarso,
As a former vendor for JBL/Harmon I have to disagree with you vehemently. They will leave a vendor in a second if they think that they can save a dime somewhere else. Been there and done that with them. They actually went around the country trying to find a cheaper source after we did all the design and development and met their extreme quality standards. They just wanted a cheaper price. Believe me when I tell you that the other vendors took one look at what we were doing and didn't have a clue how we were producing the part, I knew most of the other vendors and they just turned JBL down flat. Our biggest problem was that we had to work with parts coming from JBL themselves, their internal quality control was terrible and we had to charge them many times to rework their own work rather than lose time waiting for them to fix their internal production problems. I met more than one of their senior buyers and this was a constant quest of theirs to lower prices above much else, though they would still demand the highest quality. Most of the production that is coming out of Harmon is made in China by the lowest bidder that will meet the quality standards, that is the model, that is why nothing is being made here, cost of production was very high on the list. The cost of marketing was often higher than the price of goods, don't get that backwards. My neighbor was very good friends of Sydney Harmon until his death, he was a consummate business man ahead of most other things.
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Old 10th September 2012, 07:31 PM   #878
bcarso is offline bcarso  United States
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Bcarso,
As a former vendor for JBL/Harmon I have to disagree with you vehemently. They will leave a vendor in a second if they think that they can save a dime somewhere else. Been there and done that with them. They actually went around the country trying to find a cheaper source after we did all the design and development and met their extreme quality standards. They just wanted a cheaper price. Believe me when I tell you that the other vendors took one look at what we were doing and didn't have a clue how we were producing the part, I knew most of the other vendors and they just turned JBL down flat. Our biggest problem was that we had to work with parts coming from JBL themselves, their internal quality control was terrible and we had to charge them many times to rework their own work rather than lose time waiting for them to fix their internal production problems. I met more than one of their senior buyers and this was a constant quest of theirs to lower prices above much else, though they would still demand the highest quality. Most of the production that is coming out of Harmon is made in China by the lowest bidder that will meet the quality standards, that is the model, that is why nothing is being made here, cost of production was very high on the list. The cost of marketing was often higher than the price of goods, don't get that backwards. My neighbor was very good friends of Sydney Harmon until his death, he was a consummate business man ahead of most other things.
I didn't say Harman per se, I said Automotive! Not JBL Consumer, not even JBL Professional, not most of the other far-flung divisions. Automotive at least used to be very, very different. The other business divisions, despite their pretense to it when it serves them, do not follow the Quality Operating Systems that at least used to be de rigueur for automotive (i.e., Harman-Becker). Yes, for the others, pretty much anything goes. Background: I worked for automotive for about 4 years, 1990-1994, when I quit to become a consultant and therafter worked primarily for the Multimedia folks, until I was shown the door in Dec. of 2004 (and I haven't been back through that door since).

I knew Sid as well, although I was never one of the inner circle. Please honor his memory by getting the spelling of his name correct

Brad Wood

Last edited by bcarso; 10th September 2012 at 07:38 PM. Reason: spelling correction
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Old 10th September 2012, 07:42 PM   #879
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Brad,
I remember the Becker name well and this must have been pre-Harmon as it was long ago. One of the nicest sounding radios in a car back then, as long as you were sitting still. Mercedes Benz 450SEL... sorry about spelling Sid's name wrong, nobody said they taught us English that well here in California..... yes my neighbor was one of the inner circle of friends. One of my early waveguide designs was copied and that became the first generation EON pro-audio speaker.
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Old 10th September 2012, 07:55 PM   #880
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Brad,
I remember the Becker name well and this must have been pre-Harmon as it was long ago. One of the nicest sounding radios in a car back then, as long as you were sitting still. Mercedes Benz 450SEL... sorry about spelling Sid's name wrong, nobody said they taught us English that well here in California..... yes my neighbor was one of the inner circle of friends. One of my early waveguide designs was copied and that became the first generation EON pro-audio speaker.
The name is Harman, Sidney Harman. Shaken, not stirred --- no, wait, that's something else.

Once the Northridge group got an entire set of HealthNet ID cards with the spelling wrong (Harmon instead of Harman). They had to take them all back
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