Discrete Opamp Open Design

rendering drawings in cad? honestly if you have enough ram, the operation should be all loaded and performed in ram anyway, cant see how it would be much faster. where SSD shines is loading apps, start up, shutdown, anything that requires reading and writing large continuous files like video editing, audio production etc. cad will be faster, but not that much. for the things where its used OMG insanely fast

I run a 6g OWC raid class SSD and so far (about 12months) its safe as houses 5 years warranty. its just system and applications, plus any project files i'm working on, everything else is on HD

Kindhornman, no need to run virtual windows these days, you can run it natively on the mac if you really want, no emulation, we use the same chips these days. you can run emulation if you like and have both loaded simultaneously, but you can also run dual boot with either natively. only computer you can run all systems on natively afaik
 
Last edited:
Scott, I noticed that. I wonder how it would measure with complementary parts?
Your choice of the BF862 was a good one, though, if you can use it.

The idea was something that could fit on a very small card that folks could use like the discrete op-amps that sell for a large premium over the BOM. Not for everyone and certainly no threat to your customer base, if you will a creative c0mmons circuit.
 
qusp,
Yes your right I should just put a partition on my daughter's Apple 27" Imac, only thing is it is a couple of years old and they chose the cheapest i5 intel chip for those machines, two cores but only two threads are implemented. My laptop with the i5 runs circles around that implementation. I couldn't believe it until I tried that and you can see now many cores are running. Half the speed of my HP 17" Envy laptop, truly a shame that they did that. Much better graphics though on the Apple, just bad implementation on the board. And my Seagate HDD's are also 5 year warranty, only thing is I just had one go down that was only about a years old....... My laptop has faster drives at 10,000 rpm than my desktop... And don't ask me why but Solidworks does use the hard-drive for many of its functions and I have 6GB of ram.

Time to build a new machine with more ram, 15,000 rpm SCCI hard drives and a nice new GPU with more ram. Perhaps some Xeon CPU's would be nice
 
Last edited:
Disabled Account
Joined 2012
rendering drawings in cad? honestly if you have enough ram, the operation should be all loaded and performed in ram anyway, cant see how it would be much faster. where SSD shines is loading apps, start up, shutdown, anything that requires reading and writing large continuous files like video editing, audio production etc. cad will be faster, but not that much. for the things where its used OMG insanely fast.

Opening folders one after another as fast as you can type and having large multiple files running at same time is awesome. Just d**n expensive -- having the HDD factories shut down forced this option..... I was in Thailand during the floads! 60 million cubic meters of water heading my way.... Bangkok. Got out just before the last airport got floaded out. Or Id be there for a long time -- and the thought of running out of food isnt a pleasant one. Panic was starting to be seen. -RNM
 
Wasn't it here on DIYaudio that someone posted NASA's analysis and conclusion of the Toyota accelerator problem? It was tin whiskers on the potentiometer connection of the accelerator pedal, one place they SHOULD have used old-fashioned tin-lead solder instead of the RHOS lead-free stuff that had already been known for years to generate tin whiskers.
Yes, that was me. There are exemptions to RHOS for mission critical, industrial controls, flight hardware, medical hardware...Perhaps the braking system of a car should have been deemed "mission critical"?

Russian Phobos-Grunt failed an year ago, supposedly because of electronics. It was a space ship that had to take soil probe from Phobos, Mars's satellite, and bring it back to Earth. Could it happen because of ROHS regulations?
Yes.

The NASA Cassini probe had a whisker problem a while back, the engineers thought about that for a long time, then determined that the electronics would be capable of clearing the whisker under power. So they did it about half a year ago IIRC, and the probe was able to continue functioning.

My biggest concern is the pure tin plating on discrete components. From what I also remember, conformal coatings don't necessarily stop whisker growth.

jn
 

Very nice, thanks.

Their discussion of temperature as being a process variable which has a large impact is very consistent with my experience.

Several questions pop up from that paper.
1. What are the alloy melt temperatures? I didn't see them listed. At a specific temperature, a lower melt alloy will scavenge at a faster rate, and I didn't see that accounted for in my quick review.
2. Flux activity is highly dependent on temperature. That's why fluxes in home depot were being labelled "lead free", not because there was no lead in the flux, but because it would work at the temperature range of lead free solders.
3. I recall many whisker questions from years ago..it was not known at the time if any additional metals could be added to the mix to prevent whisker growth the way lead did. It would be great if they tested whisker potential with the newer alloys.

The other tin problem is "pest". At lower temperatures, tin will turn to powder, I believe it was an atomic lattice change responsible. Tin silver eutectic does NOT have this problem( but pure tin plating will}.

I have a ton or two of 96/4 at cryo temps, and the solder joints are still good after 15 years.

jn
 
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.
 
diyAudio Member RIP
Joined 2005
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.
 
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...
 
diyAudio Member RIP
Joined 2005
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
 
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.
 
diyAudio Member RIP
Joined 2005
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 :D

Brad Wood
 
Last edited:
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.
 
diyAudio Member RIP
Joined 2005
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 :)