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[quote author="Bear"]Deane Jensen made the 990 public domain. [/quote]

yep
and Bill Whitlock sent me an email back when there was TT and Group DIY Up-Dates and gave us a TIF file with his compliments.

he also said,
... Anyway, the .tif file is attached. Hope it gets to you and to the newsgroup. As you will note, the 990-C uses quite a few selected parts to keep offset voltage and distortion extremely low. Also note that Deane's patent involved the inductors in the input pair emitters. These are the key to solving a proverbial tradeoff between stability and slew rate - a very clever solution indeed.


Many thanks and best regards,

Bill
Click to expand...

I'm sure he would be happy for me to post that again. Bill is one of the old Friends of Group DIY and an interested DIY'er.
... more than just the interest in selling Jensen trafo's, which is something I am also interested in doing too.
hint hint - Bill are you out there ?
:thumb:
 
I think there are two factors at work here:

1. "Intellectual Property" ("IP"), including the legal protections that cover it. Much has been written about IP. There are over 15-million links on Google.

2. The "Just having some fun" factor. Taking things apart and putting them back together can be a whole lot of fun.

Deane Jensen declared the circuit of the 990 to be public domain, but I have not made any such declaration regarding the p.c. board designs that I have developed. The p.c. board design of the 990 has gone through many changes over the years. It started as a single-sided design in 1979 when the original 990 circuit was introduced. There were 41 components and six pins on a p.c. board that was about 1" square. In 1980 I made a major revision when I decided to move the output transistors and to mount them vertically instead of bending the leads at a 90-degree angle. An even bigger p.c. board revision was made in 1989 when the 990A and 990C circuit versions were developed by Deane Jensen and Steve Hogan. The 990C has 49 components. I moved the output transistors to the edge of the p.c. board so that they could be bonded directly to the aluminum shell that was added to the package at that time. This provided improved heat sinking and heat dissipation. This p.c. board design is double-sided. I have made several revisions to this design over the years to improve performance and manufacturability.

I think that my p.c. board design qualifies as "Intellectual Property", although I am not a legal expert. The design is unique and special, and not something that is easily arrived at without considerable research and development, trial and error, and the special knowledge that comes from experience, and so on.

I can appreciate someone's desire to take things apart to see how they work. There is much to be learned from doing so. Sometimes you learn the best ways to do things, other times you learn how NOT to do things. I have taken things apart and (usually) put them back together since I was a child, and I am now 57 years old. This is the "Just having some fun" factor.

But for someone else to take my intellectual property and turn it into any kind of profit-making venture is something that I would not be happy about. I don't know the legal issues, and I'm not even beginning to suggest that I would take any legal action, but morally I think it stinks for someone to take someone else's intellectual property and use it for profit.

To ijr: You do not have any claim or right to my intellectual property. It is not yours to disseminate to anyone else. I applaud your accomplishments, but I respectfully ask that you do not provide this intellectual property to anyone else, and that you do not use it for profit in any way, directly or indirectly. It would, at the very least, be disrespectful. It could also violate the law.

Thank you.

John Hardy
The John Hardy Co.
www.johnhardyco.com
 
Hello John!
Understood.
NO poll about interest in pcb's and NO sharing of layout.
Learned a lot from your pcb design, it is GREAT layout.
Electronics is art, what's more?
Now, I'm working on discrete opamp design based on
"common-base"amplification stage and using mosfet pair running
at fare high current at input, and have some problems with thermal stability. I going to try some things I've seen on your pcb design, is it OK?
Thank You,
Igor.
 
John is as cool as they get...

I just recently ordered some 990s for another project from John. I was surprised when he answered the phone himself! He took my order, and even chatted about his preamps with me for a while.

John is as nice a guy as they come, and a great asset to the DIY community. I only wish he had the time to have more of a presence around here. Certainly there's a lot we could all elarn from him.

Shane
 
[quote author="John Hardy"]
To ijr: You do not have any claim or right to my intellectual property. It is not yours to disseminate to anyone else. I applaud your accomplishments, but I respectfully ask that you do not provide this intellectual property to anyone else, and that you do not use it for profit in any way, directly or indirectly. It would, at the very least, be disrespectful. It could also violate the law.

Thank you.

John Hardy
The John Hardy Co.
www.johnhardyco.com[/quote]

See this is exsactly what I have been talking about..One should get a legal yes of the "owner" of the layout , pcb design etc before going out in public..and I will always speak for this as long as I´m around here and elsewhere ;-)

Thanks John for speaking up on this.

Kind regards

Peter
 
Ah Deane Jensen; look what you started by mischieviously designing that little black box! Shame!
And Bill Whitlock, how do you think you caused all those people who failed in acquiring a Patent for their electronic circuitry feel because you succeeded by designing this clever & unique circuitry ?
http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&u=/netahtml/search-adv.htm&r=72&f=G&l=50&d=PTXT&s1=Whitlock.INZZ.&p=2&OS=IN/Whitlock&RS=IN/Whitlock
Regards,
Tom
 
Guys, im really sorry if i started some bad vibrations. Last thing i wanted is to use somebodys intelectual property and make profit. I make profit from my songs, production, and preforming. Electronics is what i'm educated, but i turned in hobby, like DIY audio. So, if you sometime passing around (Belgrade), please be my guest, and let's keep this forum like have to be. Nice and creative :thumb: Long live DIY :guinness:
 
Hi John,

... another Friend of Group DIY.
:thumb:

In all seriousness John has blocks available for us to buy. They are developed and working up to spec.

For many DIY'ers the Melcor 1731 in it's various forms are enough for you to play with.
If you want to get 990c and other variants then develop your own layout make your own PCB. Some guys have already done that and they keep it to themselves.

I can tell you for sure they spent more time and money and effort to get the first working ... than to but a few straight from John Hardy. These guys are die hard and have the experience and skill to get throught it.

For the bulk of the DIY'ers here it makes more sense to use any of the existing units from John, Fred or Joe and package them in a box of two or four to suit you needs.

It would make more sense to me to put the word on John to present a Group DIY/LAB discount deal for JH 990's.
:green: :green: :green:
 
Hello John!
Understood.
NO poll about interest in pcb's and NO sharing of layout.
Learned a lot from your pcb design, it is GREAT layout.
Electronics is art, what's more?
Now, I'm working on discrete opamp design based on
"common-base"amplification stage and using mosfet pair running
at fare high current at input, and have some problems with thermal stability. I going to try some things I've seen on your pcb design, is it OK?
Thank You,
Igor.
Click to expand...

Igor; Thank you for understanding, and thank you for your compliments. Good luck with your new design. Just curious: What things that you saw on my p.c. board design are you thinking of trying in your new design?

John Hardy
The John Hardy Co.
www.johnhardyco.com
 
Hello John!
Really... these things are common in power amplifier's pcb design,
like putting Wilson's mirror far from output and glued together, putting
input stage's current source transistor far from out too, and
arrangement of output stage transistors/diodes, common power supply
points ("stars") right on PS bypass capacitors pads..
I have a question like "can I in case of whatever use more or less same parts arrangement like on your PCB if I do my own 990C pcb, does it crosses with IP legal issues?"
Sorry , my english is not very good...
(edited:grammatics too:)
Thank You,
Igor.
 
Igor;

There is a good saying regarding design (of any product): "Form follows function". The parts are positioned where they need to be to work the best. In an op-amp, the input pair of transistors is near the input terminals (Amazing, isn't it??). The two transistors that make the "input pair" are next to each other. The output transistors are near the output terminal. The parts that connect to the positive power supply tend to be along one edge of the p.c. board that is closest to the positive power supply terminal, while the parts that connect to the negative power supply tend to be along the other edge where the negative power supply is. Your examples are excellent as well.

Regarding the 990C p.c. board design specifically: On one hand, I would not want you to copy my layout. On the other hand, if you developed your own layout without ever seeing mine, it would probably have many similarities to mine. It is unavoidable if they are both good designs. There is another saying: "Great minds think alike" (although, it could be argued that one of us was actually thinking, while the other was just copying).

I think others have said (more or less) that the 990s that I build are priced low enough so that it doesn't even make any sense to try to build your own. There are other discrete op-amps that have less expensive parts but sell for a lot more money than the 990C. There are many construction details and special procedures that have been developed here that make my 990s better performers and more reliable than they otherwise would be.

Still, I can understand and appreciate the INSANITY that afflicts the people that are following this subject (myself included). Sometimes you just have to do it yourself. It is basic human nature. Even if it is not a financially sound decision, you just have to do it! "LOOK!!! I DID IT MYSELF!!!" (A sudden puff of smoke, a circuit breaker trips, your friends are snickering, etc.).

So, what to do? Perhaps you will develop a better layout. I have moved a few parts around (a little bit) with each revision, but I think the layout has been developed to where it is about as simple and efficient as possible. Any further revisions would be very minor.

Now that you have seen my layout, I would guess that it will be hard to make a new layout that is much different without hurting performance. So, it depends on what your plans are. For experimental purposes in limited quantities, I do not have a problem with you making 990C op-amps with a very similar layout. I think one of your earlier messages said something about building a console with the 990C being used in it in some locations. There is a general concept about "personal use", or something like that. As long as someone is copying someone else's product (or something like that) and it is only for limited personal use, it is acceptable. I think I would go along with that idea (I reserve the right to change my mind). I would definitely be unhappy if you passed the layout information to anyone else. That is a direct "IP" problem. I also suggest to everyone that it is not a very easy product to assemble because there are well over 100 holes in an area that is about 1" square. The solder pads are very small and fragile. This is one more good reason to just buy the finished product. If something goes wrong with it, it can be very difficult to troubleshoot the problem. With the very small solder pads, it is easy to damage the pads when trying to desolder and resolder various parts. I use a wave solder machine and a Q-Corporation lead-trimming machine to greatly enhance the quality level and the consistency. If you hand solder more than a few 990C modules, you will probably lose your mind completely.

I was going to suggest that you send images of the "new" layout to me personally (not on the forum), but then I could have "IP" problems in reverse!

How many 990C modules would you really like to build (without getting me mad)?

Thanks again.

John Hardy
The John Hardy Co.
www.johnhardyco.com
 
Just want to point that there is another 990 Layout that has been done sometime ago by one of the forum menbers, Dale. I think this one could be used freely.

Here is the link:

http://www.groupdiy.com/index.php?topic=1401&postdays=0&postorder=asc&start=15

BUT, $45 bucks for the JH 990 is very very nice price. I don´t know if I´m gonna ever DIY. I may just buy some assembled and tested JH990c.
 
I have been designing (trying anyway) my own discrete opamp for over a year with a FET input and BJT output. It is NUCKING FUTZ hard to get it right!
There is a lot of hard work that goes into a good quality discrete opamp, and the JH990 is as good as it gets.
I know you look at it and say "there must be about $15 of parts in it only". Perhaps, but those parts have to be purchased in large quantities then sorted and matched. Some things are expensive even when you get a hundred of them like that nice metal potting case ($4 in qty. 100). Unless you are wealthy you will be buying things on credit and pay interest. That has to be recovered at the end of the month/year.
By the way, there is cull, or a certain percentage of units that will not work. Fixing them is almost a complete waste of time unless you are an unemployed DIY-er. You have to recover your cost by selling the working ones for a little more.

Technically, there is a good reason why these products are expensive and I just wanted to give you a few to think about.

(DIY != Business) && (Business != DIY)

Cheers
Tamas
 
Thanks John.

I think it is worth reading Johns post a couple of times as there are little gems of wisdom in there that apply to much of our DIY projects.

I'll just summarise a little,
"Form follows function".
... without ever seeing mine, it would probably have many similarities to mine.
"Great minds think alike"
"LOOK!!! I DID IT MYSELF!!!" (A sudden puff of smoke, a circuit breaker trips, your friends are snickering, etc.).

I like this one and although it has never happened to me ... I have had an engine expire at full throttle when a valve and valve guide didn't quite do the right thing.
right when everyone was watching ...

I also suggest to everyone that it is not a very easy product to assemble because there are well over 100 holes in an area that is about 1" square. The solder pads are very small and fragile. This is one more good reason to just buy the finished product.

Once you have made a couple of Melcors for yourself why bother going to all that trouble for subsequent projects when there are some good ready to go options.
I did get a few Melcor PCB's but tis was mainly driven by my wish to support the forum and the Group DIY web page and hand out freebies to people that come to my place in person. Like the SSL PCB's and VCA's.

The forum should bend the ear of these DIY friendly guys and try to set up a discount or multiple deal sort of thing and mostly the forum should support these guys so they can be hear for years to come and continue to help us and the new DIY'ers of the future.
 
How many 990C modules would you really like to build (without getting me mad)?
Only 36 and maybe some spares if I still will have thermal problems with my opamp.
Or just two as I have at this moment if not.
Really, thing started from equal loudness test of MM, new 2520 and 990c
at equal loudness test under condition (20 db of attenuation then 20
db of gain) from tested opamp with dc sevo... 990c was best at all.
My friend had 990c that blow out....
Now, for me making 36 of 990's or other discrete opamps
is not madness, but just a way to learn how things working.
Also...wave soldering machine is another fun to spent some
"pocket money" :))
@Tamas: I have some time to spent on DIY. It is allmost impossible in
Israel, but my work takes 4-7 hours per day, as repairman I relatively fast. (I hate per-hour job).
I never sold and never will sell not mine designs.
This is mine, for example. Things like this covers my DIY too.
http://www.geocities.com/igor_jazz/mast_comp.html
BTW, tube based vca can work from dc to some hundereds Khtz
and have cv breakthrough ~-40-50 db at 10Khz normal case.
This is DIY business.
Seliing "g1176" to friends, sorry, not mine job.
Click to expand...
 
Hi Mesmer!
Laser engraving machine...
Once, company called Sharplan closed one of theirs branches
(due to and economical problems caused by intifada like 2-3 years ago).
There was gigatones of laser stuff on one surplus place,
try to imagine 30 or 40 laser plastic surgery, dental surgery
machines and 3-4 tones of co2/ss lasers, power supply's, optics....
I don't need to say some people did some money on it.
I bought dental co2 laser machine with 50w laser tube.
(actually, laser's power supply was limited to 15W) and some optics.
Laser's tube power supply was not made to work continuously
and blew out after first hour. I built mine and get ~30w output.
Connected optics to a3 plotter and that's all.
After some time, I built cnc machine (actually, used existing x/y
table and added z axe, and make drivers and other electronics).
This thing can do even big dualsided boards for first prototypes
and square holes in front pannels, and M* kinda looking engraving.
Some time ago company I work as repairman started to get some
non-audio works, like building of first prototypes for God-know-what
purposes, ultrasound stuff &etc.
This allowed me to bring these machines.
What to say more, audio in Israel
is not a way to make big money....
 

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