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Post by chrisburrell on Nov 30, 2010 11:41:54 GMT
Naah then! How about making a replacement polycom card? It can't be that hard to do using surface mount transistors. Come to that it ought to be straight forward to make a surface mount card for the whole of the bottom three boards. It's not just me, there are others out there that love these machines... so... would I be speaking completely out of turn to even dare to suggest the slightest possiblilty of... making a completely re-vamped polymoog? All new parts, all new board(s) (smaller for a start so they don't flap around and break themselves).. but not straying from the original design so it sounds the same. It would use the same switches, display, case, keyboard and so on - so you wouldn't know.. but under the hood... It could use standard CMOS ICs just in TSSOP packages which are about 1/5 the size of a DIL package.. OpAmps are also available TSSOP and transistors and diodes etc are way smaller than anyone ever dreamed of in the days they were made. I have the feeling that it could be done on a single board (possibly two) so the Keyboard just wires straight across.. controls could wire straight across too. Could even put a switch mode power supply on the same board. Suposing I made one, would any one else be interested? Chris
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gt
Prodigy
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Post by gt on Nov 30, 2010 18:25:09 GMT
I'm with you on the Polycom card replacement. Sounds as though you've reverse engineered it or maybe you have a datasheet. A soundalike would be very welcome. In the spirit of the thread, does anyone know the failure pattern of these things? Is there a bathtub curve? If so there could be quite a demand in the future. As far as the PM on a board idea, personally keeping as much as poss of the original going is one of the attractions. ( or is that just me?) A bit like restoring a vintage car by reusing the original parts versus putting a chevy engine in it
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Post by Polymoog Lover on Nov 30, 2010 19:57:20 GMT
I with you guys all the way on this one. If only Moog Music was.....
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Post by nervejam on Nov 30, 2010 20:03:20 GMT
Naah then! How about making a replacement polycom card? It can't be that hard to do using surface mount transistors. Come to that it ought to be straight forward to make a surface mount card for the whole of the bottom three boards. It's not just me, there are others out there that love these machines... so... would I be speaking completely out of turn to even dare to suggest the slightest possiblilty of... making a completely re-vamped polymoog? All new parts, all new board(s) (smaller for a start so they don't flap around and break themselves).. but not straying from the original design so it sounds the same. It would use the same switches, display, case, keyboard and so on - so you wouldn't know.. but under the hood... It could use standard CMOS ICs just in TSSOP packages which are about 1/5 the size of a DIL package.. OpAmps are also available TSSOP and transistors and diodes etc are way smaller than anyone ever dreamed of in the days they were made. I have the feeling that it could be done on a single board (possibly two) so the Keyboard just wires straight across.. controls could wire straight across too. Could even put a switch mode power supply on the same board. Suposing I made one, would any one else be interested? Chris Go for it! I'd be interested (costs permitting). You could buy a knacked Poly, and do a straight transplant.. Or build something original.. Three-octave mini-poly, maybe!
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Post by spoonz on Dec 1, 2010 0:25:49 GMT
It would be an interesting project but i don't think it has legs commercially. Maybe the Polycom cards might.
Many Polymoog owners want them as original as poss (me included) and they aren't that bad once you iron out the bugs. If i were gigging or wanted total reliability i would buy one of the modern synths that do the sound almost as good as the original. Obviously there will come a day when original parts are no more but were not there yet. I can also say having restored at least 1 Polymoog with almost all new Ic's where poss with modern equivalents that it lost something. it was too tight and clean. Stable yes i'll grant you that. Essentially i don't think you can produce a modern Polymoog technology wise that doesn't sound very much like the best of what is already available digitally (Oasis etc). Synthrestore marketed a modern divider board that never really sold and he pulled it.
Go for it if you have the time as it will be an interesting ride and i hope it comes up trumps but for me doing it to my Polymoog would be like Pimping up my ride. I can accept it's old blown IC to keep it as original as poss.
GT - PM sent
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Post by brassteacher on Dec 1, 2010 2:38:31 GMT
Naah then! How about making a replacement polycom card? It can't be that hard to do using surface mount transistors. Come to that it ought to be straight forward to make a surface mount card for the whole of the bottom three boards. It's not just me, there are others out there that love these machines... so... would I be speaking completely out of turn to even dare to suggest the slightest possiblilty of... making a completely re-vamped polymoog? All new parts, all new board(s) (smaller for a start so they don't flap around and break themselves).. but not straying from the original design so it sounds the same. It would use the same switches, display, case, keyboard and so on - so you wouldn't know.. but under the hood... It could use standard CMOS ICs just in TSSOP packages which are about 1/5 the size of a DIL package.. OpAmps are also available TSSOP and transistors and diodes etc are way smaller than anyone ever dreamed of in the days they were made. I have the feeling that it could be done on a single board (possibly two) so the Keyboard just wires straight across.. controls could wire straight across too. Could even put a switch mode power supply on the same board. Suposing I made one, would any one else be interested? Chris Chris, I don't have the slightest doubt at all that you have the skills to pull this off. However, at least consider a couple things, some of which have been alluded to by others here. 1. Some have already noticed that modern versions of older parts sometimes have a different sound. There are many reasons for this, but I imagine the more complex, i.e., more parts a piece of gear has, the cumulative effect would be harder to overcome. That said, a very simple circuit, with very few parts, such a difference in semiconductors is all but impossible to overcome. For example, I've designed and built (and hope to market someday soon) a fairly successful high-end stereo preamp for home audio use. Without giving away too much, it uses so few parts that two different versions of the same, current production semiconductor have a slight, but noticeable effect on the clarity of the signal. The difference between the two? Same die for the chip, but one is a regular 8-pin DIP, and the other is in a metal can (TO-99). The TO-99 version is slightly more quiet. It is much less susceptible to vibration, and is much better shielded from EMF/RF interference. 2. I'm currently working on something, mostly for fun and expanding my knowledge, on a kit for one of the many attempts to clone the Roland TB-303. In that community, the holy grail is to build something that is indistinguishable in sound from the original. This particular one goes as far as to not only clone the analog section of the synth part-for-part, but the original run of the kits had sourced NOS versions of EVERY semiconductor in the beast (well, except for one). Even with all of the active components in the analog section being either NOS or sourced by salvaging them from vintage gear, the thing STILL sounds slightly different. I'm trying the probably impossible task of trying to find modern transistors that will sound either the same, or not enough different to worry about. The TB-303, like the Polymoog, uses quite a few components that have been long obsolete. Thing is, something as relatively simple as the TB-303 has been proven amazingly difficult to clone, and it is far more simple than the Polymoog. 3. I've worked on enough vintage gear, both at home and in a few repair shops, that with something that is a vintage musical instrument or even a vintage musical instrument amplifier, you don't DARE change any of the original parts unless absolutely necessary, and when necessary, you try to find a part that is as near to the original as possible. For instance, a friend once repaired a vintage guitar tube amp, and decided to upgrade the old, drifted resistors in the amp with nice modern metal-film types. The amp owner was back in the shop a couple hours after picking the amp up, and was quite explicit on not only which parts of my friend's anatomy he was going to remove, but also the method, if the original resistors were not replaced immediately! I don't want to discourage you, in fact, not only would I like to see it done, I'll gladly help out. That said, I hope the task does not turn out to be impossible, or nearly so. They've been working about 10 years on that TB-303 clone, and still can't claim it to be impossible to tell from the original.
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Post by Polymoog Lover on Dec 1, 2010 22:51:01 GMT
I think it would be awesome if we could just take the engine from the unreleased VSTi (I mean, that thing IS a Polymoog) and just put it into a REAL Polymoog's chasis. That way, you'd have a completely reliable, digital (but still unmistakably Analog-sounding) gig-worthy clone. Sigh, I can dream....
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Post by nervejam on Dec 2, 2010 8:45:59 GMT
How about using that creamware dsp platform to develop a clone, and then build something like the prodyssey... Just a thought!
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Post by brassteacher on Dec 3, 2010 5:24:29 GMT
How about using that creamware dsp platform to develop a clone, and then build something like the prodyssey... Just a thought! I think it would be awesome if we could just take the engine from the unreleased VSTi (I mean, that thing IS a Polymoog) and just put it into a REAL Polymoog's chasis. That way, you'd have a completely reliable, digital (but still unmistakably Analog-sounding) gig-worthy clone. Sigh, I can dream.... Do you guys think there would really be a market for something like you've both suggested? If there is, perhaps it would be easier to lobby Moog Music themselves to produce such a thing. Speaking from my experiences so far trying to set up a small company (like garage-sized at first) to build and market a high-end home audio stereo preamp, getting the beast built is actually the EASY part. Making it affordable enough for someone to be tempted enough to fork over the funds to purchase one is another matter. Skipping for a moment all the trademark and company name registration fees, and the fees for the lawyers to do that work, obtaining business licenses, etc., the expenses of getting the piece of gear you want to sell built make it difficult to produce at a sellable price point. Ironically, building the guts of the electronics itself is relatively cheap. The real expense comes from the following, in order of expense (assuming we're building a synth): 1. The power supply, 2. The controls (pots, switches, etc.) 3. Buttons and knobs (especially if you want unique custom items), 4. The chassis to house the unit. OH, if you want a keyboard, that can be either #4 or #5. Not saying a small company can't do it, but it will take VERY deep pockets to get such a thing started. And, my preamp wouldn't have to deal with licensing fees, cloning a Polymoog just might run into a few, depending on how much of the total unit you can build yourself, and what you name it, and what it looks like when done. I've stockpiles enough parts to build 10 copies of my preamp, not counting power supply, chassis, and knobs. The parts alone run about $100 per unit (only because one of the most important parts is REALLY expensive). The power supply would cost another $50 per unit, and the chassis another $200 per unit (for a small run, buying more at once would obviously be cheap per unit, but more $$ up front). So, not counting my labor (or the money and time spent to develop and build the six previous prototypes), it'll cost $350 to get one built. Now, so far, I've been lucky, and been able to demo the prototype, being able to compare it against multiple other such machines. So far, it has been noticeably better than quite a few high-end pieces made by well known companies that sell for between $2,500 and $3,000 each. And that's where I'm stuck, not enough capital up front to get the ball rolling and keep it rolling. Building a synth such as a Polymoog clone would be an order of magnitude more work and money to get going. Don't get me wrong, I'd LOVE to do it, or get together with a couple other people and work on such a project. I'd love to see it happen even if I'm not involved. However, a big company would either have build it, or a small company would have to either be formed or found to take on the project (which would require a ton of capital up front, as well as a few non-refundable-deposit preorders), or find someone like Chris or myself to custom-build each machine as an order comes in (After we build at least one just to make sure we can actually pull the project off in an acceptable manner, I mean, you'd be crazy not to ask to hear one before plunking down your hard-earned cash). The question becomes, "How much would YOU be willing to pay to get one?". Seriously, I'd like to know, since I have no idea how much money people would be willing to spend on such a thing. Also, the amount that the market would be willing to spend would determine just how such a Polymoog clone would be built. Hint: The more analog you want it, the more it will cost. Opinions on the above welcome!
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Post by chrisburrell on Dec 3, 2010 16:31:24 GMT
Interesting..
I wasn't thinking of doing it for the money because there isn't any to be had. I was more thinking about the idea that the machines could be kept going (against the odds as it were). Moog abandoned it years ago so there's no licensing issue. There's no big market for it either so really no financial gain to be had. What there is, is love.
It would appear that there is a resistance to the idea of making a smaller version using modern components.. the sort of resistance that should mean once it's failed it needs to be thrown away because it will never sound the same?
In a similar vein then, one shouldn't really play the PM through a modern amplifier / speaker system either because it wouldn't sound the same as it did through what was available at the time of its hey day. Come to that one's hearing is changing all the time so we shouldn't really listen to something twice - makes comparative listening tests a bit of a joke!
Just to make it a bit clearer, I was suggesting that if the schematic uses a CD4051 then a CD4051 would be used - just a TSSOP sized one. If the schematic says use a CD4007 (which there are lots of!) then the same applies. Transistors resistors etc all apply the same way.
When you add up the space savingness (possibly new word there) then instead of six boards you would end up with one (or two) and no wiring harness, polycom connectors and all the other mechanical things as well as saving power using modern digital equivalents where applicable.
When they restore a painting they really do try to get it as close to the original as they can. Is it better to have a restored painting or burn it - because at some point these machines will all be dead unless something is done to keep them going.
It is a bathtub curve for MTBF, and the bottom of the curve is about 20 - 30 years.
In 2110 (100 years from now) I wonder what will be in the museums from our time that still works!
Chris B
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gt
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Post by gt on Dec 3, 2010 17:50:26 GMT
Don't be despondent, Chris. I suspect it's love that makes people want to hang on to as much original as possible, 'possible' being the operative word. As it becomes more impossible then an alternative innards would be the only answer. Any luck yet with the Polycom IC info? A clone for that would be quite a coup. How are people finding the mechanics holding up- keybushes, contacts, ribbons etc? Can't put a chevvy engine in a rusty chassis (sorry about the analogy)
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Post by nervejam on Dec 3, 2010 19:15:20 GMT
Go for it, Chris. It's like in the classic car world - you wouldn't believe those guys. Any sensible person fits radial tyres and makes various 'mods' to make their cars driveable eg unleaded conversion. But no, there's always one guy who has to have it the way it came out of the showroom, and everyone else is an idiot if they don't agree with him.
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gt
Prodigy
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Post by gt on Dec 5, 2010 10:49:29 GMT
Ouch! That's a bit harsh. Isn't what you're suggesting what others are saying- do what has to be done but leave what you can? So yes, create alternatives for obsolete parts, use more resilient versions of fragile parts if poss. I'll back Chris as far as he can take this project.
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Post by spoonz on Dec 6, 2010 0:51:19 GMT
i think Chris/Nervejam you missed the vein of what i and a few other were trying to say.
We are not yet at the point where anything in a Polymoog electronically is not obtainable one way or another. Modern versions of some components at least in my experience do have an impact on the sound in a negative way. Therefore i will only change them if i have to. it's a classic just like a Lancaster bomber or a Rolls Royce car and if i owned one of them i would approach maintaining it in the same way. You change what you have to or is prudent too for the circumstance of use.
No one as far as i can see is saying they have a problem with using modern parts on any eliteist grounds and when i have to i will use modern parts just to keep the Poly going. i have stockpiled most of what i need to last me some considerable time and i suspect many other owners have or will do soon. I also see it as a challenge/fun when it goes wrong rather than a problem.
If Adrian at synthrestore who is well established couldn't get any takers for a modern divider board on what is probably a major failure point for most owners then it would indicate that many owners approach parts replacement from a similar angle. The Polycom idea is possibly a good one as they will run out at some point but a new Polymoog interior whilst a great personal achievement i think you would struggle to find many prepared to make that step. I don't think that is a Polymoog trait but one most analog synth owners would have.
If you take away what makes it what is was then why not just buy one of the existing synths that capture the sound 95% as per the original if reliability is the issue. A classic car/plane/keyboard is a classic because it is quirky,old and cranky but engaging to use. Which is why people go to such lengths to keep them that way. Sure there are people that will not change something because it then won't be the bit that the guy on the production line installed but i'm not one of them.
Incidently i have scans of many of the production notes for the Poly including things like presets that never made production and other desings for boards and revsions. Point being also i think the Polycom makeup info might be in there. If it's not the man that has the originals might help.
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Post by Polymoog Lover on Dec 6, 2010 1:37:09 GMT
What I don't understand, is why a person can't just have the parts made. I mean, after all, aren't we just talking about PCBs, ICs, stuff like that? Have them custom made the exact same way as the originals!
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Post by brassteacher on Dec 6, 2010 3:59:58 GMT
What I don't understand, is why a person can't just have the parts made. I mean, after all, aren't we just talking about PCBs, ICs, stuff like that? Have them custom made the exact same way as the originals! Everything in your suggestion is doable, except having the original transistors and IC chips remade. Fabrication processes have changed since then, and while it's possible in theory to go back and make them "the old way", not many factories are going to do that without a HUGE minimum order. Speaking of, it would take an insanely large minimum order (I would imagine in the tens to hundreds thousand) to have a factory take on the order. That is assuming they still have the tooling and photographic patterns available, and in useable condition. If they have to do all that again from scratch, yikes! This is why what Chris did to re-create the MM5823 divider chip was such a godsend (except for me, I only found out about them AFTER I parted out my almost-completely-restored-except-for-divider-chips-I-thought-I'd-never-find Polymoog ), all of a sudden there was a perfectly good, modern, more dependable replacement for a chip that may have been prohibitively expensive to impossible to have remade. Chris, I didn't mean to be discouraging, I was simply playing devil's advocate to get people to realize how involved and expensive an undertaking this can be. I've had someone turn down a $700 repair estimate for what would have amounted to almost a full restoration of a Polymoog, saying "I'm not going to spend that much money on this thing!". I have no doubt that you have the skill to pull this off, and as I said before, if you decide to try it I'd love to contribute, as I'm already working on figuring out what modern semiconductors can be used in place of the long out-of-production originals in an old Roland synth being heavily cloned these days, without altering the sound of the original synth. Also, I know you would do it just for the love of it, and believe me, I don't blame you. My wife stays on my case for not charging enough for repairs or things I rebuild to sell for the same reason! Again, the main reason for playing devil's advocate was to get some to realize that even if you built one just for the love of it, it would still be a difficult and expensive endeavor (Sorry, but spell-check annoys the hell out of me if I try to type "realise" and "endeavour"). I'm sure you have a pretty good idea how much it would cost for you to build a Polymoog clone, but I worry that the figure, either in Pounds, Euros, or Dollars would be frightening to a lot of people, even if you sold it at a point where you would just break even. A slightly off-topic but relevant comparison: Many people complain (Sometimes me as well) about the seemingly high prices some companies charge for their products. I have been an Apple/Macintosh user since, well, a LONG time #loon# , and often Apple is the target of complaints for their pricing. When the previous generation Mac Pro Tower came out, the price tag was staggering (Still is), but so were the specs (Still are). I decided to try gathering the parts and build a "Hackintosh" to the same specs while saving what I thought would be a lot of money. Well, by the time I shopped around to find TWO quad-core Xeon processors, a motherboard that would not only support dual Xeons, but have a 1GHz bus, and support a healthy amount of RAM (I never did find one that would support 32Gigs of RAM like the Apple motherboard would, and yes, I typed "32Gigs), and the same video card, I had already exceeded the price of the complete Apple machine, and had yet to get RAM, a SATA controller, a hard drive, a DVD burner, a case, and a power supply strong enough to run the whole thing. Based on my estimate of the amount of money I spent rebuilding my dear-departed PMK, which was probably close to $400 for parts alone (I sure hope Allison never reads this! ), I would guess buying all the electronic parts - semiconductors, resistors, caps, trimpots, LEDs, switches, sliders, input/output jacks, and a suitable transformer for the power supply to be somewhere between $800-$900, if you were going to build just one. You would still need to make or have circuit boards made, buy a keyboard mechanism, chassis, and hardware, including knobs and buttons. The price for the electronic components could vary depending on the amount of parts it takes to make a reasonable facsimile of a Polycom IC. Speaking of the Polycom IC, the few times I've looked at the service manual, and I probably should study more (Chris, I'm not sure wether to thank you or curse you for getting my mind going down this path the last week or so ), it appears the Polycom IC contains at least one envelope generator, a waveshaper for the sawtooth, a VCF (I bet THAT at least would be easy to figure out!) and at least one VCA. In other words, other than a VCO, it's basically a complete "synth on a chip". The more I think about it, it would HAVE to be a synth on a chip, since we all know that using "Direct Out" bypasses ALL the preset filters, but the basic sounds, Strings, Organ, Brass, etc. still come out of the synth when the preset buttons are used. Otherwise, "Direct Out" would give you a raw sawtooth or square wave that you would have to patch completely on your own from the control panels, which would mean you'd be screwed if you have a PMK . Think about it, this is also why most analog polysynths only have 6 to 8 note polyphony, there are only 6 to 8 separate VCFs, VCAs, and EGs inside, and the key assigner circuit gets to juggle which note goes through which separate voice. Geez, I've been rambling on and I still can't get my mind off this! #gone# Chris, I'm betting if there was a way to add an EG to one of these, a good start would be had on making a Polycom card: CEM3396Of course, they don't make that chip anymore either, but the concept is valid. For instance, if a small card was built using one of these: SSM2164Yes! believe it or not they still make some of the SSM chips, even though they have evolved somewhat. SSM2164 is a Quad VCA, and there is an SMT version. Now we need a Moog ladder, sans caps, built with surface mount 2N3904 transistors, and a couple of these which are only available in SMT anyway: SSM2212Those are matched NPN transistors, that should take care of the top and the bottom of the ladder. Probably need a third for the expo converter, not sure all the cards could share just one located on the "main" board. All that's needed now is an ADSR EG, or maybe two, one for the VCA and one for the VCF, not sure if the Polycom IC has two or not, I'll have to read the manual again. Then a square-to-sawtooth converter would be needed. I found a simple circuit using a 555 timer that does that, just don't know where I stored the schematic. I'm holding a Polycom card in my hand right now, and all that crap should actually fit! It'll be a bitch time-wise to do board layout, but that's just a puzzle to solve. It can even be made double-sided. The whole thing may turn out to not be as hard as I thought, but it'll still not be cheap. The SSM chips average $3.00 each, if you buy 1000. Depending on circuit board, cap and resistor costs, plus the other transistors, what do you think, about $20-$25 parts cost per card, provided enough parts to build 1000 are purchased up front? Hmm, anybody got $25,000 to loan out? or £15,997.99, or €18,873.62 at today's exchange rate? Oh, looks like you can order in quantities of 100 for about $3.40 each, so maybe $23-$28 per card. Ok, only $2,800 needed to get started. Ouch, that means a set of 71 Polycom cards would be $1,988! #jawdrop01# Oh well, it would still be easier and cheaper than hand-matching a gazzilion wee surface-mount transistors...
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Post by Polymoog Lover on Dec 6, 2010 14:51:15 GMT
I guess it all comes down to how "everything is doable, just not everything is affordable!"
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Post by vortex on Dec 7, 2010 1:02:50 GMT
Perhaps we could exploit the poor in sweatshops like the multinationals do? Small hands would be perfect for surface mounted components
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Post by chrisburrell on Feb 22, 2011 14:20:17 GMT
Just keeping up to date.
I had a very kind donation of the insides of the polycom IC and am in the position to make, er well one to start with. Of course I have the original PM to try it in so should be a synch! (Optimism is very useful).
I understand what has been said with regards making things to keep them going in as near to the original as possible - like making a polycom card - and maybe there is mileage in that as it's a simple job to replace one; compared to taking everything out and starting from scratch. The thing that bugs me the most is all those connectors.. mechanical things are usually the first to fail.
Once the polycom is out of the way as a hurdle the rest should be easy enough. Everything is more or less still available or at least there is something available that will do the job in the same way.
As to mounting surface mount parts we have an automatic pick and place machine so that's not a problem.
I rather like the idea of putting a re-vamped one next to an original to see if anyone can tell the difference without knowing which is which! (Might be a good excuse for a world challenge)
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Post by Polymoog Lover on Feb 22, 2011 16:08:59 GMT
It's good to see what a wealth of info this thread became! I was actually thinking maybe we could all chip in and make a nice document underlining the main points in this thread. That way, I can convert it into PDF and we can post in on the main page. It'd be a nice addition to the community!
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