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Producing machines that exceed the quality of old HPs is relatively trivial but will require funding. Is this community interested in investing in the development of such a machine(s)?
I'm considering a stripped down version of my OpenRPN project involving only hardware and this is my target audience. My current theory is that if you build it the apps will come. Feel free to email me with concepts outside this post. Machines such as the 35s are nice, but I'm prepared to go way over the top in terms of design. Any interest? People willing to help make this happen?
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I'd be interested. I don't know how much money I could contribute but I'm sure I could find some.
I agree that if the hardware exists, the software will likely follow. There are several good calculator software projects any of which would make a good starting place.
As for the OpenRPN project, the software development was fairly far along, so there wouldn't be a huge need to consider it hardware only :)
- Pauli
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Yes, if you build it they (the software developers) will come. The uWatch is a perfect example.
A calculator project is all about the hardware, so actual hardware = excitement. No hardware = no excitement.
No offense, but there was no OpenRPN hardware produced after how many years of development? (not even a single prototype of any aspect) How will this attempt be any different?
Also, please correct me if I'm wrong, you were somewhat adverse to producing "less than perfect" interim prototypes, which most people would consider essential for such a project. You wanted to shoot for the final product on the first attempt? Is this still the case?
Producing calculator hardware people will be happy with is far from relatively trivial.
Surely you have tons of stuff to show after all the previous OpenRPN development? If so, how about you show us some ideas so people can actually get excited and want to help out?
Dave.
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OpenRPN (& other variant projects) were failures because:
1. It solved a problem not needing much solving. Creating
decent calc FW isn't that hard these days with tons of
decent low-power microcontrollers out there, or with
iPhone, etc. platforms. Either 'Nut emulation or from-
scratch code can be done with some reasonable facility.
2. The dream software served as occupational therapy for those
folks not acknowledging it takes a ton of money & skills to
get quality case, keyboard and consumer packaging to realize
a worthwhile product one would want to use daily (as other
than a "science project" on a perfboard.) And while I
admire the uCalc (?) watch I certainly would not remove
my Rolex to wear one (same said about Casio plastic
watches). If a Calc watch were to ever be in production
it would have to have some panache/quality a la HP01 (or
even an upscaled Nat'l Semi sci calc watch from ages ago).
3. There's no need to duplicate/branch off a high-end RPL
calc (HP48, 49g, etc.) Those calcs do what they do well,
although the problems to which they're aimed often are
burdened by data entry & speed, such that PC software
is more appropriate to the task and setting.
3. I do crunch a few numbers daily and have no need for 48/49g,
etc functionality. I think others agrree - the passion is for
recovering the original elegance of the orig HP RPN calcs as
they age and drop out of circulation. Those of us doing
"powerful math" are not gonna subject ourselves to limited
calc HW when we have laptops & PCs around with Matlab etc.
There's a right tool for the job and a calculator can go
back to being a calculator and not a 'protocomputer'.
4. Original keystroke programmability was a necessary compromise
"back in the day"; later RPL programming alienated keystroke
programmers who also worked with conventional languages.
5. Bringing back a quality RPN calculator with large ENTER key
and reasonable HP layout should be goal. Programming language
should be some form of BASIC. I note the HP71B BASIC as
an excellent implementation and it could fit on an HP35S
package. For years, there's no longer any need for the
programming language to be coupled with the calculator's
direct-entry mode.
6. The HP35S is a pretty good 1st cut at recovering a traditional
RPN calculator. I don't care for the display too much and
some key layouts are 'interesting choices'. And the programming
model really doesn't make me sing.
7. Until proper case and keypad and funding work it's all a joke.
And for quality keys some agreement on key legend & shifted
key function labelling on top plate would need to be agreed
upon. If this can't be done the project can't be started
and it'll just be a buncha buttons on perfboard.
Bill Wiese
San Jose CA
Edited: 4 Oct 2009, 5:26 p.m.
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Quote:
And while I
admire the uCalc (?) watch I certainly would not remove
my Rolex to wear one (same said about Casio plastic
watches). If a Calc watch were to ever be in production
it would have to have some panache/quality a la HP01 (or
even an upscaled Nat'l Semi sci calc watch from ages ago).
I agree, and it's my baby!
The original uWatch was simply a quick exercise in what could be done with off-the-shelf parts, so that's what it looked and felt like. It was actually done for a design contest (I didn't even place :-( )
The new uWatch Mk2 design is evolving slowly, so it should hopefully answer the criticisms of the first one. Namely:
1) A "real" case made out of anodised aluminium, so it should "feel" like a solid quality watch. Real integral watch band pin supports etc.
2) A graphical LCD display with a nice backlight.
3) Bigger more powerful processor. The programming community maxed the old one to death playing chess and all sorts of things!
4) Bigger spaced keys. In fact this one will use touch technology. The major problem is deciding exactly how to implement this. I originally crammed 24 buttons on the thing, even though I knew it probably would be unworkable in practice unless you have the worlds smallest fingers. My current thinking is to just go minimalist so the touch technology will actually work nicely for all. 16 or 18 keys max. Who cares if you have to hit shift for nearly everything, worked fine on my CFX-400 sci calc watch.
Don't like the key layout? Design your own PCB front panel.
5) USB and rechargable battery.
If I get off my butt and actually lay some money down to get the first prototype, it could be a decent product (I hope)...
Dave.
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Quote: DaveJ wrote:
I agree, and it's my baby!
The new uWatch Mk2 design is evolving slowly, so it should hopefully answer the criticisms of the first one. Namely:
1) A "real" case made out of anodised aluminium, so it should "feel" like a solid quality watch. Real integral watch band pin supports etc.
Sorry, Dave, a 'real' watch does not have an alum. case.
Good watches (which excludes most all Seiko, Citizen, Skagen, Pulsar, Casio, Swatch, etc) have at least 316 stainlees for case, and they also have (near-)scrtachproof sapphire crystals.
If you're gonna produce something attempting to be sellable, don't fight for the low-end. No margin for time & effort. Sell 'em for $500 - $1K, not $125 or less. Also, higher-end watch cases and bands are avaiable for custom watch builders from sources like [url]http://www.ofrei.com[/url]
Quote:
1) A graphical LCD display with a nice backlight.
Please, don't overdo graphics. While graphix LCD might be required to do better-than-character-LCDs don't do graphics per se on the calc. Get RPN + memory/transcendentals and maybe some 12C PV/FV/PMT/i/n running and you're done.
Think something like Tritium capsule or other watch illumation like Indiglo.
For small volume production rape Timex or Casio calc watches.
Quote: 3) Bigger more powerful processor. The programming community maxed the old one to death playing chess and all sorts of things!
Please O Please No! A low power 80c51 etc is fine - or even better a watch CPU. Find the BEST lowest-power CPU you can. Don't build a "computer". Battery life needs to be 1-2 years just like Casio calc watches.
Given touch sense (below) a Cypress or Atmel is likely best sol'n.
Quote:
4) Bigger spaced keys. In fact this one will use touch technology. The major problem is deciding exactly how to implement this. I originally crammed 24 buttons on the thing, even though I knew it probably would be unworkable in practice unless you have the worlds smallest fingers. My current thinking is to just go minimalist so the touch technology will actually work nicely for all. 16 or 18 keys max. Who cares if you have to hit shift for nearly everything, worked fine on my CFX-400 sci calc watch.
I agree. I also had the CFX20 wathc and CFX400. Capsense touch is the way to go and can work thru a watch crystal. A side button and timeout reversion should shift in/out of calc mode so capsense disabled and not burning power etc. Do not try use big LCD legends
for keypad, use printed logo. Capsense touch processing can solve 'fat finger' issue and can even do stroke recognition.
Quote:
5) USB and rechargable battery.
Nobody wants a friggin' watch that has to recharge.
1+ yr battery life, or stay home.
If a stylish, $1000 stainless+sapphire QUALITY {too many nerds here who think Seiko=quality) watch that has an RPN calc with 1+ yr battery life hits the market, enough folks will buy, and money is made to recoup costs.
Frankly, Plan B is to work with Casio on a custom run to reprogram one of their touch calc watch variants and have it dropped in a quality case + sapphire face w/quality band.
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Quote:
Sorry, Dave, a 'real' watch does not have an alum. case. Good watches (which excludes most all Seiko, Citizen, Skagen, Pulsar, Casio, Swatch, etc) have at least 316 stainlees for case, and they also have (near-)scrtachproof sapphire crystals.
If you're gonna produce something attempting to be sellable, don't fight for the low-end. No margin for time & effort. Sell 'em for $500 - $1K, not $125 or less. Also, higher-end watch cases and bands are avaiable for custom watch builders from sources like [url]http://www.ofrei.com[/url]
Yes, I really meant aluminium as a minimum, not plastic. Stainless is a more expensive option, just gotta specify it. Easy.
Sapphire crystal is another expensive custom option. Anyone know where you can get such things custom machined?
I'm realistic enough to know that I perhaps don't quite have the skills on my own to design a watch worthy of a $1000 price tag.
At that sort of price people expect fancy presentation cases, a really elegant case design, 5 year warranties etc. This tends to push the risk aspect (financial and time) into the stratosphere.
The uWatch was butt ugly, but it made a lot of people very happy. I can't begin to imagine what impact a slightly more refined version would have, one that looks like you could actually wear it every day. And I can do that with very little financial outlay or risk.
I know enough about various industries to know that price-point is an important factor. It can make or break your product.
Quote:
Please, don't overdo graphics. While graphix LCD might be required to do better-than-character-LCDs don't do graphics per se on the calc. Get RPN + memory/transcendentals and maybe some 12C PV/FV/PMT/i/n running and you're done.
Think something like Tritium capsule or other watch illumation like Indiglo.
For small volume production rape Timex or Casio calc watches.
I haven't overdone graphics. I've pretty much settled on a 128x32 display, much to the disdain of the community who wanted a 128x64
Backlight is integral white LED and is very nice. Not the lowest power solution, but backlights are not used often, and it's integral, so no development effort or risk.
Raping parts from other products is fraught with danger. If I sold a couple of hundred uWatch's, then I'd be crazy to think in design terms for anything less than 1000 Mk2's.
Quote:
Please O Please No! A low power 80c51 etc is fine - or even better a watch CPU. Find the BEST lowest-power CPU you can. Don't build a "computer". Battery life needs to be 1-2 years just like Casio calc watches.
Given touch sense (below) a Cypress or Atmel is likely best sol'n.
I've speced in an Atmel touch device.
A low power micro is fine, but remember the other stuff takes power too, so it ain't just about the micro.
The uWatch used a 64KB/8K 16 bit processor, and we ran into the limitations very quickly. No one is going to want to have to code in assembler...
You can have your cake and eat it too here. A big processor can be clocked at 32KHz or shut down and draw adequately little power in time/date mode, but then has the grunt when and if you decide to use it. One can also argue a 32 bit processor is actually more efficient power-wise than an optimised low power 8 bit micro. There ain't much in it.
Quote:
I agree. I also had the CFX20 wathc and CFX400. Capsense touch is the way to go and can work thru a watch crystal. A side button and timeout reversion should shift in/out of calc mode so capsense disabled and not burning power etc. Do not try use big LCD legends
for keypad, use printed logo. Capsense touch processing can solve 'fat finger' issue and can even do stroke recognition.
Actually, no. Cap sense creates the "big finger" problem. You can get higher density using tact keys because the finger can "feel" before pushing. Cap sense has to be spaced big enough to absolutely ensure it can be used by anyone. Although admittedly I have not experimented in this area yet, mainly going by what the informed are telling me. You think say reliable 6mm pitch keys with touch sense is possible? I'd love to see some foolproof implementation examples, please.
Quote:
Nobody wants a friggin' watch that has to recharge. 1+ yr battery life, or stay home.
If a stylish, $1000 stainless+sapphire QUALITY {too many nerds here who think Seiko=quality) watch that has an RPN calc with 1+ yr battery life hits the market, enough folks will buy, and money is made to recoup costs.
Frankly, Plan B is to work with Casio on a custom run to reprogram one of their touch calc watch variants and have it dropped in a quality case + sapphire face w/quality band.
Unfortunately I'm being forced down the rechargable path.
The display takes around 100uA continuous, so even if I had a decent 500mAh capacity coin cell that's only around 200 days. And I have not factored in a DC-DC, touch sense, processor, occasional backlight use etc. Then the case design is more complex because you have to allow easy battery access. Yes, it can be done, but it means a custom LCD display and the entire project explodes into complexity from there. Complex development means more money, more time, more risk, and will ultimately never get done because I'll lose the enthusiasm. BTW, I'm already looking at around 1 month battery life for the rechargable.
Find me a suitable lower power LCD solution off-the-shelf and I'll happily consider giving you a year battery life. Really.
People who have not actually done in-depth investigation into designs like this can't really appreciate the countless trade-offs involved. I don't think I could even begin to list all the trade-offs I've encountered in this project. Not as many for pocket calc to be sure, but still, many gut-wrenching decisions need to be made. And I've said this before, this never works well by-committee or by-community. It need one smart person to do the legwork and make the big decisions for such a project.
That's why Hugh needs to simply make decisions, do the work and SHOW us something tangible. Then people will get excited and want to help out. It's a real shame nothing but software has come out of OpenRPN.
I believe OpenRPN never got off the ground because perfection was aimed for. I like being a tad more realistic with my projects. Perfection and gilding the lily is nice, but not needed for a successful product.
Dave.
Edited: 4 Oct 2009, 10:32 p.m.
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Dave, please do what you are going to do the way you want to do it.
If it costs $1,000, I will buy exactly zero. My propensity to drop substantial money on toys maxes out well below that figure.
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Quote:
Dave, please do what you are going to do the way you want to do it.
I always do! :->
I have 20+ years experience doing projects and kits like this for niche markets so I like to think I have at least some sense for it after all that time!
Quote:
If it costs $1,000, I will buy exactly zero. My propensity to drop substantial money on toys maxes out well below that figure.
So does mine.
You won't see me ever produce a $1000 niche hobby product, I know it would be a guaranteed loser.
The "magic figure" in the consumer market is $300, and the niche hobby market is substantially less than that.
Dave.
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Quote:
7. Until proper case and keypad and funding work it's all a joke.
And for quality keys some agreement on key legend & shifted
key function labelling on top plate would need to be agreed
upon.
That will never work, you'll never ever get even close to majority agreement on such things. I think any design should be minimalist and have support for a drop-in face plate. This would not lock you into such critical design decisions at the start of the project.
You could also argue that you could do that with the hardware too. Use an FPGA perhaps so you can change the processor to anything you like.
I agree with what you say about big powerful calcs, I simply don't see the point. There are already plenty of calcs out there that fill this market. Think SMALL and really pocketable.
Aluminimum case to set the thing apart from a million other calcs on the market. because no matter how much money and effort you pour into the case and key design, it's still doomed to look like every other plastic chinese calc out there. Think different. Think about people who might want one (Geeks, Hackers, Makers, Steampunkers) simply because it looks cool.
Dave.
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Quote:
That will never work, you'll never ever get even close to majority agreement on such things. I think any design should be minimalist and have support for a drop-in face plate. This would not lock you into such critical design decisions at the start of the project.
Screw the majority. Just do it right. Have an opinion that's based on ease of use/minimizing keystrokes.
You're either building a product or a science project.
Quote:
You could also argue that you could do that with the hardware too. Use an FPGA perhaps so you can change the processor to anything you like.
Baloney. Any reasonable calc for a watch can be done on a 4 bit CPU or even a bit-serial CPU.
FPGAs are not really designed for ultraportable ultralowpower and have lotsa pin/package baggage.
Quote: Aluminimum case to set the thing apart from a million other calcs on the market. because no matter how much money and effort you pour into the case and key design, it's still doomed to look like every other plastic chinese calc out there. Think different. Think about people who might want one (Geeks, Hackers, Makers, Steampunkers) simply because it looks cool.
For a hand *calculator* and not a *watch*, yes.
And laser-etched keytops and plates can be done in smaller-volume,
with colored plastic filler filling in the keytop legends.
[/quote]
[/pre]
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Quote:
Screw the majority. Just do it right. Have an opinion that's based on ease of use/minimizing keystrokes.
You're either building a product or a science project.
The HP 41 had a template overlay, and it was a good product, so I think it's doable if you want to.
Quote:
Baloney. Any reasonable calc for a watch can be done on a 4 bit CPU or even a bit-serial CPU.
FPGAs are not really designed for ultraportable ultralowpower and have lotsa pin/package baggage.
Sorry, I'm not talking about the uWatch here, I'm talking Hugh's proposal.
Yes, FPGA's chew power and mostly big pin counts. But it could be novel for an open source powerful calc if you wanted to go that way.
I prefer hard silicon micros for stuff like this, but I like to be open minded too. (I design FPGA development tools for a living)
Dave.
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Quote:
but will require funding
You will need at least $4m and there is a 99.9% chance you won't get this money back. But don't take my word for it - go and find a venture capitalist for a second opinion.
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Quote:
You will need at least $4m and there is a 99.9% chance you won't get this money back. But don't take my word for it - go and find a venture capitalist for a second opinion.
You are generous with those odds at $4M!
Try $4K as an order of magnitude for a DIYer, $40K if you want it really schmick. Heck, give me a lousy $400K and I'll quit my job and go full time at it :->
I (and many others I'm sure) could quite easily produce a very usable calc for under $10K, provided I had help with the mechanical CAD stuff.
Even if I spent that sort of money on my MK2 uWatch (it won't even be close to that), it's practically a 100% certainty I'll get my money back on that investment. I think there is little risk in any sub $10K design that is done well. Over that and your odds start dropping fairly quickly I recon. I base that on a typical price-point and sales numbers of a project like my uWatch.
But like I've said in the past, I don't quite see the point in doing yet another pocket scientific calculator design. There are just too many other platforms out there. It would have to have some niche appeal that is not currently being met. e.g. a REALLY pocket size calc (no the Voyager is not what I call pocket size) and/or some really funky all-metal design etc. Perhaps a retro LED calc even. Heck you'd probably sell a few hundred of those small non-programmable 4-banger type RPN designs doing the rounds a while back. Get it on ThinkGeek and you'll probably quadruple that number.
Dave.
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Quote:
You are generous with those odds at $4M!
Try $4K as an order of magnitude for a DIYer, $40K if you want it really schmick. Heck, give me a lousy $400K and I'll quit my job and go full time at it :->
I (and many others I'm sure) could quite easily produce a very usable calc for under $10K, provided I had help with the mechanical CAD stuff.
If you look at the original post you will see
Quote:
Producing machines that exceed the quality of old HPs is relatively trivial but will require funding
This is not a "usable calc" but one which exceeds the rather excellent standards of the old HPs. That cannot be done cheaply nor can it be done at any of the prices you are proposing.
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Quote:
This is not a "usable calc" but one which exceeds the rather excellent standards of the old HPs. That cannot be done cheaply nor can it be done at any of the prices you are proposing.
If you seriously think a skilled person cannot product an excellent quality product for a niche market for the figures I quoted then I'd guess you have a no experience at all in designing electronics products "mightnight engineer" style.
Remember several things:
No one is talking about starting up a company here, and it does not require more than a couple of experienced individuals to produce a world class product. You can even do it with one person if they have all the required skills.
And if you read Hugh's original post also:
Quote:
and this is my target audience
So it hardly has to a perfect gold plated world class product in a fancy silk lined box with a nice hydraulic closing lid.
Labor is FREE. This is a community/hobby project, people will not charge for their time.
There are no overheads or other expenses apart from prototype manufacturing costs.
There is nothing magical about the standard and quality of the old HP's, sorry to burst your bubble. In fact some of them were not all that great.
It's not rocket science to design a quality robust product like this. The electronics is trivial, don't even mention it. The case is not hard - make it metal and it will be more robust than anything HP has ever produced - ever. Chose a high quality brand LCD and it and the LED backlight will last as long as you want.
So what's left?
The only issue I see is with the quality/reliability of the keys, and this is not rocket science either. Top quality tact domes like Snaptron for example have rated lives of 5,000,000 actuation's. I've got a hole box of them on my desk, and they cost me nothing.
Couple that with top quality gold plating on your board and a nicely designed keytop, mount and legend system and you are done. It'll take a few prototypes to iron out the issues and get the "feel" right, but it's far from hard. All it takes is for someone to DO IT.
Heck, even if I or others had to HIRE a professional contractor to design the case and keys, the project would still come in well under the $40K I mentioned, let alone the $400K I mentioned to do it as a full time job, or the silly blue-sky figure of $4M you mentioned.
Dave.
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I'm with DaveJ on this, $4m is way too high an estimate unless you're into burning money needlessly in startups.
- Pauli
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Quote: I'm with DaveJ on this, $4m is way too high an estimate unless you're into burning money needlessly in startups
or it was a government operation.
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I suppose there are experts here. So, how much is it really for a rapid prototyping of Hugh's CAD drawings (case and keys), the PCB and a LCD?
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Quote:
I suppose there are experts here. So, how much is it really for a rapid prototyping of Hugh's CAD drawings (case and keys), the PCB and a LCD?
The PCB will be around the $100-$150 mark + components.
The rapid prototyped case will depend on who does it. But emachineshop will do my fully custom uWatch2 case for around $200-$250 mark for 5 or 10 or so. Their prices are based on type and amount of material used + amount of machining. So figure maybe $500-$600 for the case + blank keys? (+ legend?) I believe there are people on this group with access to such machines as well. You have to use the emachineshop software though, but the advantage is you know exactly what it's going to cost up-front.
For the LCD you'd be crazy to go custom for such a project, plenty of suitable off-the-shelf solutions from the likes of Newhaven and CrystalFonz. A suitable LCD with nice backlight might be $20-$30
Dave.
Edited: 5 Oct 2009, 9:38 p.m.
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I just got 100 multilayer (4-layer) SMT PC boards made, slightly smaller than what we'd need for a calculator, for about $800, including the NRE (non-recurring engineering) and all setup charges and bare-board automated testing.
At the last place I worked, we looked into getting a keyboard made with double-shot keys, and as I remember, the tool-up was something like $2-3K. That was 20 years ago, but I think that would be greatest part of the cost. We've had lexan overlays made like the HP-41 has around the keys, and, although we didn't have to get the die made to make all cutouts for the keys, the NRE was under $2K.
We also looked into getting a custom LCD made for a product, and that was a couple grand too. We ended up using an off-the-shelf one for about $6/ea.
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Quote:
I just got 100 multilayer (4-layer) SMT PC boards made, slightly smaller than what we'd need for a calculator, for about $800, including the NRE (non-recurring engineering) and all setup charges and bare-board automated testing.
Yep, that's pretty standard these days. Who did you use? I use www.pcbcart.com
Quote:
At the last place I worked, we looked into getting a keyboard made with double-shot keys, and as I remember, the tool-up was something like $2-3K. That was 20 years ago, but I think that would be greatest part of the cost. We've had lexan overlays made like the HP-41 has around the keys, and, although we didn't have to get the die made to make all cutouts for the keys, the NRE was under $2K.
Yep, keys are the only major cost in the whole exercise really. You'd just have to budget for a few spins to get the physical interface right.
Dave.
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Quote: Yep, that's pretty standard these days. Who[m] did you use? I use www.pcbcart.com
Imagineering (pcbnet.com) .006" trace/space, .015" vias. Another one of the several boards for the project was .030" thick, with .008" vias.
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I conclude that Hugh could have a prototype for about $1000, something to show and to study if it mechanically works. With some luck, it would already demonstrate a viable design. Considering time and effort that have been invested, I can't understand why there is still no prototype.
Edited: 6 Oct 2009, 5:16 a.m.
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