On 6/21/10 2:45 PM, Ethan Dicks wrote: Seconded. I'm much more interested in a bare board, perhaps along with any hard-to-find chips. -Dave -- Dave McGuire Port Charlotte, FL

On Mon, 21 Jun 2010, Ethan Dicks wrote: Well, download the P112 manual and check the SRAM, boot ROM, and surface mount parts off. Those chips and the board would be what you'd get in the partial kit. I'd probably add seral pigtails too because I got a metric buttload that I won't be able to get rid of otherwise. -- David Griffith dgriffi at cs.csubak.edu A: Because it fouls the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail?

On Mon, 21 Jun 2010, A. Christoff Baumann wrote: Right. I'm trying to get people to use my new(ish) domain. 661.org. See http://661.org/p112 -- David Griffith dgriffi at cs.csubak.edu A: Because it fouls the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail?

On Jun 21, 2010, at 12:16 PM, Tony Duell wrote: Why would you want to go through the pain of stuffing your own SMD parts? Note that it wouldn't necessarily make the kit any cheaper. The cost of stuffing the SMD parts was negligible compared to the total cost of the kit. It is also my understanding that the CPU and FDC are both completely unavailable in anything but PLCC packages.

On Jun 21, 2010, at 12:29 PM, David Griffith wrote: Oh, yeah, sorry. Been a long night. It should be noted that the original design ideals, and for that matter what makes the P112 cool for a lot of people, is the design as it sits. It's a very easy to build kit, requiring only the assembly of discretes and a couple of IC sockets. I've built P112's in an evening. If you want a more "traditional", retro-appropriate design, check out N8VEM. He's built a pretty awesome through-hole system that uses individual boards for things like the controller, disk I/O, etc. Heck, there's even ways to make it S-100 if that tickles your fancy. P112 was (I believe) designed to be mounted to a 3 1/2" floppy drive and provide a functional full-featured CP/M computer by itself with said floppy drive and a serial terminal. It's not the be-all end-all of CP/M SBC designs.. in fact, it sometimes leaves a lot to be desired from a true hard-core CP/M-ists stance. However, as an introduction to SBCs, and as a retrocomputing project, the P112 is exactly what it purports to be.

On Jun 21, 2010, at 12:32 PM, Dennis Boone wrote: Because many people have difficulty soldering SMD parts, and we can have a professional robot pick-and-place the parts at a cost that is negligible for us compared to supporting people who will invariably screw that step up. Additionally, being the static-sensitive nature of the parts and their small size, it makes inventory easier for us. And for myself, my eyesight is such that I can't even see well enough (at age 40) to solder SMD anymore on a tight board. In the last production run, we had one or two defects, and that was difficult for me to fix: I can't imagine having to solder all the pins and doing it successfully. Dave: I have a small number of unstuffed boards as overages from the last production run. If people really want to do all the SMD stuff, order a few extra parts and we can package up the unstuffed boards to people who like eyestrain and/or have their own wave-soldering systems.

On Jun 21, 2010, at 1:51 PM, Dave McGuire wrote: I've had the right tools. I don't buy cheap RadioShack soldering irons. I have a very nice digital temperature controlled Weller soldering station with the right tips. I can do it, I just don't like to, and I have a high enough failure rate to make it an exercise in frustration when dealing with large-pin count flat-packs. It does require different skills than through-hole soldering. Not everybody is up to the task. I build on average two-three kits a year: at that pace, SMD just isn't a skill I get enough practice using. I can probably dress and lace telephone and datacom cable faster than you can, I'd wager.. but I wouldn't expect your home network to have all the cables dressed and laced, either, because you probably have never laced cable in your life (I'm assuming you don't work in the telecom sector like I do). Different people have different skills and abilities. Also, not everybody wants to invest in $300 worth of soldering equipment to build a $120 kit. For some people it is just a hobby, they don't need (nor can they justify) spending a lot of money on tools. I agree that the "right tool makes all the difference" in general, but I'm not going to ask the average electronics novice to spend more than the kit is worth on expensive tools they don't really need for anything other than my kit. The whole point here is to create an accessible, entry-level kit... if people have SMD skills and equipment, more power to them. SMD components were designed to be picked-and-placed by robots. By that measure, the "right tool" for the job is an industrial robot designed to pick-and-place SMD parts. I don't have a problem with letting a robot do the hard stuff I can't quite do with 99.999% accuracy. If you can, great. Please enjoy building kits that challenge your skills. That's not what P112 is.

And I am convinced that most of those who claim that SMD work is difficult are those who have never tried it becuase they know it's difficult. My guessis that if they actually grabbed a suitable iron and had a go they;d find it remarkably simple. -tony

I feel the same way about through-hole (or tagstrip, or ....) soldering. People keep on telling me that soldering is hard. I actually wonder if they've tried and practiced with a soldering iron, or if they were just told it's hard and believe it. On the other hand, I know that if you find a skill easy, it's difficult for you to think that anyone will find it difficult. WHich is incorrect, of course. There are plenty of things that I find impossible that others find trivial. To tie into another thread, one of the photos of the VCF-UK that I saw (I can't rememeber who took said picture) seemed to be of Spectrum (?) ULA built from simple logic chips on large plugblock breadboard. While that's undoubtedly a great hack, I do have to wonder why the chap didn't solder it up on stripboard or similar. Anyone who has the dedication and knowledge to make a copy of the ULA is capable of learning to solder. And the resuylt would be a lot more permanent and probably more reliable. -tony

Wire-wrapping id fine, and very reliable. It's also pretty stable. Those solderless plugblock breadboards are none of the above :-) I am quite sure he needed to test and modify the design as he went along, and maybe it;s easier to do that on a solderless breadboard (I doubt it, actually, I had so many problems from bad connections on those darn things)... But it's not had to 'edit' a design on stripboard. So perhaps transfer each bit to stripboard as you get it finalised? Cerrtainly if I'd managd to make a clone of a ULA in such a machine I would not have kept it on a solderless breadboard, even if I'd used one to develop the reverse-engineered design. -tony

So? IUt's actually not much harder to tweak thigns on stripboard, and you know your problems are due to errors in the logic rather than bad connections, wired that have dropped out, or excessive stray capacitance (all of which caught me when I was silly enough to use solderless breadboards). Pity... Big boards to TTL are a lot more fun :-) Indeed... -tony

On Jun 21, 2010, at 12:47 PM, Tony Duell wrote: It is worth noting that Dave and I's experience is that the people who want the P112 kits typically don't want to diddle with SMD components. Not everybody is comfortable with SMD parts (I'm not, and I've been building kits for 30 years), and the P112 was designed to be a painless introduction to kit computers. Many of our customers had built the P112 as their first kit, or at least their first kit since the days RadioShack sold.. radios. P112 is a great introduction to retrocomputing at a low cost of entry (both financial and in assembly skill). That's it's strength, not it's weakness. Speaking for myself, I don't think Dave should change that.

On 6/21/10 4:49 PM, Keith M wrote: Oh good heavens. This sort of stuff really just sounds like nothing more than knee-jerk automatic hatred of SMT by people who did what I described in my last message, and it really does become irritating to those of us who know better. Right now I'm sitting here (well, taking a break from it at the moment, actually) soldering sixteen boards with 0.5mm-pitch parts for another open-hardware project, and am having no trouble whatsoever. I find it quite enjoyable and completely trouble-free, and I'm by no means the smartest, best-coordinated, or best-sighted person here. The equipment isn't particularly expensive (despite popular underinformed opinion), and the skills take an afternoon to develop. If you were to actually TRY it, with the right tools, and the right mindset (as in "learning a new skill" rather than trying to treat it like it's through-hole soldering without the holes), I bet you'd love it. -Dave -- Dave McGuire Port Charlotte, FL

On 6/21/10 5:05 PM, Fred Cisin wrote: That's an excellent idea. Several companies (Spark Fun comes to mind) sell "practice" boards. -Dave -- Dave McGuire Port Charlotte, FL

What would Heathkit do? -- Will

On Jun 21, 2010, at 2:27 PM, William Donzelli wrote: Close their retail stores and essentially be a reseller of educational kits before fading into absolute irrelevancy.

On Jun 21, 2010, at 2:44 PM, William Donzelli wrote: Heathkit disappeared largely because electronics (and ham radio as well) as a hobby has drifted out of the mainstream and into a pretty selective niche. Electronics parts stores in general are largely an anachronism... even RadioShack has been desperately trying to shake off the "back wall" and become a cell phone boutique store. I think the reasons for this are quite complex. First off, there's the (IMHO) utter failure of the educational establishment to instill in youth a desire to tinker and experiment. This isn't a new thing: even when I was a teenager this was strongly discouraged, however the stakes seem to be a lot higher with everybody "jumpy" about "security" and the like. It is also worth noting that at my high school I was the last class to have an "electronics shop" class available at the high-school level. Secondly, as a society we've become very jaded about tech. Every six months there's some new "revolution". Think about just the past five years in the cellular business, for example, to see this in action. Android. iPhone. Blackberry going from an executive toy to a consumer platform. 3G widely deployed, and now 4G being implemented in most major markets. Integration of websites like Facebook and Twitter into the handset experience (see: Android). Cameras and GPS in every phone. Cellular data services being implemented in consumer electronics (Kindle/nook, iPad and netbooks). Each one of these in and of itself is quite a game-changer, and all of these converging has turned the cell phone from "just a phone" into a nexus of communication and interaction. A crystal set radio seems... out of place in a world where broadcasting consists of a finely tuned stream of podcasts and music tailored to your exact listening preferences. And how long until MW AM transmissions cease and a crystal set no longer even "works?" It is this latter issue that really rears its ugly head. Many of the "first project" kits involving electronics are increasingly irrelevant. Perhaps not to the skill of teaching electronics, but as a "useful tool once built." Some of the best first projects in electronics were fun because they created toys that could immediately be enjoyed. When I was 9, the two high-power AM stations in the Los Angeles area still played Top-40 music (that would be KFI and the border blaster XETRA, then called "The Mighty 690") and would drive a crystal set with 15 feet of wire. The big thrill was listening to the stations I enjoyed already on something I built out of a couple of electronics parts purchased with my allowance. What does a kid building a crystal set have to look forward to listening to nowadays? Rush Limbaugh? Ranchero music? If they're lucky and have an interest in sports, maybe a baseball game (once I learned some basic antenna theory, I could pick up both Angels and Dodgers broadcasts on my crystal set). But I tried getting a nephew this age interested in electronics this way, and it was a challenge. They just didn't see the mystery of pulling a signal out of the air with a few parts and no battery. A crystal set just isn't magic to a tweener who already has a cell phone with Pandora, YouTube videos, and MySpace at their fingertips. Many of my early forays into electronics involved building something I didn't have and wanted, and kids today pretty much have everything. As does society. I don't know what the solution is. But Heathkit's demise may in some small way have to do with the fact that electronics is so cheap and ubiquitous in our society that it no longer has any magic. It's sad, but in the march forever forward, where electronics are becoming increasingly complex and the skills required to build anything of relevance increases (while the discrete components disappear into assembled IC subsystems) it may be inevitable that the barrier for entry becomes pretty high. If you figure out a solution, there's an entire hobby (amateur radio) that is dying that would love to hear your solutions.

On Tue, 2010-06-22 at 09:59 -0400, Teo Zenios wrote: Well, maybe in some instances, but NewEgg is pretty good...and it is certainly easier to build machines from parts now than it used to be. That said, it sometimes is worth it just to pay a little extra to not have to futz with getting things 'right'

This. However, I don't bother coding for newer stuff either because there's no permanence to it. Certainly with Mac OS X, the landscape changes regularly and yesterday's star API is tomorrow's deprecated dogfood (see Carbon). If I write classic Mac software, it runs on any classic Mac. If I write Commodore 64 software, it runs on any Commodore 64 and a good deal of emulators. So screw Snow Leopard. Computers and software are commodities. The old days of special systems and maintaining them are gone. Today, they are interchangeable and, with few exceptions, everything looks like everything else. -- ------------------------------------ personal: http://www.cameronkaiser.com/ -- Cameron Kaiser * Floodgap Systems * www.floodgap.com * ckaiser at floodgap.com -- The Devil can cite Scripture for his purpose. -- Shakespeare ---------------

On 6/22/10 9:43 AM, A. Christoff Baumann wrote: selective niche. and become This has been discussed here several times recently. You're fifteen years too late with this complaint; Radio Shack's parts offerings did hit rock bottom years ago, but they have gone back up considerably in most places over the past five years. They even started selling microcontroller stuff (Parallax) a few years ago. Part of the problem is that the parts areas LOOK smaller now due to having evolved from horribly inefficient pegboards to those large metal drawers for holding their parts stocks. Less square footage, more components...just less visible. Electronic components don't need to be "shown off" in well-lit glass display cases, while cell phones do. desire to Yes, it's sheer insanity. Just watch the average soccer mom's eyes open wide when they hear the evil, scary word "DEVICE". "Oh my god, a DEVICE!!!" ...it seems to be implied that it means something bad. And heaven help you if you use that word within five miles of an airport. Any time one of these morons sees a piece of wire, they panic. No, the situation is nowhere near as dire as this, actually it's quite bright. If this were ten years ago, I'd agree with you, pour you a beer, and shed a tear, but it has all come back...and with a vengeance! Read on. Electronic components vendors: In 1975, we (the USA) had Radio Shack and Lafayette, and maybe a few little regional chains. Now they number in the thousands, and their business is booming. Electronic kits: There are more electronic kit vendors than ever before. Yes, the loss of Heathkit sucks, I grew up with that company and their products. But look at what we've got now! There are so many I can't even begin to name them...Hundreds of them, and they're growing like weeds! One of my favorites, Spark Fun Electronics (not strictly a kit company, but close) has experienced near-exponential growth recently and had to move into a much larger building. Places to do stuff: "Hacker spaces" and "maker spaces" are popping up all over the country, even here in the technological black hole that is Florida there are several. I visited a VERY impressive one in Atlanta a few months ago while on a road trip. Ten thousand square feet of pure geeky joy. People etching PCBs, building robots, fixing things, writing code, experimenting on solderless breadboards, restoring a Tektronix 500-series oscilloscope...I showed up there at 2AM (I was on a road trip) and there were four people there working on projects! "Maker" gatherings: These things get HUGE attendance, with people building and showing off robots, homebrew computers, gadgets of every kind, soldering classes (ahem!), etc etc etc. Sure, nobody is messing with crystal sets like you and I did. They were fun in our childhood days, but they aren't today, as you pointed out. But what we've gained far, far outstrips what we've lost, IMO. Today, there are teenagers building powered model airplanes with GPS receivers, microcontrollers, and servos that take a programmed set of coordinates, take off, and fly there. This is good stuff, and most of it is being done by young(er) people. ...unless of course this is just a crotchety-old-man-fest, at which point I'll shut up and go about my business, and tell you to "get off my lawn!" ;) (your mailer is sending out paragraphs as one very long line, by the way) -Dave -- Dave McGuire Port Charlotte, FL

On 6/22/10 1:21 PM, A. Christoff Baumann wrote: I will reply to the rest of your message later, I have to run out now, but this part...Argh! I will have to look into this when I get back. I was unaware of RFC3676, thank you for the pointer! -Dave -- Dave McGuire Port Charlotte, FL

Was RFC 3676 pushed through by MICROS~1's equating of an email message with a WEIRD document? RFC 3676 is less than ten years old (Feb 2004?). Should this list conform to RFC 2646 (1999?), instead? On Tue, 22 Jun 2010, Cameron Kaiser wrote: . . . but if it is more than 72, then the FORTRAN card sequential numbering doesn't have space. I remember several EAM machines that were configured (plug-board) to ignore anything past 72 ALSO, since people often don't trim the replies to the replies to the replies, it's nice to leave some room for when the chevrons get inserted. "Soft line breaks" are fine for text that will be reformatted in an editor, etc. But they are a nuisance when they get quoted. -- Grumpy Ol' Fred cisin at xenosoft.com

In article <8E7A0F47-FEFD-4BFA-A834-9D8BDCF224DD at feedle.net>, "A. Christoff Baumann" <feedle at feedle.net> writes: If I am reading RFC 3676 correctly (and I've only read it for the first time today, so perhaps not), there are problems with the message you've given at the above URL: 1. The Format=Flowed parameter isn't given in the Content-Type header as described in section 4. If Format=Flowed isn't present, the mailer is to assume Format=Fixed. This message appears to be half-compliant with the RFC. Its unknown to me if its the user's MUA that is the problem or the mailing list software. 2. Quoted-printable is used against the SHOULD recommendation in 4.2. -- "The Direct3D Graphics Pipeline" -- DirectX 9 draft available for download <http://legalizeadulthood.wordpress.com/the-direct3d-graphics-pipeline/> Legalize Adulthood! <http://legalizeadulthood.wordpress.com>

On 6/22/10 3:22 PM, William Donzelli wrote: [cue Twilight Zone music once again] Are you even looking at where these sellers actually are today, which is online? I wasn't alive in the 50s or 60s, but I can tell you that what I saw in the 70s was NOTHING compared to what we've got now. The only advantage back then is I could ride my bike up the road and buy parts at Radio Shack, while now I have to wait 2-3 days for stuff to arrive via FedEx or UPS. There are hundreds of component suppliers, and dozens of kit vendors. Are you seriously asserting that there were more than that in the 1950s or 1960s? -Dave -- Dave McGuire Port Charlotte, FL

Serious question : Apart from the obvious one [1], was there any Heathkit that required SMD assembly? I seem to remember that some later Heathkits were nto really kits at all, with very little soldering to do :-( I am not sure if any Velleman kits involve SMD assmbly, certainlty the ones I've built have been all through-hole. I seem to remember at least one Maplin kit (back when Maplin made and sold their own range of kits) that had some SMD parts, though. [1] Heathkit prodcued an education kit to teach SMD soldering. You ended up making a flashing light or something uisng SMD components. Needless to say that one did come with an unpolulated PCB -tony

On 22 Jun 2010 at 16:13, Ethan Dicks wrote: Since I'm considerably past that, I've been toying with the idea of puchasing said microscope. Many years ago, I used a Bausch & Lomb Stereozoom microscope with a long arm stand and loved it. I see lots of these for sale and am tempted to spring for one. Is there anything I need to know about picking up a used one? --Chuck

On 6/21/10 5:14 PM, A. Christoff Baumann wrote: I have no problem with that at all. If they DON'T WANT to, that's fine. What I have a problem with is the knee-jerk reaction of "SMT == HARD", which is complete and utter bullshit. -Dave -- Dave McGuire Port Charlotte, FL

"A. Christoff Baumann" <feedle at feedle.net> writes: That's the important thing -- the best way to learn how to handle SMD soldering is to find someone who already knows how and watch them carefully for a while! I'm pretty good at through-hole soldering, but I really struggled with SMD until a friend spent a couple of hours showing me the tricks (in particular, how to use the surface tension of solder blobs to your advantage). These days I find it just as easy as through-hole soldering, even with shaky hands and a fairly modest solder station; it's just a different set of techniques. -- Adam Sampson <ats at offog.org> <http://offog.org/>

On 22 Jun 2010 at 8:09, Jos Dreesen wrote: There are several YouTube videos on hand-soldering QFPs and other packages. The best approach seems to be a wide tip on your iron and some desoldering braid and a very light touch. At least that's what works for me. There are also videos for hand rework of BGAs, including reballing. There's an amazing one of a guy replacing a VIA southbridge chip using what appears to be a butane pencil torch.... --Chuck

On 6/21/10 5:40 PM, A. Christoff Baumann wrote: That's just the thing, though...everyone does. Free (and very good!) instructional videos abound, along with scads of advice on the subject. Mentors are everywhere. And I myself will help anyone who asks. I'm calling bullshit because all I see, eveyrwhere, is a knee-jerk reaction of people screaming about SMT and about how impossible it is and they have bad eyes and blah blah blah blah blah, and most of the time when I ask them if they've actually attempted it, the answer is no. I've had great success with SMT, so when I see people having trouble with it, I try to help. When I see someone complaining about it, my motivation is to ask them what they're seeing and offer advice. However, probably 90% of the time I ask, the person hasn't even attempted it. I do that all the time, actually. :) But thanks for the suggestion. -Dave -- Dave McGuire Port Charlotte, FL

On 6/22/10 11:22 AM, Cameron Kaiser wrote: An excellent point, but do you think it's reasonable to make that valuable something your learning vehicle? One's very first attempt at using a brand-new woodworking tool, for example, shouldn't be repairing grandma's prized living room chair. -Dave -- Dave McGuire Port Charlotte, FL

On 6/22/2010 11:14 AM, Dave McGuire wrote: It's really not the same as having someone show you. There's a big difference between being taught in-person in an interactive manner and having some shaky low-res video one-way instruction on youtube. Yes, there's scads of advice. That's part of the problem. Everyone says something different, there's no consensus and this leads to confusion and frustration for average joe. Since this BS was dumped in my lap originally, let me respond. First, I think your assumption that my (our?) reasons for not liking/not being good at SMT stuff is simply a knee-jerk reaction is unfair. Since you are Mr. helpful, instead of trying to inflame the situation, why not simply ask what the issues are? Try posting some valuable links. Or some encouraging remarks. No, we get, "BULLSHIT", "you don't need expensive tools", "your eyesight doesn't matter." and attacked. On one hand we hear "wrong tools", and in the next we hear that almost any soldering iron will work. As A. Christoff Baumann pointed out, it's great that you've found it easy. Fantastic. I'm happy for you. For the rest of us mortals, these things are hard --- and yes, I've tried and my experience wasn't great. It was an 8-pin SOIC memory chip. I was soldering onto a surfboard. It worked, actually the first time, but I found it pretty tricky and the pitch was HUGE by any standard. When I look at these other chips with tens of pins -> hundreds of pins, I'm intimidated. They are ridiculously close together, and my soldering iron tip looks pretty big next to it. I almost NEVER have a need to do SMT. So not only do I not have a need to practice --- the return on investment is low. Why spend so much time practicing when there are clearly other better/faster/easier methods of obtaining the same (or better) result? Especially when I need a result every couple years? Many people who have already obtained a skill love to claim that what they do is "easy." It makes them look like gods in the eyes of the uninitiated. I'm a pool player. 9-ball is my game. I can break and run a rack of 9-ball on a pretty regular basis. Is it hard? For me? Not really. I do it all the time. How many other people in this forum can do this? I think most people would consider it a "hard task." My 17 years as a player helps this "hard task" become and look "easy." Ok, sure, this is computer forum, but do you see the analogy? Dave: how about a little perspective here? Really? Was that your motivation this time? How about giving us a break? Keith

On Jun 22, 2010, at 9:20 AM, Dave McGuire wrote: Or, if you are just starting woodworking, you might by a kit with some of the harder to do properly pieces pre-assembled and/or precut. Perhaps you might buy this as some 'starter kit' from the local woodworking store, specifically designed to teach some basic skills to a novice while providing the satisfaction of building something useful and beautiful without scaring people off with something that looks hard but might actually be pretty easy if properly demonstrated. SMT LOOKS hard. Regardless of one's personal experience with soldering, the small parts and static warnings all say to the novice "steer clear of this, newbie!" It's not a "knee-jerk" reaction when it is based upon somebody's evaluation of their personal skill level and ability to succeed. Nobody likes to fail, that's just human nature. SMT soldering doesn't look easy, so people steer clear of it. Some of us who've tried it have found our failure rate to be higher than through-hole. Is it within acceptable levels? Probably: every time I've done SMT work, I've managed to fix the flaws pretty quickly (and even spot them before the dreaded smoke test) and I've probably gotten a little better from the experience. I certainly have enough confidence in my SMT skills to do moderate rework on SMT projects, and I've even built a few microcontroller projects that had one or two SMT components. Was it an enjoyable experience? Let's just say I find through-hole projects more rewarding at this stage. I don't feel it is something I (as a three-project-a-year tinkerer) ever will be 100% comfortable with. And that's the point. Everybody has their own skill level, and the novice tends to be very bad at judging theirs, often pessimistically. I, as somebody who assembles and sells kits, would much rather err on the side of caution and hand-hold the novice through the rough spots by pre-assembling the SMT stuff. I've seen one or two P112 boards assembled by novices: they aren't pretty. There are lots of cold joints, lots of excess solder (a sin I'm even guilty of now and then), and just plain look ugly. However, they work.. which is a testament to the design of the P112. I really cringe at the thought of somebody putting on a QFP Z80182 processor using a RadioShack 15 watt pencil with the tip filed down (as was actually the advice in an ARRL publication for inexpensive SMT soldering tools) when they have trouble soldering on a through-hole discrete without lifting a trace or cold-soldering it. Yes, but for many of us, we have 30+ years of through-hole experience and hundreds (if not thousands) of completed projects under our belt. The vast majority of kits I build (including the ones I've sold over the years) are entirely through-hole, in some cases by design. I'm actually working on ramping up production of a kit I used to sell that has a component that is now only available in QFP, the DIP package is long obsolete.. and I'm figuring on either having it robot-soldered on to a DIP carrier for the end-user. (Note that this is also saving me a ton of time having to redesign the board to take a QFP). Maybe I am doing them a disservice. However, once people reach a certain stage with the hobby, they don't need kits anymore, they can just read the schematic, fab their own board, and type the parts list into Digikey. I feel that stage, to use your woodworking analogy earlier, is when they've assembled a good collection of tools and the skills to use them properly. My initial resistance aside, I understand people want the entire experience. Not everybody does: some people like buying raw wood at the hardware store and crafting their project every step of the way. Some people want precut pieces that can be perhaps modified for different results. Some people want completely assembled furniture that is just "unfinished" so they can have the joy of being creative without having to learn woodworking skills. And, some people just like going to a quality handmade furniture store and buying the work of a craftsman, that would far exceed any ability they would ever have in woodworking even if they labored the rest of their lifetime. Point is, just calling 'bullshit' because some people find SMT hard is itself a knee-jerk reaction based on your experiences. Not everybody shares your experiences, nor wants to. And I think that's a big point you are missing in this entire debate. Can we please get back to arguing about how to keep systems "authentic" when buying replacement parts? That argument was much more fruitful and germane.

I do agree with Dave. I just gave a "smd workshop" last saturday and 10 guys who paid to have a tsop IC soldered learned how EASY it is to do with cheap tools. In the age of the 'net and youtube, this is not an excuse. You have HD videos showing the techinics all around, and there is always the cclist for asking around. I'm here to help you, and I'm not dr. Sbaitso :) America is the land of "I'll take your hand for $9,99". There exists, but doesn't mean it is usable or needed. He is so nice, he is giving away to you his help :)

If I bought something described as a 'kit' and found that some (not even 'most') of the components were pre-soldered, I would return the kit and expect a full refund. It's not as descrbed. A 'kit' means I get to build it. Yes, and we had the same arguments when PCBs came in (replcing chassis and tagstrip wiring). Things change (not always for the better, but I digress). I really don't see what all the fuss is about doing SMD assembly by hand. I never had any problems with it at all. -tony

A quick OT question for you steady-of-hand and sharp-of-eye folks, but related to the SMT topic discussed here. I need to jumper a couple of pins on the CPU (Celeron) FCPGA (Socket 370) using #30 AWG wire-wrap wire. How the heck does one do it? My hands just don't seem to be steady enough. --Chuck

On Jun 21, 2010, at 12:42 PM, Tony Duell wrote: I'm not convinced either way on the "reliability" angle. And, I think decreasing the amount of lead in my diet is a good thing, so I'm "okay" with the Pb-free solder nowadays. In my experience of making and selling kits, a lot of people think "hey, if I do that myself, it will make it cheaper." Dave and I have gotten a couple of inquiries along those lines over the years, so I'm heading off that objection in advance. I misspoke: the parts are actually QFP as Dave corrected me. However, given that the board's design is for surface mount parts for the CPU, the FDC, and a couple of discretes, it might require a board redesign, which Dave has indicated to me he's not interested in doing at this point (except for fixing a few of the quirks in the previous rev). And I don't blame him. See my earlier comments about N8VEM: if you want through-hole, there's better designs than P112, double that if you want something more anachronistic. P112 is a more modern design using circa 1995 components. I'll repeat my earlier comment: I think we actually have some blank boards from a previous production run. If people really want a 100% DIY kit, I think we can make arrangements. I don't have any parts kits (you'd have to talk to Dave for those), but I could let the boards go for a pretty reasonable price. E-mail me offlist if interested.

On 22 Jun 2010 at 19:33, Tony Duell wrote: Heh, after I learned that lead-free solder was used by Bosch in my Volvo brick, mysterious electrical problems got a lot easier to solve. All of the relays have been resoldered with leaded solder. The next project is the instrument cluster. Something about the lead- free stuff used not holding up well to years of vibration. It also got cheaper to repair. Instead of buying a new headlight relay for $200, resoldering the PCB in the old one works just as well. --Chuck

On Wed, 23 Jun 2010, Tony Duell wrote: Is that the same warning as the 5150 power supply? If so, how long did THAT delay you? Can you get a cheap one from a wrecking yard? Or get the dealer service manager to save a bad one for you if/when they have to replace one? But the 'universal' solder has lead in it :-) I would assume that for many years, they will be coming out with new compositions of the lead-free solder. Maybe SOMEDAY they will succeed in coming up with one comparable to the stuff with lead in it. Right now, they seem to still be trying to come up with one that is marginally satisfactory. It will take a LOT of practice before I could solder SMT with lead-free solder. I should probably start that practicing, but there are higher priority tasks in the queue. -- Grumpy Ol' Fred cisin at xenosoft.com

On Jun 22, 2010, at 11:33 AM, Tony Duell wrote: There's a lot of stuff still to assemble in a P112. There's a fairly high discrete count, as well as a big handful of chips (RAM, Flash, support ICs), more jumper pins than I care to mention, and the all-important battery holder. When the P112 comes out of the envelope it comes in it doesn't look anywhere near assembled (see a pic at http://p112.feedle.net/pics/kit-parts.jpg). This discussion is now largely irrelevant now, anyway. If you want to buy a P112 kit bare, I've got bare boards and chips on offer, and it is likely there will be enough parts in an unassembled state to meet any demand for them. I believe you've already stated you have no intention of buying one anyway, so I fail to see how further discussion is fruitful. Buy one of the bare boards or don't. My opinion is, and remains, that the P112 in the form Dave and I originally packaged the last production run (and will likely package this one) meets the needs of the people it was designed for. Both of us have received tons of positive feedback from our customers (you know, the people we're doing this for), and it is my belief that it is an excellent bridge between those used to working with modern computer-on-a-chip microcontrollers (the Stamp, Propeller, and Arduino crowd) and the world of retrocomputing. You've done nothing to sway that opinion, and likely won't: further, all the strong talk in this thread of how "SMD as hard is bullshit" and everything else from people who have outright stated they wouldn't be in the market for it anyway has just proven to me that we're doing the right thing for those who do want it. I'd love to be proven wrong and sell out my inventory of bare boards and parts. I somehow suspect my post office box will remain empty for some time.

On Mon, 21 Jun 2010, Geoffrey Reed wrote: No. These are QFPs. The footprint is very different from a PLCC. -- David Griffith dgriffi at cs.csubak.edu A: Because it fouls the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail?