On 6/3/2006 at 1:04 PM woodelf wrote: But it's the parts that aren't RoHS compliant! Tinned leads=bad. That's why manufacturers are slashing production of legacy ICs (can you say DIP?) on a wholesale basis. If you can't sell them in the EU, why bother? I wouldn't fret too much, though. I suspect you could pretty much implement the entire thing in an FPGA with room to spare. Heck, make the switches and LEDs small enough and you could make working PDP-8's for use as dollhouse furniture. Cheers, Chuck

I think it may have to do with nobody actually buying them in quantities more than a handful at a time. William Donzelli aw288 at osfn.org

On 6/4/06, Gooijen, Henk <henk.gooijen at oce.com> wrote: Well... 1/8W RoHS resistors and decoupling caps can't cost that much, and presumably the new "solder" will still wick to gold, so one could still use old gold-plated machine-pin sockets, yes? I don't know about anyone else, but _I_ socketed 100% of the ICs on my SBC-6120. Given the cost of the blank PCB, I didn't think that a few $$$ more for sockets was a burden. -ethan

On Sun, 4 Jun 2006, Bruce Lane wrote: There is no problem in general using RoHS compliant parts with Tin/Lead solder assembly, as long as the RoHS parts do not contain Bismuth (which is rare and may be banned by the next RoHS standards - goodbye Pepto-Bismol) Peter Wallace Mesa Electronics

Chuck Guzis wrote: We also used to have "fluoroscopes" (sp?) in shoe stores. And asbestos siding on houses. And DDT to kill the carpenter ants around the house. And those cute little (oil burning?) cartoon-style "bombs" along the side of the road in construction areas. I think there are moves in places to start putting "recycling fees" on electronic devices. E.g., add $25 to the cost of a monitor and let the user reclaim that $25 by *properly* disposing of it, later. (akin to the 5c fee on bottles/cans in some areas). I see truckloads of electronic devices *allegedly* being recycled that, I am sure, are simply being dumped after someone cherry-picks whatever useful items (resale) they see fit to salvage from the pile -- EVERY WEEK. :-( Just like sweating a joint when plumbing.

Chuck Guzis wrote: Nope. Not prone to vanity :> Though my facial hair is almost stark white (and has been since my 30's) Yup. Kids eat paint...

At 04:39 PM 6/10/2006 -0500, Patrick Patterson wrote: If you're getting 800 messages a day, they are NOT coming from this list! There were about 82 messages today, give or take, up to about 9 PM CDT. That's a far cry from 800. Better run AdWare SE and check for malware. Anti-virus programs don't catch all the bad guys. That's the point of quotations, you know: one can use another's words to be insulting." -- Amanda Cross --... ...-- -.. . -. ----. --.- --.- -... tpeters at nospam.mixcom.com (remove "nospam") N9QQB (amateur radio) "HEY YOU" (loud shouting) WEB ADDRESS http//www.mixweb.com/tpeters 43? 7' 17.2" N by 88? 6' 28.9" W, Elevation 815', Grid Square EN53wc WAN/LAN/Telcom Analyst, Tech Writer, MCP, CCNA, Registered Linux User 385531

Chuck wrote.... I jumped all over it right away and just unsubbed him. Nothing is probably as offensive as suddenly getting traffic from a list that you didn't subscribe to. I did have a "hiccup" with the list server today as I was trying to dig back in to mailman to refresh my memory on how certain parts of it worked. However, he was subbed to the list, and I find it hard to imagine the list just picked his address out of thin air and subbed him. MOST strange. I have no clue what happened there. Jay

Ethan Dicks wrote: With my soldering a socket is a good idea. I just downloaded the PCB manual ... ARG 1/2 Size crystal Oscillators, and none of my favorite suppliers have them.Well one does but it has a $50 min order. I tend to shop at the online surplus places and I don't even think of modern parts. Well I guess I am going to need the whole kit if I buy a SBC-6120.

From: "Alexandre Souza" <alexandre-listas at e-secure.com.br> . comparing of love Actually, lots of boards should not have sockets! For example, the RGB video combiner I'm designing at the moment, even those couple of extra pF can spoil things. I'll also cite early double sided boards, before through-hole plating - it is virtually impossible to solder both sides of a socket. Add anything working above about 10MHz, and you'll have it about right. Oh, and anything you want to be reliable...... Remember all those "I reseated the chips in their sockets and it worked" posts you've seen on this list! Jim.

Good morning, I currently work for an ISP in Eastern Oregon. Today's backroom clean-out day and we have a couple items that may be of interest. Cost? You pay the shipping to get them to you. 1.) Microcom ISPorte, 48 port analog modem rackmount chassis. Comes with (12) 4 port modems and both a spare power supply and a spare chassis. 2.) Computone Inteliserver. 64 port serial chassis. Comes with dead tree docs. 3.) (2) Comtrol 16 port serial cards. Comes in original boxes w/ dead tree docs. Rather than dropping this stuff in the dumpster, we like to find new homes for them. Any interest? Please respond to jamesa at eoni.com with a cc: to jeff at eoni.com Jim Arnott

Like I said in the original post, please reply to <jamesa at eoni.com> with a cc: to <jeff at eoni.com>. I'm just the messenger boy. Jim On Jun 6, 2006, at 3:47 PM, Julian Wolfe wrote:

Chuck Guzis wrote: I'm interested. Peace... Sridhar

Rumor has it that Jim Beacon may have mentioned these words: Virtually impossible? I doubt that - however, there's a few caveats... Why not get wire-wrap sockets that have longer tails, and put a toothpick or popsicle stick under the socket when you solder it (with enough room to remove it later), then it will give enough room to solder the top as well, thereby bridging both layers. Sure, it's a little more labor, but can & does work... Granted, if you were working in a very limited height scenario, one might need to be careful with the extra height. Why 10Mhz? At least in a computer-centric sense, if sockets weren't possible to be used above that freq. how come 2+GHz CPUs can be socketed & work, and 400+Mhz memory can be socketed & work fine? [[ I have no knowledge of audio/analog circuit shiznit WRT stuff like that.... ]] Use machine-turned or machine-pin sockets. Don't blame the socket for all the companies (CouATARIgh ;-) that used cheap sockets... Besides, cheap sockets are still better than no sockets when you need to repair or replace a ROM type chip (CouTANDYgh ;-) but I won't mention any names. ;^> Anyway, reseating chips isn't that difficult of a "fix" anyway... Laterz, Roger "Merch" Merchberger -- Roger "Merch" Merchberger | "Bugs of a feather flock together." sysadmin, Iceberg Computers | Russell Nelson zmerch at 30below.com |

Well, one of the solutions before plated vias was copper eyelets connecting each side. Other than being labor-intensive, I don't know why these still wouldn't work (assuming you could still obtain them. Cheers, Chuck

In message <5.1.0.14.2.20060605135056.0408cb08 at mail.30below.com> Roger Merchberger <zmerch-cctalk at 30below.com> wrote: Another way - get a piece of wirewrap wire (well, I guess Roadrunner wire would be better, but w/w should work) and strip the insulation off of it. Put it through the hole and bend it over in a "U" shape. Solder the top side down to the track and cut off the excess wire. Then when you solder the socket in, solder the wire to the bottom side too (I usually wrap the wire round the socket's pin first). Cut off the excess wire. There you go - a through hole connection. That trick is usually pretty handy when you desolder something and some of the through-hole plating eyelets end up pulling out with the pin. Me neither... I've got some basic analogue skills (mostly related to using opamps for VERY basic signal processing) but ask me to make a transistor audio amplifier and I'm lost... I do however know a lot of the little 'thou shalt not break this rule' type stuff - one decoupling capacitor of between 10nF and 100nF between Vcc and ground as close to the power pins on the IC as possible, and so forth. Well it beats replacing unsocketed chips any day. Swap-in/swap-out vs. cut pins off/desolder/clean holes/install new chip/clean more holes/install/solder/resolder the pad you missed.... :) -- Phil. | Kitsune: Acorn RiscPC SA202 64M+6G VF+UniPod philpem at dsl.pipex.com | Cheetah: Athlon64 3200+ A8VDeluxeV2 1G+180G http://www.philpem.me.uk/ | Tiger: Toshiba SatPro4600 Celeron700 256M+40G

dave06a at dunfield.com wrote: I take it the it is a tossup between a scope and good soldering iron for the first best investment one you get off the kitchen table for projects. The SBC6120 is good reason to get a better iron for me now.

On 6/5/2006 at 2:22 PM Don Y wrote: So, with the fancy irons with solid-state temperature control circuitry, is the Weller TC201 now out of fashion? It's been my faithful compainion for decades--some years ago, I snagged a big batch of assorted tips from a going-out-of-business sale, so I haven't had any reason to change just yet. But is there something that's tons better? Cheers, Chuck

dave06a at dunfield.com wrote: I take it was tossup between a scope and good soldering iron for the first best investment once you get off the kitchen table for projects. The SBC6120 is good reason to get a better iron for me now. PS. I notice most TTL projects are wire wrapped that I have seen on the web rather than having a PCB made.

There was another technique for making circuit boards in the 70s: a programmed/automated machine moved over the initially bare board and laid down a fine wire from a spool to form the circuits. I think the wire stuck to the board initially and the board was later lacquered or coated with something to seal/hold the wires better. I forgot how the wire traces were terminated around IC pin locations, probably a pressure weld. I think the economics were such that it was too slow for large production runs, but was suitable for prototypes and small production runs of larger, more-complex boards. Last example I saw was a disk-controller for a TI-990 mini circa 1980. Anybody remember the name for the technique?

Thanks for all the replies, Multiwire was indeed the name I had forgotten. Rather easy to forget... it's not a very unique name, there being lots of things that could fittingly take on that name. I didn't remember the eyelets at the IC pins, but as Dwight mentions them I have a vague recollection of examining a board and (without knowing better or worse) raising an eyebrow as to the potential for manufacturing (in)consistency and the possibility of either cutting the wire too deeply, or not enough to maintain a good contact. Interesting that there was such a wide range of experience with it's reliability. I wonder if it was board size, or variation in quality control between manufacturers of the boards.

Multiwire. William Donzelli aw288 at osfn.org

I thought Proteon (network vendor) made a lot of their early cards using that "printed wire" technique. I'm probably making that name up but it's what popped out of my brain. Actually I think PWB is what they call PCB's on the other side of the pond. I saw a lot of those cards at MIT at one point. As I recall (dimly) Proteon had their own proprietary wire level protocol (which I'd bet was chaosnet). I think they later went token ring and/or ethernet. But again, I'm hazy on that. -brad

That wouldn't be Printed Wiring Board (PWB) would it? Antonio

Don North wrote: We used multiwire twice for our test boards, 8" x 11" which were usually 4 layer boards, with mostly 14 or 16 pin dips. We had good luck with multiwire, and it was able to run off our wirewrap system, since there was less to be concerned with as far as routing. It was only faster to use an early form of computer circuit board routing and a pcboard, but probably 10 times as expensive. The boards had good electrical characteristics, which was a concern with us, since we were doing a Microdata 1600 type processor plug compatable. I did see some other boards that had the hole to wire problem, but those were on much larger boards, for DG Nova type systems and had much more wiring on it than our cpu's did. Don, thanks for recharging my brain cells about what this was called Jim

Agreed, and even on the "normal" stuff, you still hit pins soldered into large planes etc., so you have to have to be careful. Even so, a very large percentage of the material that I work on responds well to the desoldering station ... It's one of those tools that you can get by with without most of the time, but when you need it it really comes in handy. Quite often I am removing hard-to-find components from junk boards in order to repair a different piece of equipment, and the station leaves both in better shape than my previous method which involved a torch. And no (a response to another post), I didn't say it was THE best investment I have made in my workbench - just one of the best ones. I would put a good fine-tip soldering iron, good storage scope, good mutimeter ahead of it ... After all I went years without it, but I rank it quite "up there" with the other staples now... Dave -- dave06a (at) Dave Dunfield dunfield (dot) Firmware development services & tools: www.dunfield.com com Collector of vintage computing equipment: http://www.classiccmp.org/dunfield/index.html

On Mon, 5 Jun 2006, Roger Merchberger wrote: Most documents I've read on making homemade PCBs discuss doing exactly this by using machined-pin sockets. There's enough metal on the parts side to make it work. -- David Griffith dgriffi at cs.csubak.edu

What is the difference of a "garry" socket hole and a board hole? I cannot agree with your affirmation...

William Donzelli wrote: I think it depends on the quality of the components and construction. I've worked on a lot of military gear that was fabricated out of wirewrapped panels -- one such instrument had 18"x70" hinged panels with everything socketed (except the bypass caps). OTOH, some SIMM sockets are rated for a whopping *6* insertions! think about that next time you're pulling memory! :< ) --don

William Donzelli wrote: I've not noticed that. I use cost solely as the criteria for when to specify a socketed part on a board of mine. But, that is OVERALL cost (which is burdened by in-warranty repairs, etc.) I socket anything that interfaces to the "field" as well as anything that would be too costly to program *reliably* in-circuit (adding ISP adds recurring costs, too, so that's a tradeoff). Anything that is likely to "disappear" during early production or that is export controlled, etc. And, anything that can add value by being socketed E.g., in some markets, it's easier to get a set of DIPs through customs than it is to try to get a whole *board* through. So, "firmware upgrades" are easier to accomplish on-the-sly than they would be with other schemes (relying on FLASH and available machines -- "PC's" -- isn't always appropriate for some markets).

There was (and maybe still is) a valid use for sockets. The "was" was when LSI IC prices were high. There was just too much invested in them to scrap them along with a defective board. This still obtains with CPUs and memory in PCs. At one time, two-channel serial I/O boards for PCs were shipped with one 8250 and one set of 1488/89s. The positions for the second port were socketed. Before that, almost any LSI IC was socketed, such were the economic realities. The "is" is when a ROM needs to be socketed for the purpose of a field upgrade, although flash is making this pretty much obsolete. I can't think of any other reasons. Are there any? Cheers, Chuck

On 6/10/2006 at 9:17 PM Don Y wrote: No kidding. When you get one of those CPUs with the NIchicon electrolyic disease, you pull the CPU and memory and pretty much everything else goes to recycling--well,maybe you pull the button cell. Such are realities. To sell an old PC mobo on eBay, one almost has to include CPU and memory with it--and even then, there are no guarantees. This seems horribly wasteful to me, but then my TV is a Sony from the 1970's. Repairs have been easy and it just keeps going. It survoved a fall off of a table during the Loma Prieta quake (cracked the plastic bezel, but some fiberglass cloth and Bondo took care of that. After a coat of paint, it looks original.) No remote on this one, but there is a mini phone jack labeled "KV-1922" whatever that's for. The portable AM/FM radio sitting on my kitchen table is likewise an old Sony, but this time from the 60's that proudly proclaims "10 transistor". Those are germanium transistors--the unit's powered by 3 D cells, which last about a year or so of daily use. A nylon dial indicator pulley cracked, so I fabricated one from the head of a nylon thumbscrew. That's been the extent of repairs on it--it's quite sensitive--even the dial indicator light still works. But with a modern PC mobo, I couldn't rationalize the time spent repairing it. Cheers, Chuck

On Sat, 2006-06-10 at 21:54 -0700, Don Y wrote: Ah, the dreaded cheap-and-crappy electrolytics. Every so often I take one of my video cameras apart and shotgun a few more electrolytics, and it works a bit better for a few weeks until the next set of dying caps goes. Offtopic: If anyone out there (Tony, I'm looking at you...) has a manual for a Sony CCD-V6000 Hi8 camera, let me know. Gordon.

Not that I am aware of (I think the only Sony video camera manual I have is for a monochrome unit with a vidicon tube that goes with a portable reel-to-reel video recorder -- yes I have the unit, it still works [1]). But I will check. Have you checked the usual companies for such manuals? [1] The heads got wrecked by a wonderful -- NOT piece of corner-cutting. The head design is a bit like a Betamax machine in that the entire drum is stationary, there's a head beak with a head on each end that spins in a gap between the upper and lower drums. Anyway, said head beam is mounted on a disk on top of one of the motors, and said disk is held to the motor spindle by a nut. It should be a left-hand thread (so that it self-tightens when in operation), it's not. If it works loose, the heads clatter against the edge of the top drum with obvious results. Anyway, I managed to fit and align the heads taken from a Betamax head disk onto the origianl beam... -tony

William Donzelli wrote: You're dealing with cheap (inexpensive) consumer products. How did they handle in warranty repairs -- toss the part in a box and donate the box to a local tech school? When you're dealing with something that sells for *many* hundreds or *thousands* of dollars, you look at things differently. I.e. if I have to send someone to a remote village in China to service a piece of equipment because the locals can't just *replace* a hammer driver or analog front end, suddenly the cost of all those "extra insertions" looks like *pennies*! The alternative -- telling a customer to keep a full set of spares on hand -- says a LOT about your confidence in your design! :-( And, makes that product look a LOT more expensive to the customer. Quite different than a market where folks can have a stack of modem cards in a desk drawer as spares -- and another customer down the street to borrow from if need be, etc. My first few jobs were doing field service work and managing a production line. That's where I learned what *real* costs were (ignoring, for the time being, opportunity costs and the cost of "bad will" from your customers). But you are looking at it from a consumer products viewpoint. High volume, drive the cost and quality as low as the market will tolerate. And, if something fails, just replace it (since the labor cost of *repairing* -- not just "retesting" -- a "defective" product exceeds the DM+DL for that product). Imagine the device you are selling is used in a manufacturing environment. I.e. someone relies on your device to make *their* products. Being "down" for an hour, day, *week* can cost more than your product -- even if your product was a few kilobucks. Most manfacturing lines have a hard time justifying a complete set of spares. And, expecting your field tech to carry *everything* that could ned to be replaced makes his job harder (and, more costly to you). OTOH, if your design supports repair in the field, then you have more options available. Customers don't want to have EE's on their payroll *just* in case something needs troubleshooting. *But*, having a *tech* on their payroll who can take direction from someone (over the phone) and replace components without butchering a board (trying to unsolder components) Exactly. And, just like writing code, you have to *measure* before making decisions. Listen to the manufacturing engineer who is SOLELY concerned with his yields and never bears the cost of lost sales, service calls, stocking costs, etc. and you get a stilted view of what the REAL costs are. They are just as guilty of monovision as the design engineer who never walks the floor. Caps are as likely to fail as a socket -- do you keep caps out of a design? *Or*, do you design them in WITH PLENTY OF MARGIN?

William Donzelli wrote: A slot machine loses ~$3000 of business* for each hour it is out of service. Note that most slots are run in 24/7 environments -- you can't have scheduled maintenance (e.g., for a firmware upgrade) "on the weekend". And, consider most locations have hundreds to thousands of slots. Between failures, upgrades, maintenance, etc. it is not uncommon for MANY to be "down" at a given time. Operators do not like this. :> They don't wait for a new board to be flown in. Or, send in a boardset for a factory upgrade, etc. Consider that most organizations require *two* people to be present when a machine is serviced and you'll note that labor can get expensive, quick! In the "gr[ea]y market", most operators have either very few machines (and a "cousin" who can maintain them on their behalf) or a *lot* of machines (and someone that they *pay* on staff for this service). The same is true of arcade owners and folks who run "routes" (i.e. the guy who owns the pinball machines, juke box, video games, candy machines, etc. in your neighborhood bar, bowling alley, etc.). Granted, their gross is typically peanuts (contrasted with a casino). But, that just makes the cost of any repair more significant (if they can't do it themselves). And, of course, the attendant legal-ish issues... Many medical devices are serviced "on site" by the owner's staff. [Not true for devices in a doctor's office (obvious reasons).] Granted, a CT scanner or MRI might require an (expensive!) visit from the factory tech. But, they are lower utilization devices and time on them already is heavily burdened so they can afford that cost (?). But, many of the other little devices (of which hospitals have *hundreds* of different types, models, etc.) are serviced in a shop by techs on the hospital's staff. This is becoming increasingly true of lab equipment as hospitals try to ween themselves from "FREE factory support" for them (the catch is the factory requires you to buy their consummables at grossly inflated prices: "But, this is just distilled water??"). The *direct* cost of not being able to run a battery of blood assays due to down time may not be great (i.e. the cost of those tests themselves) -- but, the cost to the organization may be considerable (if surgeries have to be postponed, beds have to remain occupied, etc.) A tablet press out of service for an hour could, conceivably, result in several *million* dollars in lost product! Most production presses operate in the 50-100,000+ tablet per hour range. But, some can run at rates up to 750,000/hour... that's 200 tablets per *second*! :> Imagine some of these $5 antibiotics cranking off the line at $1000 (retail) per second??! :> (of course, I don't imagine anything other than *aspirin* is produced at those rates as you have to worry about capping, sticking, lost product if your weight control slips for a few minutes, etc.) [realistically, there seems to be considerable excess capacity in that industry so I think a "down machine" is more of a scheduling hassle/inconvenience than anything else] Networking is a niche. Those folks' *sole* interest is in that equipment. It *is* their business. You *expect* them to have hot spares, etc. Their business ceases to exist when that stuff goes down. You expect a carpenter to have two (or *five*!) hammers! But, you probably don't expect him to have two *joiners*! Two expensive for the size business that he has (i.e. himself). Likewise, you can expect a hospital to have a few "extra" EKG monitors. But, not two CT scanners. And, given that they have a LOT of equipment on the premises, it makes sense for them to staff for their own repairs. Many hospitals even have their own labs to calibrate their test equipment, etc. Same holds true of gaming devices... I think you are looking at a different selection of industries than those that I have been involved with. I'm sure Casino operators, hospital administrators (and *especially* little one man "route operators" KEENLY aware of what their costs are since it is their *personal* cash at stake!), etc. have done the math and figured out that they *can* save money by doing these things. E.g., the (closest) local hospital has a staff of 6 just to support medical instruments (they don't even touch PC's, etc.). That's a lot of salary to throw at something that *could* be handled with depot repairs! Consider, a tech has to make close to $80-100K burdened rate. And, by undertaking their own repairs, the hospital has to purchase components, test equipment, etc. In addition, if they *don't* buy in to the vendor's "we'll service it for FREE if you buy our consumables" policy, then you often have to purchase the piece of equipment as well (many devices are "sold" at greatly inflated prices -- with the full knowledge that NONE are actually sold; they are all given away as promotionals to get the consumables in the door!) Sure looks like a HUGE piece of change to invest... *if* they could, instead, have saved all that by outsourcing it. And we all know how EFFICIENT the military is! :> And *my* point is that the total cost of a socket (etc.) figures in many other things -- that the guy walking the floor may not care about but the guy in the front office eventually *does*! Products that have short lifetimes (a cell phone, consumer electronics in general... even network infrastructure!) are usually designed to be replaced in the natural course of business in short order. Other devices with more staying power warrant reduced maintenance costs over those of manufacturing (how many hospitals replace their CT scanners every three years?? :> )

On Tue, 13 Jun 2006 13:05:34 -0700, Don Y wrote: I have been amused by this treread for some time, and this red hot lead in drew me right in to the story, untill I did the math .... $30K per hour is a three coin dollar machine that never stops 24/5. Even my dear old mother can not keep up a 17 bet a minute rate for 24/7 for very long. Slots useage is way down around dawn, and yes I have seen video slots on the floor, shut down, download an update and reboot just in time for the weekend. This last trip $20 lasted about 1/2 hour at the Garfield 2 cent video slot, the Bonus games are well worth it in entertainment. Mom got almost 2 hours out of a nickel mechanical slot for a $20 Now if it is my $20 than 5 minutes max, I'm broke again, I am but the spectator in that enviroment. There is little question that slots rake in the money, but they give a large percentage of bets placed back or people would not last long or return. And when one dies the player just moves on to the next one. It sounds like a nice job, Mom would love to move somewhere with slots :) My wife might take some convincing to change jobs, then again if she could be semi-retired in ther new life :) Take a look at IGT (a nice stock to have purchased a few years back) to see the direction slots have ans are all moving to. Just the other Bob on a slow day ....

At 03:12 PM 6/13/2006 -0700, you wrote: Hey, all you slot machine repair types, anyone seen a manual for a Japan Cash Machine DBA-01 dollar bill acceptor? I have one and no idea how to hook up to the two connectors (one little four-pin and one six-pin in two row with slightly heavier pins. All it says on the top is "DC 12V 9.4VA MAX." It's also got an eight-position dip switch I have no idea how to set. I'd like to make a cool bank for my kid. [Computing] "First learn computer science and all the theory. Next develop a programming style. Then forget all that and just hack." -- George Carrette --... ...-- -.. . -. ----. --.- --.- -... tpeters at nospam.mixcom.com (remove "nospam") N9QQB (amateur radio) "HEY YOU" (loud shouting) WEB ADDRESS http//www.mixweb.com/tpeters 43? 7' 17.2" N by 88? 6' 28.9" W, Elevation 815', Grid Square EN53wc WAN/LAN/Telcom Analyst, Tech Writer, MCP, CCNA, Registered Linux User 385531

On Tuesday 13 June 2006 06:12 pm, Don Y wrote: I've never been that much of a fan of slots, but if it comes to playing on a machine I'd much rather deal with an old-fashioned mechanical pinball machine than any of the video stuff that came along later... :-) -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, a critter that can be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin

^^^^^^^^^^^^^^ As opposed to a 'line of assembly code' (aorry, couldn't resist). More seriously, there is, I will agree, one heck of a difference between prototyping and production. It makes no sense at all to socket most (if any) devices in most production boards. It _may_ make sense to socket rather more stuff in a prototype, or an experimental set-up. I suspect that most of the stuff we do here (related to classic computers, I am not talking about stuff list-members do as part of their jobs) would come under the latter category. If you think of that PDP8-clone board kit that's been discussed here recently, I would think that almost all (if not all) of thsoe will he hand-assembled. Pop each component in by hand and solder it. Nobody (I think) is going to use a pick-and-place machine and a wave solder machine on it. -tony

On 6/5/06, woodelf <bfranchuk at jetnet.ab.ca> wrote: Practice, man, practice (the punchline to an old musician's joke about how to get to Carnegie Hall). They are easy enough to get from places like DigiKey, but I agree that they aren't found in often in surplus shops. -ethan

On 6/4/2006 at 10:07 PM ard at p850ug1.demon.co.uk wrote: That's true--leaded solder will contaminate lead-free and cause it to weaken considerably. But then, that's the case of lead in combination with any other soldering/brazing material in general. When I silver solder (well, actually silver-braze) old botched repairs in brass that were done with tin-lead solder, I have to remove every last bit of the leaded solder before I can braze. Otherwise, the lead will make the silver (56% silver, the remainder copper) braze very brittle and it will fail in no time at all. Cheers, Chuck

On Sat, 3 Jun 2006, woodelf wrote: Maybe the GIDE interface can be adapted for use with this board. It's just a couple GALs and not much more connected to data and address lines. About paper tape, I've been pondering now and then about making a punch/reader that uses cash register tape. Are you saying that using a PC for a terminal is required for this board??? -- 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 Wed, 7 Jun 2006, Philip Freidin wrote: Very nice! It seems like a fairly straightforward and simple project. What are those brass latches on the inside for? Holding the top on? -- 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 6/8/2006 at 11:16 AM Philip Freidin wrote: Didn't one of the first hard disks for the Apple ][ work like that? It was a shoebox-sized unit (drive made by IMI, maybe?). Mapped into something like 50 floppies. So, what does one do with a PDP-8 clone? Cheers, Chuck

On 6/9/06, woodelf <bfranchuk at jetnet.ab.ca> wrote: Plenty of stuff in Dave Ahl's books on BASIC computer games... -ethan

On 6/9/06, Chuck Guzis <cclist at sydex.com> wrote: How about home control? Junk out all the new-fangled X10 stuff, and use your PDP-8/SBC6120 to control your home applicances.. :-)

In the late 70s I used a timesharing operating system called (IIRC) EduComp. This would allow eight users to have access to a virtual PDP- 8 and 32K memory. Is it available somewhere? ----- Original Message ----- From: woodelf <bfranchuk at jetnet.ab.ca> Date: Friday, June 9, 2006 0:15 am Subject: Re: SBC6120 (a build-it-yourself PDP-8 clone) Last Buy and End of Life To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>