On 9/22/10 11:53 AM, Chuck Guzis wrote: What I'm wondering is why anyone would WANT to. -Dave -- Dave McGuire Port Charlotte, FL

On 9/22/10 12:05 PM, John Foust wrote: Umm, yeah, I suppose, but...for what purpose? Eggsperimentation? -Dave -- Dave McGuire Port Charlotte, FL

On 9/22/10 12:15 PM, Teo Zenios wrote: AHH! The light dawns! -Dave -- Dave McGuire Port Charlotte, FL

Somewhere (and I really must find it...) I have a book entitled something like 'Mad things to make'. One of them is a 'bird bombing kite', the payload concists of blown eggs 'filled with an obnoxious substance of your choice' :-). Same book has a design for a 'bubble blowing fish hat', something I really must make and wear... -tonh

On Wed, 22 Sep 2010, Rich Alderson wrote: Thank you I'd bet that you habitually turn screws back to find the start of the threads. -- Grumpy Ol' Fred cisin at xenosoft.com

On Wed, 22 Sep 2010, Chuck Guzis wrote: wild bird eggs have a much lower risk than the half a billion in the supermarkets.

On Wed, 22 Sep 2010, Chuck Guzis wrote: Current students? 0%.

On Wed, 22 Sep 2010, Diane Bruce wrote: My "ViaDisk?" and "DOS boot" lectures were worse. But, I always felt that in mastering DOS (or conquering Gaul) that learning what command to invoke in a given OS was way less important than understanding the relationship(s) between the BIOS, the API/BDOS/File-manager, and the User Interface, as well as a basic understanding of disk format(s), computer history, what trends to expect in the near future, internal commands V "external commands"/programs, batch processing, multitasking, etc. When college administrators asked "Which operating system do you teach?", I was able to honestly (although exaggeratingly) answer, "ALL." In the first semester that I started my lecture with that, I missed it also! I hadn't. Thank you. That's a very nice collection of Mondegreens! Many of those add substantial additional information content to the phrases that they replace. -- Grumpy Ol' Fred cisin at xenosoft.com

On 22 Sep 2010 at 19:05, Diane Bruce wrote: Care to point me to the pun? I got the reference to the opening of Caesar's commentary on the Gallic Wars, but whence he pun? --Chuck

On 24 Sep 2010 at 10:33, Charlie Carothers wrote: Anyone who plays a brass musical instrument with piston valves knows the technique because of the nature of valve end-caps. They're usually somewhere around 3/4 - 1" in diameter with fine machined threads--the danger of cross-threading is great. However, turning the cap anti/counter-clockwise until one hears the "click" ensures success. I suspect that most plumbers know about this when using fine-thread fittings. --Chuck

On Fri, 24 Sep 2010, Chuck Guzis wrote: MOST plumbing is a relatively coarse thread. Screw-mount camera lenses. 39mm x 25 tpi. (39mm x 1mm is a less than perfect fit.)

On Fri, 24 Sep 2010, Tony Duell wrote: Good catch! That would ALSO be a less than perfect fit! I'm pretty sure that the FED was 1mm pitch, don't know about the Zorki, or particularly the early East German counterfeit Leicas. But, IIRC, "T-mount" is 42mm x .75mm pitch "CS mount" is the same, but with 5mm difference in registry (distance to film plane) Some computer parts have metric fasteners, some don't. I don't remember, but I would guess that Shugart 8" and full height 5.25" drives are not metric, but their half-height and 3.5" frives were metric? -- Grumpy Ol' Fred cisin at xenosoft.com

On Fri, 24 Sep 2010, Chuck Guzis wrote: Yes But what I can't remember, . . . Was the Shugart SA400 (and SA390, etc.) imperial, and would Shugart SA455, (&465,475) be considered an American/imperial drive, or a Japanese one?

The classic example of this is the jackposts on HPIB connectors. The male end (to fit into the socket/panel) is often 6-32 UNC (expeically in HP machines), although I have seen metric theads in, say an Epson printer [1]. The female part, to take the screw in the cable connectors is M3.5 (!) now, early ones were 6-32 UNC. The convention for real HP cables/jackposts was taht nickel-plated (shiny metal) screws/posts are UNC, black oxide ones are metric, but I've seen plenty of shiny metric ones on other eqyipment. [1] There was an HPIB interface board for classic Epson dot-matrix printers. It fits into the intenral interface connector normally used for a serial option. -tony

I have never seen a 'real' GPIB cable with anything other than the double-sided connectors and jackscrews. So I wonder what cables this was designed to be used with. Who made it? I have seen a few so-called IEEE-488 devices where the interface connection is made by a 'captive' length of ribbon cable ending in a 24 pin microribbon plng (only). The idea was you put it on the end of the stack of doubel-sdied conenctors on a convenient device. Hmm.. I think the devices I remember this being done on were relatively inexpensive RS232 interface units for the Commodore PET, etc. -tony

As far as I am aware, there is no stnadard command set for HPIB/GPIB/IEEE-488 disk drives. There are 4 that I know of, and probably many others (HP used 3 command sets : Amigo, SS/80 and CS/80, and hten there were the Comoodore drives for the PET). If thios was supposedly an HP-drive compatible device, it would be interesting to find out what it was. -tony

[Leica copies and their lens threads] My guess is that the FED and Zorki are the same, I've never had any problems fitting lens from one to the other, but I don't own the original models. The later ones are not really Leica copies -- they're rangefinder cameras with the same lens mount and register, but the shutter mechanism is very different (for example Leica never made a screw-mount camera with slow speeds on the same dial as the dfast speeds, Zorki did (and IMHO the way it's done is ingenious). Certainly 42mm and a finer pitch... 0.75mm sounds about right. Yes. I've enver actually come across that one, my video cameras have the C mount register. There's also D mount, used on 8 mm cine cameras. Also 32tpi, but a smaller diameter. And I suspect a shorter register. Yes. It's not at all uncommon to find a mixture of threads in the same machine, particualrly when sub-assemblies (PSUs, disk drives, etc) are bought-in. European machines are almost always metric. Old US ones (DEC, HP, etc) are almost always UNC (4-40, 6-32, etc). I have both sets of spanners in my toolkit, along with a set of BA spanners for when I work on Creed teleprinters :-) -tony

On Fri, 24 Sep 2010, Charlie Carothers wrote: Ah Ha! The new generation didn't have Erector sets as kids (the snap-together plastic stuff without a plug-in motor don't count) Any significant amount of play or work with screw fasteners will eventually make it clear. Lack of adequate experience means that one will have to be TOLD such basics. Presumably the same with clockwise v counter-clockwise threads, in an almost counter-productive form. The experienced person will be assuming clockwise, whereas the totally inexperienced are more likely to try both directions. Will the loss of analog clocks have a significant effect on learning CW V CCW? Of course! billetframes.com can make some if anybody else is similarly inclined -- Grumpy Ol' Fred cisin at xenosoft.com

Kids these days :-) I mentioned some months hack that I got my first electic shock before I was 2 years old. By finding a screwdriver and unscrewing a wall socket to see how it was wired. So I guess I learnt early ;-) The really experienced will assume a right hand thread but will check too see if there's any good reason for the theread to be left-handed, particularly if it would undo when turning it anticlockwise. There are some LH threads in calssic computers. In particular the spindle bolt in some 5.25" disk drives (like the ones used in the IBM PC/AT) re left handnd. I've seen left-handed taps and dies on sale. And of course it's easy to cut a left-hand thread on a lathe. But I have never seen LH nuts an bolts listed by any company in the UK. But I've not seriously looked for them. -tony

The point of LH screws is not to confuse poor hackers who want to take the thing apart. You know my views on dismantling things well enough, and I am not going to hinder others from doing the same :-) You use LH scres in places where RH screw would tend to be loosened by the movement of the parts concerned. Like that 5.25" disk drive I mentioned. Such cases are not common, but they do exist. As an (odd-topic) aseide, the Sony EIAJ reel-to-reel video recorders have a metal disk mounted on a spidle by a nut and lockwasher. The head beam fits onto the disk 9and is held down by 2 screws), the head tips then go round a slot beteen the 2 stationary drum parts. That nut really should be left-handed (it isn't) becuase it's naturally loosened by the mocvement of the parts,and if it comes loose, the head beam goes askew and the head tips get shattered as they hit the drum. Don't ask how I found this out... -tony

:-). I harv, of course. cut plenty of threads... Male threads can generally be cut on lathe if you dont have the right size die (even if you do, it's good practice to cut them to most of the depth on the lathe and finish them with the die). Female threads can also be cut on a lathe but only if they're over about 10mm. Below that you can't fit the cutting tool into the hole. Nuts of all shapes and sizes are easy enough to make (although even I don't make things that standard M3 nuts myself.). Cutting the threads on bolts is also quite easy, the problem is making the head. Hexagon heads (of any size) are not hard, nor are slotted heads for a normal screwriver.But making Allen socket heads, Torx heads or Phillips/Pozidriv heads really neads a suitable punch and a press. A web search should find soemthing. I know a company who claims they can get LH taps and Dies for, IIRC, 3* the price of the corresponding RH one. In generaly you buy these individually, in the sizes you need. Evil ! -tony

The thread direction and size are meaningful with air fittings. Look it up before monkeying around with it. -- Will

Left handed threads on flammable gases are an exercise in Darwinism. Think about the guy with a cigarette in his mouth who smells gas, so he turns the gas fitting clockwise.

On 26/09/2010 3:34 PM, Chuck Guzis wrote: Put the valves back, and just say you have water from Austraila. :) ben

Fred Cisin wrote: I suppose I like to think that nobody who isn't trained in the equipment would be allowed to mess with it - but if they've got a cigarette dangling from their mouth at the time then they probably deserve everything they get :-)

On Mon, 27 Sep 2010, Jules Richardson wrote: BBQ with hose to propane bottle? . . . or at least the survivors can sue the tobacco companies :-)

On 9/27/10 3:27 PM, Tony Duell wrote: "I'm highly educated. I just didn't get that education in a school." Our society is quick to dismiss any learning that doesn't happen within the four walls of a school. Or worse yet, they insist that it's impossible to learn in any other way. This is complete bullshit, of course, but like the Emperor's new clothes, most companies don't want to admit that it's the non-degreed fellow in the low-paying position that keeps the whole place running, rather than the expensive PhD (present company excluded of course!) whose hiring resulted in a press release. -Dave -- Dave McGuire Port Charlotte, FL

I could certianly claim the second aprt of that. The firsr part is open to debate ;-) However, I would argue that there is a difference betwene education and training in that the second implies (at least to me) being shown how to do something and being expected to follow that procedure. Mind you, I do have a license for 'self training in wireless telegraphy' :-) Tell me about it. It really annoys me. The powers-that-be need to realise that there are people who ahve taught themselves things to a very high level, and are quite capable of applying that knowledge... Put it this way : You need to emply a guy as a C++ programmer. Who would _you_ rather have : A chap who has a bit of paper saying he knows C++, based on the fact he did a 2-week course in the language, but has no other programming experience A chap who's never written C++ and has no programming qualifications at all. On the other hand he's taught himself to program in serveral languages and has written many thousands of lines of plain C. I know who I'd rather have. And I know, alas, who the HR department would pick. ACtually, I could argue that a Ph.D. at least the way I, and my parents, did it involves a lot of self-teaching, and a lot of hands-on work. Maybe some don't, though ;-( But a first degree (BA/BSc) over here involves almost no origianl thought or hands-on expeirence at all most of the time. And it shows, I despair when I hear of people with degrees in electronic engeineering who've never soldered antything toghter, and people with degrees in mechancial engineering who wouldn't recognise a lathe if it got up and bit them. -tony

Ouch!. There's also the widely-held belief that learning to program mainly invloves learning where to up the semicolons in a C program (or equivalent). Whereas to me (not a programmer, I admit), that's something you can look up if you need to, and 'programming' is much more about how to analyse the problem, choose suitable algorithms and data structures , and express those algorithems in the chosen language. Actually getting the syntax correct is a minor part of it. And we wonder why this world is in a right old mess... Ahm you said much the same thing. I wonder if that;s a worldwide problem. At least over here, the Ph.D. work is supposed ot 'advance the subject' in some way. I was perhaps lucky in working a department run by, and containing people who had no objection to getting their hands dirty (literally sometimes...) -tony

----- Original Message ----- From: "Jules Richardson" <jules.richardson99 at gmail.com> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Sent: Tuesday, September 28, 2010 8:54 AM Subject: Re: Screwing around (Was: Multimeter recomendations There are different levels of training. Lets take the propane grill for example, anyone can pretty much turn on the gas and hit the igniter and then cool a steak. Some people who tinker can adjust the air fuel mixture by moving objects or making different sized holes to make the grill a little hotter or cooler running even by trial and error. And then there are those who know the theory behind combustion and can calculate the perfect orifice valve without blindly changing things that could lead to explosions (because of air/fuel mixtures) and can even convert the grill from propane to natural gas. So you have operating knowledge (user), maintenance and proper setup knowledge (technician), and in depth design of combustion material and flow metering (engineer), and even possibly advanced theorists who know all about combustion period (scientist) if we needed to cook using alternatives to a common grill (also needing the engineer to then design it, the tech to set it up and adjust it for proper burning, and a user to cook the steaks after everyone else fought over who was more important). Screwing around is how many things were discovered over the centuries, but doing it blindly is also how many people end up dead.

I think I've mentioend before that these days my parents would probably be guilty of child cruelty or something. My 8th (I think) birthday prsennt consisted of things like a woodworking tenon saw, a junior hacksaw, a set of twist drills, a wheelbrace (hand drill) to use them in, a small vice, and so on. Yes, I ahve cut myslef with them over the years. But no, I have had no serious injuries from tools ever... And I do thank my parents for encouraging my hackish tendencies. I certianly think there are fewer constructional toys around now than there were perhaps 30 or 40 eyars ago. I must have over a dozen different educational electronics systems, and none of them are Heathkit :-). As I've said before, I think the Philips EE kits were the most fun, but teher were others. And there were many more electronic kits (as in solder a device together) around back then than there are now. It's dubious how mucyh electronics you learnt by assembling a Heathkit, say, but you did certianly get practice with tools, and you might be inpsired to find out more about what you were doing and why. Be careful!. LH threads are always ued for a reason, not becuase the manufacturer is awkward. I don;t know aobut compressors, but I rememebr there is some convention with gas cylinders and the regulators for those. There are LH and RH threads, IIRC oxygen/air/oxidising gases is one, 'fuels' like acetylene, etc is the other. The idea is so you can't accidentally couple up the wrong one, or put oxygen into a regulator that has been lubricated with oil (compresed oxygen and oil can catch fire or explode). It's been a long time since I worked iwth gas cylinders, so I cna't remember the details, but I can check. So I would not modify anythread in a compressor unless you really know what you are doing. -tony

Depends on the parents. My folks refused to get us an NES when we were younger, and wouldn't even let us rot with the old Intellivision. They got us Legos and Construx, and forced me to learn how to use the C64 ("we spent a lot of money on this, and you will damn well learn how to use it"). I'm eternally grateful to them. Truly. -- ------------------------------------ personal: http://www.cameronkaiser.com/ -- Cameron Kaiser * Floodgap Systems * www.floodgap.com * ckaiser at floodgap.com -- You cannot trust this technology stuff. -- Ira Oldham ----------------------

On 9/26/2010 4:21 PM, Fred Cisin wrote: I suppose there are some advantages to having been born in 1938. :-) I still think the Erector set I got for Christmas when I was about 10 was about the best present I ever got from my parents. After they passed away in 99, when I was cleaning out one of their storage buildings I rescued it, and I still have what was left of it out in my garage. The last thing I built with it (a windmill) is out there too. With the little electric motor on the base driving it I'm sure those unprotected metal "blades" would be considered way too dangerous for a kid today - even though the drive "belt" was (I think) just some string. IMHO, everyone should learn to keep their hands out of obviously dangerous places, and learning that at a fairly young age is not a bad thing. I had a pretty fun chemistry set too, but I always liked the Erector set better. I could never get some of the "experiments" to work, but the Erector set projects always worked...

On 9/27/2010 1:14 PM, Fred Cisin wrote: That is quite true, though I can't recall ever hurting myself with those either. I have the feeling somehow that just tinkering with such things at an early age helped equip me to behave safely when later in life I worked around some much larger, much higher powered, and therefore much more dangerous open gear and drive belt situations. That sounds about right. It is definitely mains powered, and I'm pretty sure the motor is sort of pale blue or blue/gray. I think some of the color on the little frame that holds the gears may have faded quite a bit over the years and/or the paint peeled off. The gears do slide back and forth on shafts, and ISTR there are set screws to clamp them where you currently want them. I think there may be collars with set screws on the outside of the frame so you can move the shafts to different hole positions as well. Later, Charlie C.

Ah, but to they? Or is it that kids today are only offered totally mindless toys (like most electronic games) and don't realise there are other things they could be doing. I wonder how many kids would like boulding things, etc, if they were given the chance. FWIW, my favourite constructional toy was FischerTechnik. I never had enough to do everything I wanted (it was very expensive in the UK), espcially the electronics modules. I made my own versions of some of them, and I sometimes wired up circuits on stripboard and connected them to the FischerTechnick motors, etc. Yes, I still ahve all the FT I ever owned. Still use it sometimes, along with the commerical BBC micro interface I bought on E-bay and the homebrew HP48 interface. I did once ask for an get an electronic game. It was the Milton-Bradely 'Microvison' (nothing to do with the Sinclair pocket TV). Stece Ciarcia has mentioned it in his article on LCD displays, and I wanted to investigate the display in this game. It's a 16*16 dot matrix device, at a time when such things wrre not ocmmon. The main unit contains a custom driver chip only, the cartrige contains a TMS1000 microcontroller. It didn't take me long (even at that age) to work ou the basic connectoions between them (given the TMS1000 data sheet), and from said data sheet I discovered the TMS1000 could be clocked as slowly as you liked. So I added a larger capacitor to the clock circuit to slow it down, and hung LEDs and series resistors off the TMS1000 pins that went to the display driver. I think I got it to change state at <1Hz. I then wrote down the patterns and eventially made sense of them (it's soemthing like : Send 8 nybbles t odefine the state of the 32 lines going to the display, the first nybble has a sync line set also. Then sent the complement (to drive the display with AC), and repeat.) Doing that was much more fun that playing the 'breakout' game that came with it :-) Did I mention that I rarely used (or use) my toys as expected... That'as basically my point. You won't learn muc electroncis just soldering up a Heathkit or somilar, but you will get to see and handle the components, you'll use the tools, and you may get interested in finding out more. And then you start reading books on electronics, and so on. I certainly feel you're more likely to want to find out about electronics if you've assembled a few kits than if you haven't. At the start of this year's HPCC conference I quoted a paragraph from 'The Voice of the Crystal'. Basically it said that people (as a whole) have never been better educated, and that there's never been more information available, but we don't know how to _think_ any more. Unfortuantely I feel that is exactly right. -tony

Exactly. That's what the quote was saying (and I agree with it). Today : People are provavly better educated than any time in the past There is more indromation available than at any time in the past But : People no longer think :-( Ouch!. I can remember buing various databooks in the mid 1980s (Texas TTL, Zilog microprocessors, Motorola 8-bit processors/peripherals and so on). They were typically \pounds 15 to \pounds 20 each. Quite expensive for a schoolboy at the time, but cheaper than you had to pay. -tony

Those are hardly exotic tools :-) I think it is still available. A few years back I was in a Lego shop in, IIRC, Bluewater (a larger shopping centre to the East of London) and they certianly had it. In fact you could buy an empty box form them in various sizes (cost more as it got larger) and fill it with yor own assortment of parts, and the Technical gears, spindles, etc were there. The first version of Lego Mindstorms used the nroaml Technical mechancial bits. I have no idea what the latest one uses. Of course. Hackery does not come from follwoing the instructions :-) FischerTechnik, alas, went the same way. The stuff I grew up loving was very general-purpose with few custom aprts. Even the electronics stuff was things like relay moduels, analoughe comparator modules, etc. Now, apprently, you get a pre-built and configured black box for the projects in that kit. Bletch!. Maybe after I desing a multimeter I should design an educational construction toy. Now, should the basic kit include enought bits to make a fairly accurate mini-lathe so you can make more parts yourself :-) I know them.... I always preferec the Philips kits becauise the components weren't pre-mounted (as in thost bendy-spring ones) or hidden inside modules (Electroni-kit, Braun Lectron, etc). With the Philis EE kits you got to handle and conenct 'loose' resistors, capacitors, etc. OK, the transistors (BC148 and BF194 in Lokfit packages) were pre-soldered ot little PCBs that fittedo not the spring terminals, but everything else was just 'real' components. So of course you could trivially add extra components yourself... The kits I had had some interesting projects including both common forms of AF signal generaotr (diode-mxing a pair of RF oscillators and taking the beat frequency ; The Wein bridge osicllator with a lamp to stabilise the gain (OK, it was transiotrised, but it's nice to have a kit that lets you build something a bit like an HP200) and various suiperhet radios (most enducational kits don't go beyond TRF recievers). I never had the add-on kits that weren't sold in the UK, like the one with the CRT or the TV tuner module... To get the sliightly closer to being on topic, has anyone else here come acros the Philps CL1600 series of eductional digital electronics modules? -tony