test-drb January 2005

test-drb@ccmp.vtda.org

254 participants
551 discussions

by classiccmp＠crash.com

Sellam Ismail wrote: . > I can make a really good argument ... that e-mail could never have > gotten as big ... as it did without the modern (1990+) Internet, > which could not have gotten where it is today with Linux. I assume that was supposed to be "without Linux." I'll bet someone like Tom Jennings will have a totally different take on this than I do, too. [ Ah, there's his note... Clearly I've been editing this response too long. ] Where to start... I disagree about the growth of the Internet not being possible without Linux. It would have been different, perhaps, but I honestly don't think it would have changed enough to surprise someone who popped into a Linux-less parallel universe as regards email and the Internet. Might have changed a lot more regarding the popularity of open source software, but that's a different discussion. I think that the growth of email and the Internet in everyday life rode two big trends. One is the rise of CompuServe and AOL, which I'll leave for another discussion. The second was the rise of small scale ISPs in the 1993-1994 timeframe, at least in the Northeastern US, and that they were offering raw dialup IP connections. They'd give you a POP account, maybe shell access, and that set the stage to a great degree for non-corporate, non-academic participation in the Web when it came on-stage. Regular folk with Windows/Mac machines were signing up for these accounts, not just tech weenies, for all the reasons that email was popular. No long distance charges, asynchronous between sender and receiver, faster than the post, etc. I recall some who were downloading freeware and shareware like crazy, but the major thrust for this non-tech segment I observed appeared to be email, with some IRC/chat junkies. This led a gentle but steady ramp that was ready to explode with the advent of Web browsers. And the low-usage email customers were what supported the model, not the high-usage geeks who would try to nail up connections all the time for the low-ball prices. Why don't I think Linux was a major factor in this? Surely many of these ISPs used Linux? Well, maybe so. The ones I dealt with would use whatever they could get their hands on to provide the backend services they needed, and didn't care what they had to use to do it. No Linux? Hey, that free thing 386BSD works, or this 1993 fork called NetBSD. But to be honest, most of the time they very, very grudgingly spent the money for Sun gear, at least for the most critical machines/services. And then ran them without any service contract or spares on-hand, which always made me cringe... At least, this is what I ran across in my adventures, your mileage obviously varied. But again, I wouldn't give Sun credit for the spread of the 'Net and email either, for the same reason. If it hadn't been Sun, it would have been something else, and I ran into odd bits of DEC and SGI here and there. I think there were several factors coming to bear, like the NSF AUP changes, like the appearance of PCs with IP stakcs in many more homes, like falling prices for the low-end leased lines that the new ISPs depended would massively oversubscribe... ;^) You want a technical change to point to? I'd point to TCP/IP coming to Windows and the Mac. (Yes it had started much earlier, but it was now getting easier and more reliable.) I'd point to terminal servers getting good SLIP/PPP and connection accounting support. And whatever it was that prompted the Baby Bells to start providing DS0 lines and fractional T1 loops to anybody who could scratch up the cash, if that was in fact a technical change. Would many companies have done things differently without Linux? Sure. But even so, I think it would have happened at a slightly reduced pace with *BSD under the cloud of the USL/UCB lawsuit and the high price of a BSDI license -- which when I looked at it was closer to $1,000 per host, not $100 for a site license! (Might have been a built-in support cost, memory is fuzzy...) The hardware savings alone would have continued to make that a compelling combination versus $10-20k for Sun workstation. Okay, I've spouted off enough for now. I'm curious to see what other responses come in, and what others remember from that time, now as on-topic as anything else since it's more than 10 years ago. Gulp! --Steve.

19 years, 7 months

Fabricating with plastics

by kyrrin＠bluefeathertech.com

Been following the discussion on fabbing HV assemblies with plexiglass. There's another type of plastic called 'Delrin' that's very hard, very durable, has high temperature resistance, and it machines, drills and cuts as easily and cleanly as aluminum (better, in many cases). I used Delrin blocks to fabricate the insulators for a high-current diode isolator bank. While that application was high-current/low-voltage, Delrin's dielectric strength is huge. It's rated for 380V/mil in that regard, and it has a resistivity rating of 1x10 to the 14th ohms per centimeter. I don't see any reason why it would be unsuitable for high-voltage insulator assemblies as well as high-current. Keep the peace(es). -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner & Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m "If Salvador Dali had owned a computer, would it have been equipped with surreal ports?"

19 years, 7 months

Original TV Typewriter

by swtpc6800＠comcast.net

I have added more information on Don Lancaster's original TV Typewriter to my web site. http://www.swtpc.com/mholley/RadioElectronics/TV_Typewriter.htm I have put up the complete set of plans, the 24 page booklet you had to send away for. http://www.swtpc.com/mholley/TV_Typewriter/TV_Typewriter_Reprint.htm I have 300 dpi and 600 dpi tiff files but they are very large. Ask if you want them. There is a real copy on eBay now with a starting price of 1.95. (Item number: 5744207804.) I already have two copies so I won't be bidding. I also have some pictures of a real TV Typewriter build by Bob Rethemeyer. http://www.swtpc.com/mholley/TV_Typewriter/Rethemeyer.htm Michael Holley www.swtpc.com/mholley

19 years, 7 months

Data recovery on Toshiba T3100 laptop

by dave04a＠dunfield.com

>Hello, cctech! > >I recently recieved a call from a friend of a friend regarding a laptop >that has come into her posession after a coworker of her died. She was >doing some sort of environmental research, and all her work is stored on >this computer. > >I tried taking the path of turning it on and just doing a copy that way. >No such luck - the plasma display has a garbled and not stable display - >text is garbled to the point that I can't read it, and it basically >looks like it's about to go straight to hell. It does boot from harddisk >- I feared that the plasma might be sensitive to power variations or >something like that, and thus tried getting the machine apart. > ... >Is the floppy drive 1.44M? If it's a T3100 (8Mhz), the floppy drive is 720k - if it's a T3100E (12Mhz), the floppy drive should be 1.44M. If it boots to DOS, or you can get to a DOS prompt (ALT-F4/Enter in Win 3.x), then you should be able to communicate with the DOS prompt via a terminal on the serial port: CTTY COM1 [I recall that the default speed is somewhat low, but it won't really matter as long as you can figure out what it is with your terminal emulator - if you like you can blind-type a MODE command first to set the serial parameters] Once you get to a DOS prompt, you can format diskettes and copy files to them - Don't try to run any non-command-line software! Another option would be to use INTERLNK - you can "blind type" the MODE and COPY CON: commands required for RCOPY and then run INTERSVR, or you can prepare a DOS boot disk that runs INTERSVR in the AUTOEXEC and boot the machine from floppy. You could also use the boot disk approach to get LAPLINK running on the machine etc... As long as the machine is still actually running, it shouldn't be that hard to get the data off - Enjoy the LSI-11. Regards, -- dave04a (at) Dave Dunfield dunfield (dot) Firmware development services & tools: www.dunfield.com com Collector of vintage computing equipment: http://www.parse.com/~ddunfield/museum/index.html

19 years, 7 months

Troubleshooting an IBM 5155 - (portable personal computer)

by CCTalk＠catcorner.org

> From: Fred Cisin [mailto:cisin@xenosoft.com] > Sent: Saturday, January 15, 2005 2:59 PM > > > Now, by disassembling and cleaning the B: drive, I was able > > to get the machine booting off this drive (cabled as A:). > > However, the same cleaning procedure on the A: drive did > > not allow it to boot. I still have to clean > > the heads. Maybe that'll make a difference. If not, I think > > I may have other Qume drives without the IBM monniker on > > them that I can swap the bezels with. I just have to dig > > through the cabinent and see what'll fit. > > THe early, original Qumetrak 142 drives have my nomination > for the second > to worst drive ever, coming in right after the early versions > of the BASF 2/3 height drives. > The Qume drive was SO slow, that PC-DOS 2.10 had to extend > the times to prevent timeouts on normal disk I/O. Well, I just went through the "closet-o-drives" and I don't have any other Qumes laying around. Furthermore, the DS/DD drives I do have the card edge connector on the wrong side. The included cable is not long enough to plug one of these in and leave the one working original drive. Does anyone have the service manual online for this drive? I would really like to get the Qume drive working, but don't know where to go next. I guess I could swap the boards between the two units, but that'll only tell me if it is electronic or electro-mechanical. Other than that, any suggestions for figuring out if it is alignment, broken sensor, or something electrical? Here is what's happening with this drive: The computer goes through it's mem-test, then advances the head. The head retracts, then the system immediately dumps to cassette basic. It doesn't even seek again. I don't have an oscilloscope handy, and wouldn't know exactly what to look for anyway. Thanks for any help. Kelly

19 years, 7 months

Troubleshooting an IBM 5155 - (portable personal computer)

by dave04a＠dunfield.com

>Other than that, any suggestions for figuring out if it is alignment, broken >sensor, or something electrical? IIRC, you mentioned that the other drive works, and you were able to boot DOS? If so, setup the faulty drive as drive B:, boot DOS, and try formatting a blank disk in the B: drive - if it works and you can read/write files to the drive, the it is probably just a little out of alignment (You will probably find that the disks it makes cannot be accessed on other drives). Assuming this doesn't work, what error message does DOS give whwn trying to access the drive? Also, normally the system will try much longer to access the drive if it is seeing sector pulses - if it behaves pretty much the same with the diskette in as with it out, then you may have an index sensor problem. With power off, manually move the head out some distance from track-0 - does it step back when the system starts - does it perform the "Seek test" at power- up and does it look and sound exactly like the other drive? - if no to any of these, perhaps there is a problem in stepping/track select, track-0 sensor. Also, "scopes are your friend" - of you have one, take a look at what is going on at the interface when you try and access the drive - you should see the select line go low, look for index pulese, step pulses, track-0 detect, data >from the drive etc. - it might be fairly obvious what the problem is. I assume you have already done this, but clean the head, and check all connectors for even a little corrosion (edge, head, steppers etc.), especially if it has been sitting around for a long time - same goes for config jumpers and option blocks A good cleaning often does wonders! Regards, Dave -- dave04a (at) Dave Dunfield dunfield (dot) Firmware development services & tools: www.dunfield.com com Collector of vintage computing equipment: http://www.parse.com/~ddunfield/museum/index.html

19 years, 7 months

Data recovery on Toshiba T3100 laptop

by dave04a＠dunfield.com

>> Set it up on two working computers to get the cable and two boot >> floppies correctly configured. Not easy, but you'll never have to do it >> again -- just boot the floppies. > >Assuming INTERSVR configures one of the serial or parallel ports properly >upon booting... It should, as the T3100 ports I believe look like standard hardware (I can set it up and get it working if you want me to verify etc.). Worse case, you can set ports and serial speed on the command line, so it might take a few tries with the boot disk - but you should be able to get it working. Regards, DAve -- dave04a (at) Dave Dunfield dunfield (dot) Firmware development services & tools: www.dunfield.com com Collector of vintage computing equipment: http://www.parse.com/~ddunfield/museum/index.html

19 years, 7 months

Troubleshooting an IBM 5155 - (portable personal computer)

by CCTalk＠catcorner.org

OK, for a little on topic. Before I go tearing the whole machine apart..... I am the proud new owner of a nice example of the IBM 5155. This thing is in pretty good shape. Turned it on, A: did a quick seek and the I was into BASIC. So far, so good. Now, I'm trying to boot DOS. I have several known good DOS 3.1 boot floppies on 360K disks. I keep an old 486 with a 360K drive just for this (and for creating disks for my Tandy model 4). Anyway, the original A: drive only gives a "boot failure". The B: drive (after a cable swap) boots sometimes. Taking out these drives looks to be a MAJOR undertaking. Not along the lines of multiple years, but they are pretty securly installed. However, I'd like to keep them because they have the IBM faceplate. Now, for the questions... Are these Qume drives subject to any known failure? Should I just dig in, remove these drives and give them a good cleaning and lubricating? I'm used to working with the big 8" drives, where everything is a bit larger. What is the best way to clean the heads? Lint free swab and 90% Isopropyl alchohol? Cleaning disk? Nail file ;-) What's the consensus? Any suggestions or comments in general about this machine? Thanks, Kelly

19 years, 7 months

Nova 4 system

by ICS＠Core.com

Anyone have any news about the fate of the Nova 4 system in Bakersfield? ,George

19 years, 7 months

Troubleshooting an IBM 5155 - (portable personal computer)

by CCTalk＠catcorner.org

> From: John Allain [mailto:allain@panix.com] > Sent: Saturday, January 15, 2005 9:59 AM > > > Any suggestions or comments in general about this machine? > > I gave myself 30 minutes to get one of those going once. > I got access to just about all subsystems/components in that time. > The coolest thing that really made me like the machine was that the > video monitor was IIRC 5V,NTSC in, picture out. Very easy to use. You're correct about disassembly. It was much easier than I thought. The biggest problem was getting to the drive mounting bolts on the side by the expansion cards. After removing all the cards, there was just enough room for a socket and ratchet to fit in there. > - - - > You might want to try Rewriting fresh floppies on a true 360K drive, > heat,time, and 1.2M drives all can degrade the data to some degree. I do use a 360K drive in my 486 just for creating these discs. I guess I wasn't clear on this. Now, by disassembling and cleaning the B: drive, I was able to get the machine booting off this drive (cabled as A:). However, the same cleaning procedure on the A: drive did not allow it to boot. I still have to clean the heads. Maybe that'll make a difference. If not, I think I may have other Qume drives without the IBM monniker on them that I can swap the bezels with. I just have to dig through the cabinent and see what'll fit. > > John A. > Thanks, Kelly

19 years, 7 months

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test-drb January 2005