test-drb May 2005

test-drb@ccmp.vtda.org

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If not IBM then Who was First

by jrkeys＠concentric.net

Most people give IBM credit for the Sept 1956 creation of the RAMAC as the first hard drive but is that true?

19 years, 1 month

another ebay weirdness

by quapla＠xs4all.nl

Uhhmmm.... http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=1247&item=5201935487 (not afiliated btw)

19 years, 1 month

cleaning my storage in boston, dec & sun workstation gear avail.

by akb+lists.cctech＠imap1.mirror.to

OK, I'm cleaning out and downsizing my storage space. It's just north of Boston, Massachusetts. Stuff I know I have way too much of, free to good home: 10? Vaxstation 3100 model 30 10? DECstation 2100 10? DEC VR262 19" mono fixed freq monitors 8? Sun Sparcstation 10 and 20, also probably sparcstation 1 & 2's 2 Sun Sparcstation ELC 2 Sun 3/110 2 Sun color monitors with 13W3, about 17-19", I forget model number 1 Fuji Supereagle 1 JDL 850 printer/plotter 1 Sun 4/260 VME system, various extra VME boards 1 19" fixed freq color monitor, rasterops I think 1 HP 9000/400, FSF surplus Most machines have a small working scsi drive and I have a fair number of keyboards, mice, scsi shoeboxes, umbilicals, etc. which I can pass on to people who take CPUs. The dec boxes mostly don't have an OS on them, I'm not sure about the suns. The suns may also have cd drives and/or floppies, the decs don't. Stuff I probably also want to get rid of, but am not as likely to dumpster in the next few weeks: 2 DECsystem 5300's (MIPSfair) 1 uVAX II in BA123 1 Sun/Hitachi 19" fixed freq monitor 1 Cut Sheet Feeder for Epson LQ-800. Also the LQ-800 itself. :) 1 or 2 Vaxstation 2000 or uVax 2000's. several cases of 8.5*11 plain white tractor feed paper Where else should I post this besides here and a.f.c and craiglist? Write to me at google at mirror.to if interested... --akb

19 years, 1 month

Remembering RAMAC

by news＠computercollector.com

Nice article about the (first?) hard disk in today's Mercury News: http://www.siliconvalley.com/mld/siliconvalley/11743962.htm ----------------------------------------- Evan Koblentz's personal homepage: http://www.snarc.net Also see http://groups.yahoo.com/group/midatlanticretro/ *** Tell your friends about the (free!) Computer Collector Newsletter - 725 readers and no spam / Publishes every Monday / Write for us! - Mainframes to videogames, hardware and software, we cover it all - W: http://news.computercollector.com E: news at computercollector.com

19 years, 1 month

Neon bulb logic elements link?

by James＠jdfogg.com

> > The site that had some scanned pages from a book, about using neon > > bulbs as logic elements. I planned to read it later, and then lost > > it. Anyone seen that site? > > You mean the stuff in this zip file? > http://computer-refuge.org/classiccmp/neon_lamp_logic/lamp.zip I seem to recall that neon's behave as diodes. I might be wrong. ---- There are only 10 types of people in the world, those who understand binary and those who don't.

19 years, 1 month

zip now Archival quality printing

by mamcfadden＠cmh.edu

One of my thoughts was to take an archival quality black pen and insert it into a pen plotter and use archival quality alkaline paper. Write out information, kind of an automated "monk" except they don't have to take time off for prayers, sleep and food. I think you need contact of the writing instrument against the paper. The pressure of the pen against the paper helps define the lettering. The paper fibers hold the ink. I have heard about using inkjets with "archival quality" inks. When using an inkjet you have to work about clogging jets, drying time, bleeding of the ink, and fading. There are existing examples of "old" books that have survived nearly intact and I think the idea is to keep it simple. Keep the pen and paper paradigm. Once I was able to hold and read a book that was over 400 years old it made me feel a connection with the person who expended the effort to create it. They did a lot of work and I was able to read it 400 years later. Mike

19 years, 1 month

Neon bulb logic elements link?

by ajp166＠bellatlantic.net

> >Subject: Re: Neon bulb logic elements link? > From: "Eric Smith" <eric at brouhaha.com> > Date: Wed, 25 May 2005 14:18:31 -0700 (PDT) > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > >Tom Jennings wrote: >> For neon, from flawed memory, strike-over is around 100V, and >> sustain around 80V. [...] You could probably make a coincident-voltage >> memory from them... but they'd be slow I think, but pretty. > >Sounds like a fun project! > >Lessee... If the numbers are 80V and 100V... > >You have an X-Y matrix. Steady state, you apply +7.5V to each X line, >and +97.5V to each Y line, so each tube has 90V across it. > >You turn on a particular tube by dropping the X line to 0V and raising >the Y line to +105V. The selected tube sees 105V, while the other tubes >in the same row and column see 97.5V. > >I'm guessing that if you measure the current in those lines, you can >tell when it strikes, or maybe you just wait long enough before dropping >the lines back to the steady state. > >To turn off a particular tube, you raise the X line to 15V and drop >the Y line to 90V. Now there's only 75V across the selected tube, >while other tubes in the same row and column will still have 75V. >Again, there should be a current drop when the selected tube turns >off. > >And you read a tube either by trying to turn it on, or trying to turn >it off. If the current doesn't change enough, it hasn't flipped. > >The voltages will need to be controlled fairly well, since the >margins are narrow. > >Will neon bulbs have reduced lifetime if you run them on DC? > >Eric The numbers for the common NE2 were more like 65 and 90V and are also sensitive to light! Neons for logic were burned in for consistant threshold and extinguish voltages. Oh, and they are relatively slow. Other uses for Neons is they behave above the stike voltage like a zener diode so it's not uncommon to tsee them used as a 90V offset or reference. Allison

19 years, 1 month

Neon bulb logic elements link?

by pete＠dunnington.u-net.com

On May 25 2005, 9:01, Stan Barr wrote: > Hi, > > Pete Turnbul said: > > > On May 24 2005, 17:11, James Fogg wrote: > > > > > I seem to recall that neon's behave as diodes. I might be wrong. > > > > No, neons happily pass AC. You must be thinking of something else. > > They have hysteresis. The striking voltage is higher than the > maintaining voltage which allows you to use them as switches and > oscillators. I know. The first oscillator I ever built was a relaxation oscillator using a neon lamp. -- Pete Peter Turnbull Network Manager University of York

19 years, 1 month

Neon bulb logic elements link?

by herby1620＠yahoo.com

Still more stories about Neon lamps: Experimenting as a kid (35 years ago or so), I hooked one (an NE-2) directly across a telephone line as an indicator for the ring signal. It worked "kinda". Turns out that the AC voltage of the ring caused the bulb to strike, and since I didn't have a resistor in series, the current of the strike was enough to signal "answer". Then the central office returned the supply voltage to the normal 48 volts, and since this was below the keep voltage, the bulb went out and with no current, the C.O. thought the phone was hung up. The other extension phones had a short ring. The caller heard little. You had to run to the phone and answer it if you wanted to talk. It makes for a very annoying trick! The solution to this is to add a resistor (about 51k as I remember it) in series. The current drawn when ringing thru the resistor isn't enough to make the C.O. trip answer. Now fast forward a bunch of years, and I work for a company that uses neon-CdS "optical isolators" to detect ring. They DID put the reisitor in series. The problem then happened that they forgot to put a capicator in series as well. Normally this doesn't make any difference, but in some areas (mostly rural) the voltage is raised to make up for long line loss. Sometimes it is raised to over 90 volts. In some of these situations the indicator would always indicate "ring". It wasn't too good. Now days we use optical isolators and a series R-C combination. It works pretty well. You need a reverse diode across the optical isolator (an LED works well, and makes a good indicator) so the cap won't take on a DC bias. p.s. 4 layer diodes work like neon lights (different strike/hold voltages) but a lower voltages. An X-Y matrix similar to the neon ones discussed would work, but with no visual readout. These were proposed, but IC's came into being, and the hassel wasn't worth it. Oh, well. __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

19 years, 1 month

AT&T Safari laptop

by aw288＠osfn.org

I was given an old Safari laptop, but no power supply. Does antone know what kind of voltage this thing wants? William DOnzelli aw288 at osfn.org

19 years, 1 month

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test-drb May 2005