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Message Digest Volume 28 : Issue 44 : "text" Format Messages in this Issue: Re: TTY 33 and 35 case and cover composition? Re: TTY 33 and 35 case and cover composition? Re: 911 service not prepared for new generation of pranksters Re: Surge Protection Re: More articles on illicit cell phone picture transmission Re: TTY 33 and 35 case and cover composition? Pat Townson has a new mailing address ====== 27 years of TELECOM Digest -- Founded August 21, 1981 ====== Telecom and VOIP (Voice over Internet Protocol) Digest for the Internet. All contents here are copyrighted by Patrick Townson and the individual writers/correspondents. Articles may be used in other journals or newsgroups, provided the writer's name and the Digest are included in the fair use quote. By using -any name or email address- included herein for -any- reason other than responding to an article herein, you agree to pay a hundred dollars to the recipients of the email. =========================== Addresses herein are not to be added to any mailing list, nor to be sold or given away without explicit written consent. Chain letters, viruses, porn, spam, and miscellaneous junk are definitely unwelcome. We must fight spam for the same reason we fight crime: not because we are naive enough to believe that we will ever stamp it out, but because we do not want the kind of world that results when no one stands against crime. Geoffrey Welsh =========================== See the bottom of this issue for subscription and archive details and the name of our lawyer, and other stuff of interest. ---------------------------------------------------------------------- Date: Wed, 11 Feb 2009 13:42:18 -0800 (PST) From: hancock4@bbs.cpcn.com To: redacted@invalid.telecom.csail.mit.edu Subject: Re: TTY 33 and 35 case and cover composition? Message-ID: <5589ed82-1b85-430f-89e2-a4c60bf71c97@w35g2000yqm.googlegroups.com> On Feb 11, 3:51 pm, hanco...@bbs.cpcn.com wrote: > ***** Moderator's Note ***** > Many schools _DID_ use the Model 33 as a terminal during the start of > the computer revolution, and that gave the 33 an undeserved reputation > for unreliability. The 33s used in my high school and the central computer center had continuous use during school hours but as I recall very reliable. I also recall that they had an excellent reputation. By the 1970s mini- computer makers sold the 33 as an I/O interface and I think they were extremely common in that service. Originally they rented the machine from the phone company (about $100/ month), that machine had the built-in dial, speaker, and modem and push button control panel on the right side. (We had to get used to an all-number dial, in those days all our phone numbers were still 2L-5N). The phoneco provided service. Later, they purchased a fleet of machines and hired a technician to service them. Instead of the built-in modem these had either an acoustical coupler or interface to a separate modem. Instead of paying $$$ to a commercial time sharing service they bought their own computer (HP-2000) >Computer users, especially children in computer labs, > placed much higher demands on the machines than they were designed to > serve. But the machines seemed to work well. Except in the case of one kid, who had a habit of eating raisins while he was on the machine. Service was needed and the repairman (from Bell at that time), came out and dug out a large pile of raisins from the inside. A large component required replacement. He told the teacher that the company would cover the repair cost this time but not in the future. As an aside, one rich kid rented his own Teletype for a month or so. A $100 back then would be about $500-$600 today. That kid turned into an early hacker, and today is a big shot security consultant. The Western Union Technical Journal archives of this newsgroup, contains an article on the introduction of ASCII and the new model 33. (The model 32 was designed for Baudot use). See: http://massis.lcs.mit.edu/telecom-archives/archives/technical/western-union-tech-review/18-1/p018.htm Clearly the 33 was designed for computer use as well as telegraphy and I suggest the designers did an excellent job especially given the very limited computer time sharing capability when they began their task. The amazing thing here we all are, 45 years later, using pretty much the protocols developed way back then. Newspaper articles in that time frame envisioned all this; that some day homes would have a terminal and connecting to supermainframes. see: http://massis.lcs.mit.edu/telecom-archives/archives/technical/western-union-tech-review/18-2/p050.htm ------------------------------ Date: Wed, 11 Feb 2009 22:53:48 -0500 From: "Dr. Barry L. Ornitz" <BLOrnitz84@charter.net> To: redacted@invalid.telecom.csail.mit.edu Subject: Re: TTY 33 and 35 case and cover composition? Message-ID: <d3Nkl.21215$Tt1.2761@newsfe07.iad> <hancock4@bbs.cpcn.com> wrote in message news:2b9d832c-9a05-4bc9-ba4b-f202085b4288@x9g2000yqk.googlegroups.com... > How does one differentiate between actual Bakelite and plain plastic? Bakelite is phenol-formaldehyde and it is a thermosetting plastic, i.e. it does not melt. Another test is to touch a hot soldering iron to an unobtrusive area on the inside of the part. Bakelite will not melt but it will char releasing a very distinctive phenol odor like a burned out resistor. :-( > ***** Moderator's Note ***** > > The Model 33 case was plastic, not Bakelite, which was too prone to > chipping and cracking to be used in a high-vibration environment > such as a Teletype machine. Earlier machines, such as the venerable > Model 15, had metal cabinets. > > Bill Horne > Temporary Moderator Ham radio operators who first used radio teletype systems usually used military surplus Model 15 and Model 19 machines from WWII. Later, Model 28 machines were used too. These were all Baudot 5-bit machines. All capital letters were used, and to get more than the 32 possible characters, two keys were dedicated to FIGS and LTRS. To type a number for example, you first pressed the FIGS key and then the key with the number on it. Then you pressed the LTRS key to go back to typing letters. Often operators would forget and garbage was printed leading to modifications like "unshift on space." At the end of a line, you pressed the return key, then usually a few LTRS keys to allow for the physical time for the print mechanism to return to the beginning of a line. Then you pressed a key for a new line (LINE FEED) unless you wanted to print over the line you just printed. Again this was often forgotten. The Model 33 was an eight bit ASCII machine. The old Baudot machines were asynchronous machines with a start and stop bit; sometimes the stop bit was one and a half times the length of the other bits. Different speeds were used, but amateur radio operators settled on the 60 speed (45.5 baud with a 22 millisecond bit). Bill is quite correct about the weight of these old behemoths. The military Model 15 came on a HEAVYweight stand with cast iron legs. The Model 19 came with a table that seemed to weigh a ton! While in graduate school at Clemson back in the early 1970's, a math professor friend was donated a Model 19 and table. The only problem was getting it from Ft. Jackson in Columbia, SC, back to the professor's home in Clemson. The three of us had an old beat-up pickup, so off we went to Columbia. We found it easy enough. It was waiting on a loading dock - covered in Cosmoline and dirt. Some kind Sergeant was nearby and he got several recruits to load it on our truck. We tied it down to keep it from moving, a real waste of effort as that beast was so heavy it couldn't move. The truck was so weighted down that its suspension nearly bottomed out and we felt every pothole. We got back to Clemson, and tried to get it out of the truck. After much effort, the three of us and the professor got it off the truck and to his back door. THEN HE TOLD US IT NEEDED TO BE CARRIED UP THE STAIRS TO WHERE HIS HAM SHACK WAS LOCATED! So we called in more help and three more club members arrived. It took the seven of us about five hours to remove the Teletype from the table, dismantle the table, clean off the grease, lug it up the stairs piece by piece, and reassemble everything. This "junque" used metal so thick that it could take a direct hit with an M-1 and still keep clanking away. Hams refer to old vacuum tube radios and other military surplus as "Boatanchors," and believe me, the Model 19 was one. The Wiki page on teleprinters has a partial history and some good technical information at http://en.wikipedia.org/wiki/Teleprinter. A booklet, "The Teletype Story," with lots of pictures may be found at http://www.kekatos.com/teletype/The_Teletype_Story_50th_Anniversary.htm. Now, nearly forty years later, I can remember the fun we had with these military surplus machines, but I can also remember the pain and soreness that resulted from our crew of seven stooges trying to carry a Model 19 up those stairs! By the way, I had a Kleinschmidt teleprinter, the lightweight unit. 73 (Morse code abbreviation for Best Regards), Dr. Barry L. Ornitz WA4VZQ BLOrnitz84@charter.net [transpose digits to reply] ------------------------------ Date: Wed, 11 Feb 2009 20:00:41 -0500 From: T <kd1s.nospam@cox.nospam.net> To: redacted@invalid.telecom.csail.mit.edu Subject: Re: 911 service not prepared for new generation of pranksters Message-ID: <MPG.23fd3ec2c1dbb5e99898e9@reader.motzarella.org> In article <IOmkl.20113$Ws1.5239@nlpi064.nbdc.sbc.com>, diespammers@ikillspammers.com says... > > Not saying the police were right or wrong in this case, middle of the > night raids are needed for the safety of the police and for protection > of others. When a person who is wanted and considered dangerous the > arrest is made no matter what time it is. Say what? SWAT teams are armed to the teeth. They can go in any damn time they please, their whole thing is element of surprise. ***** Moderator's Note ***** This has veered away from E911 and VoIP, so I'm closing the thread. Bill Horne Temporary Moderator ------------------------------ Date: 11 Feb 2009 21:26:37 -0500 From: kludge@panix.com (Scott Dorsey) To: redacted@invalid.telecom.csail.mit.edu Subject: Re: Surge Protection Message-ID: <gn01ct$3km$1@panix2.panix.com> In article <edadf13a-6e38-46f7-ad83-64b88f211463@t13g2000yqc.googlegroups.com>, <4netpost@gmail.com> wrote: >I have a need to add some surge protect a telephone system. > >I need the surge protection on the incoming circuits, right at the >demark point. I have several lines including POTS voice lines, POTS >dial in modem lines, VDSL, ADSL, and T1 circuits. Is there a surge >protector that will protect all of the above lines without degrading >performance? Yes. The telco should provide it already. If they do not, Citel will sell you a number of gas tube/MOV systems. As always, the quality of the system depends entirely on the quality of your ground. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." ------------------------------ Date: Thu, 12 Feb 2009 09:57:20 -0500 From: "MC" <for.address.look@www.ai.uga.edu.slash.mc> To: redacted@invalid.telecom.csail.mit.edu Subject: Re: More articles on illicit cell phone picture transmission Message-ID: <iJWkl.2947$v8.1090@bignews3.bellsouth.net> <hancock4@bbs.cpcn.com> wrote in message news:06349e04-3e6a-42ef-bdc4-c03195593477@t3g2000yqa.googlegroups.com... > "No doubt there's truth in that. But to me, the more urgent problem is > that kids and even twenty-somethings don't realize how this could > impact their lives years down the road. Well, kids better start > thinking - whether they're shooting a video, posing for a picture, or > sending an e-mail. Sure, too many young people are making stupid, > shortsighted decisions. But that's nothing new. What's new are the > places they'll go and the people they'll see once they hit the "send" > key... Bingo! That is far more important than the immediate legal issues. We seem to have a new generation of people who have completely fallen into the "small circle of friends illusion" ("everything I send out will only be seen by a small circle of friends"). This was a common problem in the early days of Usenet (remember postings like "don't tell my boss about my cocaine habit?") but I thought people had grown up a bit. ***** Moderator's Note ***** Felix Dzerzinski, the founder of the KGB, was reported to have said "Never reveal to a friend anything you would conceal from an enemy". Bill Horne Temporary Moderator ------------------------------ Date: Thu, 12 Feb 2009 10:02:33 -0500 From: "MC" <for.address.look@www.ai.uga.edu.slash.mc> To: redacted@invalid.telecom.csail.mit.edu Subject: Re: TTY 33 and 35 case and cover composition? Message-ID: <aOWkl.2950$v8.2747@bignews3.bellsouth.net> <hancock4@bbs.cpcn.com> wrote in message news:2b9d832c-9a05-4bc9-ba4b-f202085b4288@x9g2000yqk.googlegroups.com... > How does one differentiate between actual Bakelite and plain plastic? Bakelite is hard, dense, and brittle, smooth on the surface but (as I recall) somewhat crumbly inside if broken. I have never seen any that wasn't dark colored. The plastic covers of the Model 33 Teletypes that I remember are uniformly gray and smooth-textured and would probably snap rather than crumble if broken. On eBay, the antique dealers tend to say "Bakelite" for any plastic object more than five years old. Or so it seems! They don't know what they're talking about. They also say "Cold War Era" for any artifact from 1930 to 1995. And then there are people who think "the fifties" spans the whole twentieth century :) ------------------------------ Date: Thu, 12 Feb 2009 13:32:13 -0500 From: Telecom digest moderator <redacted@invalid.telecom.csail.mit.edu> To: redacted@invalid.telecom.csail.mit.edu Subject: Pat Townson has a new mailing address Message-ID: <20090212183213.GC16813@telecom.csail.mit.edu> I spoke with Pat Townson today: he says they're feeding him well, but he misses his old cell phone. The staff at his nursing home gave me a new address for snail mail: they said they've been having problems with things sent to Mulberry St. Regal Estate Nursing Home P.O. Box 627 Independence, KS 67301 (620) 331-8789 Pat has a phone in his room now: you can call him directly at 620-331-2028. Bill Horne Temporary Moderator ------------------------------ TELECOM Digest is an electronic journal devoted mostly to telecom- munications topics. It is circulated anywhere there is email, in addition to Usenet, where it appears as the moderated newsgroup 'comp.dcom.telecom'. TELECOM Digest is a not-for-profit, mostly non-commercial educational service offered to the Internet by Patrick Townson. All the contents of the Digest are compilation-copyrighted. You may reprint articles in some other media on an occasional basis, but please attribute my work and that of the original author. The Telecom Digest is currently being moderated by Bill Horne while Pat Townson recovers from a stroke. Contact information: Bill Horne Telecom Digest 43 Deerfield Road Sharon MA 02067-2301 781-784-7287 bill at horne dot net Subscribe: telecom-request@telecom-digest.org?body=subscribe telecom Unsubscribe: mailto:telecom-request@telecom-digest.org?body=unsubscribe telecom This Digest is the oldest continuing e-journal about telecomm- unications on the Internet, having been founded in August, 1981 and published continuously since then. 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Please make at least a single donation to cover the cost of processing your name to the mailing list. All opinions expressed herein are deemed to be those of the author. Any organizations listed are for identification purposes only and messages should not be considered any official expression by the organization. End of The Telecom digest (7 messages) ******************************