Yes, IMHO the ASR33 reader is an interesting thing to have, but it's only 10cps, and it is not kind to the tapes. A good capstan-fed optical paper tape reader will do between 300 and 1000cps [1] and will not damage the tapes. Well worth trying to track one down as well as the Teletype [1] I have a soft spot for Trend paper tape readers. I have several HSR500s (bidirectional, 500cps) and UDR700s (unidirectional, 700 cps). The nice thing about them is that the automatically set the read threshold level, they can thus work with partically transparent tape, are unaffected by changed in the lamp brightness and are a doddle to set up. -tony

How heavy are these things? They look like solid steel in pictures. That's one of the things that presents a big problem for me up here in Canada... shipping from the US has gotten outrageously expensive. -----Original Message----- From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of tony duell Sent: Wednesday, October 14, 2015 5:40 AM To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Subject: RE: Fair price and ways to find a teletype [ASR33] are working on it to bring it back. A general point. The 'Typing Unit' -- that is the main chassis with the motor, carriage, platen, punch, in fact everything apart from the keyboard, tape reader and electronic unit is not normally bolted down. It rests on rubber mounts. If you are shipping an Model 33, you must either put in a shipping screw, or preferably remove the typing unit (it's just some electrical connections and the H-plate link to the keyboard trip linkage) and pack it separately. Otherwise you will have damage. If it;s a real Teletype as opposed to, say a Data Dynamics 390 (which is Teletype mechanicals in a Data Dynamics case) then note that the plastic cover is likely to have gone very brittle with age. Take care. clever you will not get it without some help. All I can say is YMMV (and mine certainly did). I rebuilt my first Model 33 when I was still at what you would call high school. Back then there was no WWW, no places to get manuals, no lists like this one. And I didn't have the paper manuals. I took the whole thing apart down to the last nut and bolt. And got it running. You need a good hand tool kit, but not that much more unless you need to make parts. Perhaps because I had a mis-spent childhood but I had no problems figuring out how it all works. It's not that complicated, it follows very logical principles. That I will agree with. My first one, working without manuals, took about 6 weeks of tinkering in the evenings after school and at weekends to get going. And it certainly didn't work first time (it almost did, I had misunderstood the print suppression linkage). -tony = ----- No virus found in this message. Checked by AVG - www.avg.com Version: 2015.0.6172 / Virus Database: 4447/10805 - Release Date: 10/12/15

On 10/14/2015 12:48 PM, Brad wrote: Well for big things shipping I think it is about the same for the last few years. It is the US mail that is strange ... $3.00* for 3 weeks or $60 for overnight. I expect still cheaper shipping than when new. Note you still need a truck to get from the shippers warehouse. Ben. * I think books still send that way.

Brad, A few montns ago, with a fair bit of help of the folks on this list, I did up an Altair 8800 rebuild. And apparently you & I both saw the same videos, as I got all hot and bothered about getting an ASR33 and using it to load software - BASIC, for starters - into the Altair. And again, on members' suggestion, I joined the Greenkeys list. Too bad, but I was totally +shocked+ at the 'value' placed on ASR33 these days!! Thousand dollars and more, not all all unusual.. and my resources just can't justify that level of expenditure for what is generally a 'cheap' DIY hobby of sorts. Meanwhile, a Greenkeys member in St. Louis, MO popped up with a very nice M15 (ex-Bell) that was Free to Good Home. I have (or at least had, ha!) a good friend in St. Louis, and he was able to take care of the pickup for me - and several months later, i arranged to have it delivered to my house by a relative. Now the M15 isn't a 33ASR, and lacks the paper tape punch & reader (though devices do exist). But what it is, is a truly fantastic piece of electro-mechanical engineering that borders on the "tight metal" genre of some earlier business machines, such as the Felt & Tarrant Comptometer. If you have general mechanical experience, I'd say the M15 is roughly on a par with a 2-spd or even 3-spd automatic transmission, in terms of mechanical complexity (the the tranny will have a higher parts count.. I think!). So while they can be worked with, and documentation is plentiful, they are a bit intimidating the first time you see one in action - or inaction, as it may be - and they do NOT respond kindly to false moves or other ham-fistery. But they are well worth learning, and don't yet seem to have joined their later progeny in the financial stratosphere. -Bill On Wed, Oct 14, 2015 at 2:39 PM, william degnan <billdegnan at gmail.com> wrote:

On Thursday (10/15/2015 at 05:57PM +0100), Dave Wade wrote: Altair 680 (M6800 based) had one version of the PROM that worked with 5-level BAUDOT teletypes and the more common version that worked with 7-level ASCII teletypes such as the M33. -- Chris Elmquist N?JCF

So you've shipped these before? What sort of cost is typical around the US? My problem is just finding one at this point. Also separate question to others: I want to stay away from the Baudot machines, right? (ie. Model 28, etc) -----Original Message----- From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of william degnan Sent: Wednesday, October 14, 2015 12:39 PM To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Subject: Re: Fair price and ways to find a teletype You can ship these in a box if you detach the pedestal and put it on its side, making sure the main unit is well padded and there is a weight balance to the box, as you never know from what angle the box will sit/fall/land/be carried. I shrink wrap the main TTY to ensure it stays secure, then wrap in layers of bubble wrap and foam. I have shipped five or six that way. You can also use two boxes. It's very easy to re-attach the main unit from the pedestal, many have a reader motor in the pedestal, but you just unscrew it. On Wed, Oct 14, 2015 at 3:28 PM, ben <bfranchuk at jetnet.ab.ca> wrote: -- Bill ----- No virus found in this message. Checked by AVG - www.avg.com Version: 2015.0.6172 / Virus Database: 4447/10805 - Release Date: 10/12/15

On 2015-Oct-15, at 6:25 PM, Brad wrote: I'd say it largely depends on what your interests or purposes are. A brief overview of the technology: In the main, there were 3 generations of teletypes: Era Common Model Code Speed Common Interface Mechanism ====== ============ ========== ======= =============== ============ 1) 1930s-40s: Model 15,19 5-level ~30-50 bps 60mA current loop Modified Typewriter Cage 2) 1950s-60s: Model 28 5-level <=75 bps 60mA current loop Typebox 3) 1960s-70s: Model 33 7/8-level/ASCII 110 bps 20mA current loop Type Cylinder These are the "page printers" that would type across and down sheet paper fed from a roll. There are other models, variations on the above. Not included here are the tape printers, simpler mechanisms that printed in one dimension on a narrow paper tape, ala stock tickers. The mechanism was the overriding distinction between these generations as speed and code capability followed from the mechanism: 1) Modified Typewriter Cage: Decoding bars select 1-of-30-odd symbol/type arms arrayed in an arc, to swing and hit the paper, just like a common typewriter. 2) Typebox: An ~ 1" by 2" metal box holds typeface symbol pins in two 4*8 matrices. The box is shifted up/down and left/right to bring a selected symbol pin between a hammer and the paper. 3) Type Cylinder: A cylinder embossed with the typeface is moved up/down and rotated CW/CCW to select a symbol. The 5-level devices are commonly referred to as Baudot devices but this is not strictly correct as they generally use the ITA2/USTTY codes (International Telegraphy Alphabet No.2). The speed of Model 28s (at least) was determined by a selected gear-set. 5-level machines need code conversion of course. They all need current loop interfaces. A lot of old computer equipment will do 110 bps as the 33s were so associated with computers. For working form modern equipment, the bit rates for all of them are potentially awkward. When working on the 28s, which were geared for 75 bps, I lucked out as I found the USB-serial interface I was using could do 75 bps - not entirely surprising as 75 is a factor of 2 down in the common 9600,1200,300 bps series. How many USB-serial interfaces are capable of this I have no idea. Regardless, the baud rates are slow enough that bit-banging from a program is not difficult, or an adjustable RC oscillator to a UART should do.

On 2015-Oct-15, at 10:19 PM, Chuck Guzis wrote: Sure, if you can hack the hardware or have low-level access to the device you can typically set the interval-counter base in accordance with it's capabilities (time resolution). But working from OSX unix system-call level to a plastic-encapsulated USB-serial dongle, I was pleasantly surprised that "75" was accepted by the IO/device driver. IIRC, it didn't accept 110 or other values outside the divide-by-2 sequence, and 75 was the final. So it wasn't a general frequency-to-period calculation from a high-res timer. Maybe it was a factor-of-two calculation that hit the counter resolution limit at 75, or the driver writer actually included 75 in a table lookup.

Thanks for this great explanation. So would anyone doing computing back in the early 70s have used a 5 level machine? I saw this one on ebay (or is it two? Not sure what the deal is here) It's probably sacked: http://www.ebay.com/itm/Teletype-equipment-1-model-28-writer-1-reperforater- 1-50vdc-supply-etc-/121784463105?hash=item1c5aeb6f01:g:UR8AAOSwnDZUJHWs -----Original Message----- From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Brent Hilpert Sent: Thursday, October 15, 2015 10:07 PM To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Subject: Re: Fair price and ways to find a teletype On 2015-Oct-15, at 6:25 PM, Brad wrote: machines, right? (ie. Model 28, etc) I'd say it largely depends on what your interests or purposes are. A brief overview of the technology: In the main, there were 3 generations of teletypes: Era Common Model Code Speed Common Interface Mechanism ====== ============ ========== ======= =============== ============ 1) 1930s-40s: Model 15,19 5-level ~30-50 bps 60mA current loop Modified Typewriter Cage 2) 1950s-60s: Model 28 5-level <=75 bps 60mA current loop Typebox 3) 1960s-70s: Model 33 7/8-level/ASCII 110 bps 20mA current loop Type Cylinder These are the "page printers" that would type across and down sheet paper fed from a roll. There are other models, variations on the above. Not included here are the tape printers, simpler mechanisms that printed in one dimension on a narrow paper tape, ala stock tickers. The mechanism was the overriding distinction between these generations as speed and code capability followed from the mechanism: 1) Modified Typewriter Cage: Decoding bars select 1-of-30-odd symbol/type arms arrayed in an arc, to swing and hit the paper, just like a common typewriter. 2) Typebox: An ~ 1" by 2" metal box holds typeface symbol pins in two 4*8 matrices. The box is shifted up/down and left/right to bring a selected symbol pin between a hammer and the paper. 3) Type Cylinder: A cylinder embossed with the typeface is moved up/down and rotated CW/CCW to select a symbol. The 5-level devices are commonly referred to as Baudot devices but this is not strictly correct as they generally use the ITA2/USTTY codes (International Telegraphy Alphabet No.2). The speed of Model 28s (at least) was determined by a selected gear-set. 5-level machines need code conversion of course. They all need current loop interfaces. A lot of old computer equipment will do 110 bps as the 33s were so associated with computers. For working form modern equipment, the bit rates for all of them are potentially awkward. When working on the 28s, which were geared for 75 bps, I lucked out as I found the USB-serial interface I was using could do 75 bps - not entirely surprising as 75 is a factor of 2 down in the common 9600,1200,300 bps series. How many USB-serial interfaces are capable of this I have no idea. Regardless, the baud rates are slow enough that bit-banging from a program is not difficult, or an adjustable RC oscillator to a UART should do. ----- No virus found in this message. Checked by AVG - www.avg.com Version: 2015.0.6172 / Virus Database: 4447/10805 - Release Date: 10/12/15

On 2015-Oct-15, at 11:20 PM, Brad wrote: As others mentioned, there was some use of 5-level machines with hobbyist computers in the 70s. 5-level machines were available as surplus in the 70s and the idea was that they could be an inexpensive terminal or hard-copy printer. So in the era of the first generation of PCs - the hobbyist era, Altair, SWTP 6800, etc. - there was some degree of effort to interface to 5-level machines. In practice I believe the use was pretty limited. It faded away pretty quickly, in part because the 5-level machines have a small character set - inadequate for 70s programming languages and apps. BTW: "-level" is just the term used in the teletype world for the number of bits in the character code. Presumably it's use in the teletype world predates the term bit for binary digit, or binary association. Well, there is a model 28 there. + inside, as much as one can see in the pic, the mechanism looks pretty good. - missing a key - looks like a pretty worn keyboard shroud - horrible paint job of the case exterior. The 'reperforator' looks like it could be this: http://www.baudot.net/teletype/M28-X.htm#M28-KTR Not directly familiar with the model but it sounds like it does keyboard-to-loop and loop-to-punch-tape-with-print Seems like a pretty steep price for the condition, esp. after shipping.

On 2015-Oct-14, at 11:52 AM, Brad wrote: Vancouver region: Two years ago Rob and I got two 28s at the radio museum going as well as a 33. Getting the 28s functioning was in preparation for a movie shoot. The 33 was, well, it's a 33 and we're working on these things. Still have a 15 and a Lorenz (15-class knock off) to work on when I can get back to major projects. In 1976 when I was working with my dad's friend on building his IMSAI, he had a plastic-wrapped 33-ASR waiting in a corner for the computer to be ready. I suspect it was a refurbished unit, but when the plastic came off it looked as good as new. And yes, when the IMSAI was ready we proceeded to toggle in the bootstrap, load MS BASIC via the 33 paper tape reader, and type in a BASIC program. Vancouver was a smaller city back in the 70s but I think teletypes were as dense here as they were anywhere. Being somewhat remote but a major port city and center for transportation and shipping, communications was important - there may have been more teletypes here than typical. Currently, I know of two other 28s in the Vancouver region (not meaning to imply any of them are available though). The radio museum threw out a 35-ASR 15 years ago. There may have been another 1 or 2 that were discarded. Yup, hindsight is great.