[cctalk] Re: Mechanical Selectric keyboards on video terminals (was Re: Typing class in high school)
On Sat, Jan 28, 2023 at 5:34 PM Steve Malikoff via cctalk < cctalk@classiccmp.org> wrote: > There were some video terminals with mechanical Selectric keyboards, one > for example being the RCA Spectra 70/752 from the mid/late 60s. > For this RCA engineers substantially modified a Selectric 1 keyboard with > many new bespoke mechanical parts to output 7-bit ASCII directly. > The earlier RCA 6050 video data terminal and models 6051-1, 2, 3 > Interrogator used a powered ASR33 keyboard, and the main console of the IBM > Office System/6 > workstation also used a powered Selectric keyboard. > > I've been working on a project for the last few years on and off to > recreate this terminal's keyboard, starting with fixing a rusty seized > Selectric II to operating > condition then splitting the keyboard off from the power frame and > powering the filter shaft with a motor in lieu of the normal print shaft > gear train doing it. Steve, This sounds like a very cool project. I'd love to see the photos you have so far. Sellam
[cctalk] Re: Mechanical Selectric keyboards on video terminals (was Re: Typing class in high school)
On 1/28/23 17:34, Steve Malikoff via cctalk wrote: > Chuck said > I say 'some of' because in building and operating this I've realised that a > lot of the Selectric 'feel' people rave about actually comes from the print > shaft, > tilt/rotate tapes mech, shift cam, Whiffletree and typeball movement all > operating in concert (along with its sound) in a fraction of a second, the > keyboard > mech is only part of it. > How does your setup differ form the 1052 keyboard? I know that uses a modified 024 keyboard, so interposers. Under DOS/360, a user program could write a CCW string to ring the 1052 bell. If that CCW string included a TIC back to the bell-ring CCW, the bell would just keep ringing with the keyboard locked out. Fun and games, from very many years ago. --Chuck
[cctalk] Re: Mechanical Selectric keyboards on video terminals (was Re: Typing class in high school)
On 2023-01-28 11:10 p.m., Chuck Guzis via cctalk wrote: On 1/28/23 17:34, Steve Malikoff via cctalk wrote: Chuck said How does your setup differ form the 1052 keyboard? I know that uses a modified 024 keyboard, so interposers. Under DOS/360, a user program could write a CCW string to ring the 1052 bell. If that CCW string included a TIC back to the bell-ring CCW, the bell would just keep ringing with the keyboard locked out. Fun and games, from very many years ago. --Chuck The keyboard on a 1052 is a keypunch keyboard I believe it is the same as the 029. The printer in the 1052 is a keyboardless Selectric with no tab rack and they spaced via a cam on the OP shaft instead of taking a cycle. The ones I saw on a couple 360s (22 and 25) the space cam was so worn it wobbled when it took a cycle, but the customer would never let us do anything with it as long as it worked because they could not do anything with out the console. Paul.
[cctalk] Re: Mechanical Selectric keyboards on video terminals (was Re: Typing class in high school)
On 1/28/23 20:20, Paul Berger via cctalk wrote: > The keyboard on a 1052 is a keypunch keyboard I believe it is the same > as the 029. The printer in the 1052 is a keyboardless Selectric with no > tab rack and they spaced via a cam on the OP shaft instead of taking a > cycle. The ones I saw on a couple 360s (22 and 25) the space cam was so > worn it wobbled when it took a cycle, but the customer would never let > us do anything with it as long as it worked because they could not do > anything with out the console. Was the 1052 more or less durable than the model B adapted for the 1620? With its movable carriage, it always seemed to be in danger of self-destructing--the thing would shake a bit then a carriage return was executed. --Chuck
[cctalk] Re: Mechanical Selectric keyboards on video terminals (was Re: Typing class in high school)
> On 2023-01-28 11:10 p.m., Chuck Guzis via cctalk wrote: >> On 1/28/23 17:34, Steve Malikoff via cctalk wrote: >>> Chuck said >> >> How does your setup differ form the 1052 keyboard? I know that uses a >> modified 024 keyboard, so interposers. >> Under DOS/360, a user program could write a CCW string to ring the 1052 >> bell. If that CCW string included a TIC back to the bell-ring CCW, the >> bell would just keep ringing with the keyboard locked out. >> >> Fun and games, from very many years ago. >> >> --Chuck >> >> > The keyboard on a 1052 is a keypunch keyboard I believe it is the same > as the 029. No, Chuck is correct the 1052 used a modified 024 keyboard, even through you would think it would have been an 029. Marc recently did a video on a keypunch keyboard, the 1052 one looks much the same. Mine differs a lot, the Spectra 70/752 used a Selectric mechanism, totally different to the keypunch keyboard. The Selectric keyboard is designed around doing a print cycle while the electric keypunch keyboard seems to be power driven to reduce or eliminate double-keying errors as the primary motive. I think, but am not certain. Sellam asked for a few photos of my 70/752 recreation project so here are some I just took. As I said, it's still a WIP with lots to do. http://www.surfacezero.com/g503/uploads/612/RCA_Spectra_70-752_keyboard_recreation_WIP_01.jpg http://www.surfacezero.com/g503/uploads/612/RCA_Spectra_70-752_keyboard_recreation_WIP_02.jpg http://www.surfacezero.com/g503/uploads/612/RCA_Spectra_70-752_keyboard_recreation_WIP_03.jpg It's running, with the LEGO motor at the voltage indicated. The microswitch clevis rods will be cut to the right size once the storage bar is made. Also the 3D test prints of brackets, clutch and other parts etc. in the bags. All printed parts on the thing are white PETG. Note there is an added bit 7 bail interposer, spring return frame, clutch on the inside of the modified right frame, RCA-style mounting brackets, storage bar pivot rod, AC motor (needs a front bearing bracket made or I might just cut up the gearbox casing on it). Steve.
[cctalk] Re: Mechanical Selectric keyboards on video terminals (was Re: Typing class in high school)
Way back in the mid 70s, I picked up a keyboard that someone told me was from a Spectrola, but it was all electronic. EBCDIC, with a big diode matrix, George Risk sealed key switches, and a few Fairchild ICs (DTL, I think, but it's been a long time.) I don't know what it went to, but it definitely wasn't IBM. It was lost in a move... --Chuck
[cctalk] Re: Mechanical Selectric keyboards on video terminals (was Re: Typing class in high school)
> -Original Message- > From: Steve Malikoff via cctalk > Sent: 29 January 2023 01:35 > To: General Discussion: On-Topic and Off-Topic Posts > Cc: ste...@malikoff.com > Subject: [cctalk] Mechanical Selectric keyboards on video terminals (was Re: > Typing class in high school) > > Chuck said > > Speaking of keyboards, were there any computer keyboards or typewriter > > keyboards with interposer mechanisms such as used on IBM keypunches? > > I recall that was one thing that had a very different "feel" from a > > typewriter keyboard. It changed my keyboarding style. Welll whilst I didn't know this until yesterday, the IBM 2260 VDU had such a keyboard. There is one for sale on E-Bay https://www.ebay.com/itm/115685064067 and there are nice pictures of the keyboard. Dave
[cctalk] Re: Mechanical Selectric keyboards on video terminals (was Re: Typing class in high school)
On 2023-01-29 12:25 a.m., Chuck Guzis via cctalk wrote: On 1/28/23 20:20, Paul Berger via cctalk wrote: The keyboard on a 1052 is a keypunch keyboard I believe it is the same as the 029. The printer in the 1052 is a keyboardless Selectric with no tab rack and they spaced via a cam on the OP shaft instead of taking a cycle. The ones I saw on a couple 360s (22 and 25) the space cam was so worn it wobbled when it took a cycle, but the customer would never let us do anything with it as long as it worked because they could not do anything with out the console. Was the 1052 more or less durable than the model B adapted for the 1620? With its movable carriage, it always seemed to be in danger of self-destructing--the thing would shake a bit then a carriage return was executed. --Chuck My experience is that they where pretty durable, I never saw a lot of 1052s by the time I started in 1979 there was not a lot of 360s in our branch. I think they did pretty good given that they are the same mechanism as the OP selectric the only thing different in the printer of the 1052 and also the early selectric terminals, was the 1052 and terminals had a capacitor start motor that was stronger than motor in the OP selectric, strong enough that if the mechanism did jam it could tear the teeth off of the motor belt. A 1052 would hammer away pretty constantly printing out the console log, and since it did not have a tab rack, it used spaces to line up the columns on the printout, which is likely why the space clutch and cam where in such bad shape. I don't know how they would compare to a model B that was used as an I/O I never saw any systems that used one. I would imagine that moving the heavy carriage back on something that is printing steady would be a trouble spot. I would image that kind of use would also be hard on the power roll that drives the type hammers into the paper. I don't image they would be very fast, a Selectric could print at 15.5 characters per second and at that speed the cycle clutch never latched it was just one continuous cycle. Selectric I/Os that ran at full 15.5 chars/sec suffered way more problems than ones that printed at a lower speed. IBM later came out with a second Selectric I/O which had the high wear parts beefed up in them and the keyboard was separated from the printer. All of the open transfer contacts where replaced by reed switches and magnets. The filter shaft was driven by a clutched gear running off the OP shaft and magnets against the bails under the keyboard moved magnets to select the character code but I don't recall how it was strobed, but I seem to recall that it was another magnet that was always moved by the filter shaft but was a little behind the magnets for the character reeds. These I/O II units where a lot more robust. Paul.
[cctalk] Re: Mechanical Selectric keyboards on video terminals (was Re: Typing class in high school)
Paul Berger wrote: > On 2023-01-29 12:25 a.m., Chuck Guzis via cctalk wrote: > > On 1/28/23 20:20, Paul Berger via cctalk wrote: > > > > [snip] > > believe it is the same > > as the 029. The printer in the 1052 is a keyboardless Selectric with no > > tab rack and they spaced via a cam on the OP shaft instead of taking a > > cycle. The ones I saw on a couple 360s (22 and 25) the space cam was so > > worn it wobbled when it took a cycle, but the customer would never let > > us do anything with it as long as it worked because they could not do > > anything with out the console. Was the 1052 more or less durable than the > > model B > > adapted for the 1620? > >With its movable carriage, it always seemed to be in danger of > > self-destructing--the thing would shake a bit then a carriage return was > > executed. > > > > --Chuck > > My experience is that they where pretty durable, I never saw a lot of > 1052s by the time I started in 1979 there was not a lot of 360s in our > branch. [snip] > > I don't know how they would compare to a model B that was used as an I/O > I never saw any systems that used one. I would imagine that moving the > heavy carriage back on something that is printing steady would be a > trouble spot. I would image that kind of use would also be hard on the > power roll that drives the type hammers into the paper. I don't image > they would be very fast, a Selectric could print at 15.5 characters per > second and at that speed the cycle clutch never latched it was just one > continuous cycle. Selectric I/Os that ran at full 15.5 chars/sec > suffered way more problems than ones that printed at a lower speed. The IBM Model B electric typewriter was used as a printer and keyboard entry device on at least the Bendix G-15 (mid 1950s) and the IBM 1620 Model 1 (1959). On the G-15 it ran at about 8cps (timing was determined by the drum rotation). On the 1620-1 it ran at 10cps. And yeah, they probably took quite a beating, since many sites did not have a line printer. The 1620 Model 2 (1962) used a Model 731 Selectric and drove it at 15.5cps. Paul K
[cctalk] Re: Mechanical Selectric keyboards on video terminals (was Re: Typing class in high school)
On Mon, Jan 30, 2023 at 1:59 PM paul.kimpel--- via cctalk < cctalk@classiccmp.org> wrote: > > The IBM Model B electric typewriter was used as a printer and keyboard > entry device on at least the Bendix G-15 (mid 1950s) and the IBM 1620 Model > 1 (1959). On the G-15 it ran at about 8cps (timing was determined by the > drum rotation). On the 1620-1 it ran at 10cps. And yeah, they probably took > quite a beating, since many sites did not have a line printer. > And the PDP-1. Sellam
[cctalk] Re: Mechanical Selectric keyboards on video terminals (was Re: Typing class in high school)
On 1/30/23 14:11, Sellam Abraham via cctalk wrote: > > And the PDP-1. ...and let's not forget Gog! (1954) https://i.imgur.com/j8VsH0s.png That same flick shows a Bendix cmputer https://i.imgur.com/8ezAtKr.png Don't know what model, however--awfully early for Bendix. --Chuck
[cctalk] Re: Mechanical Selectric keyboards on video terminals (was Re: Typing class in high school)
On 1/30/2023 14:38, Chuck Guzis via cctalk wrote: On 1/30/23 14:11, Sellam Abraham via cctalk wrote: And the PDP-1. ...and let's not forget Gog! (1954) https://i.imgur.com/j8VsH0s.png That same flick shows a Bendix cmputer https://i.imgur.com/8ezAtKr.png Don't know what model, however--awfully early for Bendix. --Chuck That Bendix box in the lower-right of the picture looks more like a power supply or power regulator if it's anything other than some junk thrown together by the prop department. Harry Huskey designed the G-15 in 1952-53, but the G-15A wasn't delivered to customers until 1956 and the better-known G-16D in 1957. Bendix also made avionics, however, and a standalone electronic differential analyzer, the D-12, that was available by at least 1953: http://ed-thelen.org/comp-hist/BRL2nd/B.pdf http://www.bitsavers.org/pdf/bendix/d-12/D-12_Description_Mar54.pdf The table, typewriter, and plotter shown in the ed-thelen.org link above look a lot like the ones in the first frame above from Gog. Bendix also had a later DDA, the DA-1, that attached to the G-15 and used some of the lines on the G-15's drum for intermediate storage.
