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atod
December 31st, 2010, 12:49 AM
Hi Folks

I'm going to ask this here, since the Selectric 2/3 seemed to be around during CP/M days. I saw an article in 1980 Infoworld about a product called ESCON by IPEX International. This black box claims to allow an IBM Selectric to be interface to a computer (serial?) port.

Does anyone know how it works? I think the Selectric's are nostalgic and was hoping on interfacing one up as a line printer.

Thanks,
Nick

mbbrutman
December 31st, 2010, 05:27 AM
A Selectric is a purely electro-mechanical device. (Most of them - there are some oddball models.) It has an electric motor, spinning shafts, cams levers, etc. There isn't a single transistor to be found.

To interface a Selectric to a computer you have to use solenoids to activate the keys. Instead of a nice electronic interface directly to the typewriter, you wind up building a simulation of somebody typing.

Check out some of the Selectric sites out there - I know I've read about a few conversions.

Chuck(G)
December 31st, 2010, 09:31 AM
Your best and most reliable bet would be to find a real I/O Selectric, rather than try to retrofit a typewriter with solenoids. The mechanism between the two is different in many respects and the I/O Selectric is more likely to stand up under the load a printer is likely to encounter.

Here's an IBM manual on one (http://media.ibm1130.org/E0033.pdf).

FWIW, you can probably interface any electric typewriter with sufficient effort as this site shows (http://upnotnorth.net/projects/typewriter/).

dave_m
December 31st, 2010, 10:36 AM
Your best and most reliable bet would be to find a real I/O Selectric, rather than try to retrofit a typewriter with solenoids. The mechanism between the two is different in many respects and the I/O Selectric is more likely to stand up under the load a printer is likely to encounter.

Here's an IBM manual on one (http://media.ibm1130.org/E0033.pdf).



I looked at this manual thinking to find the electrical interface and connector info, but instead found a whole world of mechanical invention. This machine would be a Rube Goldberg of delight for the mechanically inclined in the crowd.

atod
December 31st, 2010, 11:09 AM
Thanks. Here a link the a pic of the Ad. There must be some internal modification to the typewriter like you indicate.

http://img708.imageshack.us/img708/152/screenshot20101231at307.png
http://img708.imageshack.us/img708/152/screenshot20101231at307.png

dave_m
December 31st, 2010, 11:12 AM
Check out some of the Selectric sites out there - I know I've read about a few conversions.

Here's an odd mod:

http://www.youtube.com/watch?v=4_WfQoKRlxE&NR=1

atod
December 31st, 2010, 11:35 AM
Here's an odd mod:

http://www.youtube.com/watch?v=4_WfQoKRlxE&NR=1


This video is awesome!! I wonder what went into that mechanical interface

Chuck(G)
December 31st, 2010, 11:45 AM
Here's an odd mod:

http://www.youtube.com/watch?v=4_WfQoKRlxE&NR=1

I believe that the Escon device operated in much the same way, but from below.

In the video, that looks to be an IBM Model B typewriter--probably one of the finest of its kind and the office workhorse. I used to have the Executive proportional-spacing model of this one in my office--the copy quality was superb.

Before the Selectric came out, the Model B was used as computer console typewriter. The IBM 1620, for example used one and it always sounded like it was going to fall to pieces. I can still remember the 1620 I/O instructions for the thing--not just the SPS mnemonics (RCTY, WATY, WNTY, RATY, WNTY), but the machine code equivalents (34000000102....). Is that sick or what?

atod
December 31st, 2010, 11:50 AM
Yeah I did some reading and most of the Selectric mods either involved solenoids over the keyboard (like in video above) or some other device which was installed under the bottom access panel. The device under the bottom access panel had a number of spring loaded pins that put a set of relay contacts in
parallel with each keyboard key.

Good to know. This person has a homebrew device to interface with a modern day Brother. I think the electrical interface is simpler though:
http://numist.net/post/2010/project-typewriter.html

atod
December 31st, 2010, 11:53 AM
Also wondering. On these converted typewriters, I don't think they had holed tractor form feed. How did the paper roll stay aligned?

MikeS
December 31st, 2010, 01:11 PM
Also wondering. On these converted typewriters, I don't think they had holed tractor form feed. How did the paper roll stay aligned?You usually fed one sheet at a time by hand, although some of the commercial versions had retracting pins in the platen.

Ditto on the Executive, Chuck; had and used several myself, superb printing.

I've still got some books and articles somewhere about interfacing various Selectric versions to your home computer; I originally had a 1620 type with non-standard interface voltages and encoding that would have needed converting, but then I found a Redactron mag card word processor with a Selectric that already had a TTL-level interface and used standard type balls.

Until the market grew and inexpensive printers became available, converted typewriters were the only affordable option for many folks and there were kits for most of the electronic typewriters that were just coming on the scene then. As a matter of fact I was involved with a company that manufactured and sold interfaces for the Olivetti line of typewriters and still have a box full somewhere, but the last typewriter went to the dump a few months ago (as did the last Executive).

RickNel
December 31st, 2010, 02:04 PM
Back in 1971 I did a lot of business with a small type-setting outfit that used Selectrics linked to some kind of IBM word-processing minicomputer. We produced all the body copy for a weekly newspaper. Copy was typed up with embedded mark-up codes, similar to HTML. In print mode, that thing roared along at around 300 words per minute, but I remember that the dogs used to leave the room to escape the racket. Every time there was a change of font, the machine would stop and beep until we changed the golf-ball.

Rick

Chuck(G)
December 31st, 2010, 02:25 PM
Also wondering. On these converted typewriters, I don't think they had holed tractor form feed. How did the paper roll stay aligned?

That was one difference between the Selectric I/O and office machines. The ones destined for computer (or mag card or MT/ST) type of application like the 1052(?) on the S/360 had pin-feed or tractor-feed platens. You could also get I/O Selectrics quite a way into the 1980s. Without a controller, most used rotate-and-shift codes. I think the terminal model Selectrics ran at 134.5 baud, just a little faster than the ASR33.

tsidneyf
April 9th, 2011, 09:12 PM
IBM made a selectric Input/output writer; and it was used on their Magnetic Tape Selectric typewriter (MTST). They were hooked up to all kinds of computers in the 60's-70's. I threw a couple MTST I/O's, & computer I/O's away years ago. They were solonoid operated under the selector latches on the cycle clutch shaft. and the space bar,backspace,and carrier return cams. I doubt the selection solonoids could be duplicated using todays advanced technology. I was an IBM "technical specialist" in those days. (retired in 1988). If needed you can email me about that product. Love..."Fitz"

Forbidden64
January 9th, 2017, 09:54 PM
Hi, i just saw this thread. I have wanted to do such a mod for some time now, but don't have anything really set up to do it at the moment. There were multiple methods of doing an interface to a selectric typewriter, from replacing the keyboard with a specialized one with a board on the bottom with a full on UART and the regular mechanical select, to a solenoid solution which adapts the mechanical input in parallel wires. In the book 'TV-Typewriter Cookbook' by Don Lancaster, this method is described in detail, describing where to place the solenoids in order to do the select logic. In his setup, the Typewriter retains its daily usefulness, but also does 7 bit parallel selectric output as a printer for 'hard copy' as it was known then. He even includes the circuits for the solenoid drivers which you will need in order to power the solenoid from the actual incoming signal. His mod, however, does not provide for bidirectional I/O. Since you are intending to use it as a printer though, I don't see where that is a problem, but rather exactly what you have in mind. All you need are 10 solenoids to do the job, and some resistors and transistors etc. which are laid out in the driver circuit.

If it was 30$ back then in discrete components with solenoids, I imagine it would be even cheaper now! Wire up the driver circuits to a proto board, then get 10 solenoids and mount them in place. You could even set up something fancy like a max232 which generates the voltages for serial on board the chip and handles parallel to serial/serial to parallel I/O service for under 5$ at jameco/ebay. Just leave bit 8 open and connect the other 10 leads to their respective solenoid driver circuits. You can use pin terminals to connect the solenoids to the driver board. That way if you get them the wrong way around they are easy to readjust. Then you can do direct RS232 ouput to the printer! If you have a computer with parallel output like a commodore with adapter/ a PC, you can connect the parallel output directly and use natively.

If you want to get really really fancy, you can use a micro controller along with the max232 and make it a full on TTY automatic send recieve with all kinds of select switches with different options as you like! I do recommend if you do this, that you socket the controller and wire up extra switches in advance so you can easily add new features in the future without busting out the soldering iron and trying to remember how everything went together.

Schematics and description from page 218- from the book are linked below.

https://archive.org/stream/tvtcb_doc/tvtcb#page/n219/mode/2up

[One other thing I forgot to mention originally is that because you are only pushing the select rods, as opposed to the entire mechanism with the setup in that video, you do not need expensive high grade solenoids to do this. It is just the rods that roll into place almost like a key tumbler in a lock. Not much power required so you can use cheap solenoids.]

Forbidden64
January 9th, 2017, 11:04 PM
Still the mod looks to be expensive on looking at the price of solenoids in general...even cheap ones are around 5-7$ each. Also, another thing I overlooked is that you will have to do a conversion to selectric code...you can't just leave off a bit and they match magically. To do this, a diode matrix, or eprom will be required(the book discusses this as well). I still want to do it someday. There has to be a source of used/cheap solenoids somewhere.

DDS
January 10th, 2017, 01:16 PM
Back when I was just getting started, when Computer Sciences were still not separated out from the various Industrial Engineering and Math departments, the University of Florida student computer lab had about 30 or so I/O Selectrics. Our choices were simple, punch a deck of cards and submit as a batch job or deal with the ForTran IV interpreter through the Selectric. Those "golf balls" could raise quite a racket when a bunch of them were going at once.

snuci
January 10th, 2017, 02:33 PM
There is a book entitled, "The Selectric Interface, a Hands-On Approach" by George Young (1982). The back cover states:

"Computer printers range from small and inexpensive to costly and high quality. Selectric Interface offers another alternative -- interfacing an IBM Selectric I/O writer to a computer for printed output.

In his classroom-style approach, George Young covers different methods of interfacing. He includes information on:

6502, 8080 and Z-80 computers
Selectric models 2740, 2980 and the Dura 1041
Software needed to interface the different models
Step-by-step interfacing procedures
And more!


George Young teaches at the high school level. With his instruction and some background in hardware and interfacing, you can have a working, letter-quality printer and gain a better understanding of how it works."

I have a copy that I haven't gone through yet. Sounds like this is what is needed.

Link: https://www.thehenryford.org/collections-and-research/digital-collections/artifact/379543

Chuck(G)
January 10th, 2017, 03:43 PM
Still the mod looks to be expensive on looking at the price of solenoids in general...even cheap ones are around 5-7$ each. Also, another thing I overlooked is that you will have to do a conversion to selectric code...you can't just leave off a bit and they match magically. To do this, a diode matrix, or eprom will be required(the book discusses this as well). I still want to do it someday. There has to be a source of used/cheap solenoids somewhere.

It might be more cost-effective to find an I/O Selectric. Have you inquired on the Golf ball typewriter shop list (https://beta.groups.yahoo.com/neo/groups/golfballtypewritershop/info). There's lots of stuff there--and you may find a seller of a suitable unit.

MikeS
January 10th, 2017, 04:07 PM
There is a book entitled, "The Selectric Interface, a Hands-On Approach" by George Young (1982). The back cover states:

"Computer printers range from small and inexpensive to costly and high quality. Selectric Interface offers another alternative -- interfacing an IBM Selectric I/O writer to a computer for printed output.

In his classroom-style approach, George Young covers different methods of interfacing. He includes information on:

6502, 8080 and Z-80 computers
Selectric models 2740, 2980 and the Dura 1041
Software needed to interface the different models
Step-by-step interfacing procedures
And more!


George Young teaches at the high school level. With his instruction and some background in hardware and interfacing, you can have a working, letter-quality printer and gain a better understanding of how it works."

I have a copy that I haven't gone through yet. Sounds like this is what is needed.

Link: https://www.thehenryford.org/collections-and-research/digital-collections/artifact/379543

I've also got a copy of that book (as well as Lancaster's TVT) but it's really about the electronic aspect of interfacing & converting codes for an I/O Selectric, not much about converting a typewriter, alas. I've still got a Selectric typewriter that I vaguely dreamt about interfacing some day long ago (after having tossed out three I/O Selectrics in my even earlier foolish days...)

m

1944GPW
January 10th, 2017, 04:58 PM
I have a long-term project to get an I/O Selectric of some form going, so thanks for that info in the Lancaster book, very interesting!

Some more:
This three-part article for both I/O Selectrics and converting a regular Selectric, is very detailed
https://archive.org/details/radio_electronics_1983-12
https://archive.org/details/radio_electronics_1984-01
https://archive.org/details/radio_electronics_1984-02

Kilobaud Magazine article
https://archive.org/details/kilobaudmagazine-1978-06
https://archive.org/details/kilobaudmagazine-1978-07

Art-style project I/O selectric
https://hackaday.com/2012/06/13/turning-an-ibm-selectric-into-a-printer/

Lawrence Wilkinson's design (definately a good modern one):
https://github.com/ibm2030/IOSelectric

Another circuit:
https://www.researchgate.net/publication/226594701_A_simple_IBM_IO_Selectric_typewriter_con troller

And a very old circuit done by friends of my dad
http://www.vcfed.org/forum/entry.php?582-IBM-I-O-Selectric-terminal-interface-for-a-microcomputer-circa-1980

I have another conversion doc somewhere which I got off the web, but forgot to bookmark, but some googling ought to find this and more.

Steve.

Chuck(G)
January 10th, 2017, 05:12 PM
Well, you've got more intestinal fortitude than yours truly. Just the prospect of replacing a drive belt in a garden-variety Selectric III frightens me.

Forbidden64
January 11th, 2017, 03:34 AM
It might be more cost-effective to find an I/O Selectric. Have you inquired on the Golf ball typewriter shop list (https://beta.groups.yahoo.com/neo/groups/golfballtypewritershop/info). There's lots of stuff there--and you may find a seller of a suitable unit.

Worth a look for sure! What I really want, of course, is a teletype machine. I have a heathkit H11 and I would sure love to use it on that. Barring that though, I do already have a terminal & floppy drives, so an I/O selectric would work perfectly as a high quality printer and round out the machine nicely!

Chuck(G)
January 11th, 2017, 08:42 AM
The Greenkeys list (http://mailman.qth.net/mailman/listinfo/greenkeys) is a good place to start for TTY-related stuff.

1944GPW
January 11th, 2017, 01:40 PM
S H A D O
SUPREME HEADQUARTERS . . . . . .
ALIEN DEFENCE ORGANISATION . . .
SECRET LOCATION . . . . BENEATH FILM STUDIO

...is the first thing I would have an I/O Selectric type out :)
(From one of the coolest TV shows of my childhood, UFO)
https://www.youtube.com/watch?v=_sGZWHbyXKs

Forbidden64
January 11th, 2017, 06:32 PM
S H A D O
SUPREME HEADQUARTERS . . . . . .
ALIEN DEFENCE ORGANISATION . . .
SECRET LOCATION . . . . BENEATH FILM STUDIO

...is the first thing I would have an I/O Selectric type out :)
(From one of the coolest TV shows of my childhood, UFO)
https://www.youtube.com/watch?v=_sGZWHbyXKs

S I D
ALIEN INTRUDER DETECTOR . . .
MAINTAINING SCAN FOR UFO'S

lol that does look like a cool series! It also seems much more fun than

RAM SIZE?
WANT SIN COS?

OK

Forbidden64
January 11th, 2017, 06:56 PM
http://www.ebay.com/itm/Siemens-PT-80-teletypewriter-dot-matrix-ASR-has-tape-reader-and-punch-and-modem-/332078795601?hash=item4d51704b51:g:J9sAAOSwZQRYabg g


OH TO HAVE 250$ extra right now!!!! Look at this beauty!!! It's in my state as well...not exactly close but holy crap I would totally scoop this up if I had the chance....

cruff
January 12th, 2017, 08:06 AM
(From one of the coolest TV shows of my childhood, UFO)


That's hilarious. What was up with the purple hair on the women stationed on the moon base?

Forbidden64
January 12th, 2017, 10:56 PM
That's hilarious. What was up with the purple hair on the women stationed on the moon base?

They also have detachable sleeves and leggings! I'm watching it right now on youtube :D. I don't know why though...Moon stuff? Let's just go with moon stuff.

Forbidden64
January 13th, 2017, 01:43 PM
Back on topic though, 1944GPW, thank you so much for that list of resources... very much a definitive list of resources to get someone from selectric to I/O selectric. It seems like I/O selectrics are available off and on, but quite expensive even before you consider shipping. The best bet for finding one is probably locally/semi-locally. I see teletypes appear from time to time in craigslist. I checked out the greenkeys forums, and didn't see any buy/sell activity going on. I remember, once, I was at an E-waste facility, and I saw 2 of these being carried off to the scrap bin. They were Adler brand. I didn't know what they were at the time, and thought they were just massive typewriters. In retrospect they were probably some kind of DECwriter clone judging by their size. I would have bought them from them but I had literally no money that month extra on account of having gotten a commodore PET and a bunch of 64 peripherals. I was kicking myself because I'm sure they would have parted with them for 20$ or so.

I wish I had enough to grab that teletype though. That would be the ultimate teletype machine. Never seen one before now either.

[I just went to admire it, and not surprisingly, its already gone lol. It was a Siemens PT-80, in case the sold listing is deleted for future readers of this thread. I think I have a new dream machine to chase when things get back to normal for me.]

AndersG
January 18th, 2017, 02:59 AM
FWIW, I interfaced a Selectric to a Sinclair ZX-80 back in the days. IIRC did it have a bunch of solenoids and I controlled it through a parallell port that I built myself.

DDS
January 18th, 2017, 01:07 PM
If you had walked into a Heathkit store to purchase a brand new H-11 back in the late 70's, the hard copy device they could have sold you with the system would have been the H36 which was a rebadged Decwriter II (LA36). That machine looks a lot like a Decwriter III (LA120) which was rebadged as the Teletype TP1000 and used extensively throughout what used to be known as The Bell System. So if you're looking for a closely matching hardcopy device, the Selectric and/or Teletype 35 type machines would not be as close a match as a Decwriter II or III, rebadged or otherwise. And the TP1000 might just be easier to find. There are still gobs of them sitting around in switchrooms all over the country, some still in service as console devices for the AT&T DACSII systems. At one point we were actually using one for a door stop.

There's no telling what you might turn up if you contacted the asset recovery folks at AT&T.

Forbidden64
January 19th, 2017, 06:50 PM
If you had walked into a Heathkit store to purchase a brand new H-11 back in the late 70's, the hard copy device they could have sold you with the system would have been the H36 which was a rebadged Decwriter II (LA36). That machine looks a lot like a Decwriter III (LA120) which was rebadged as the Teletype TP1000 and used extensively throughout what used to be known as The Bell System. So if you're looking for a closely matching hardcopy device, the Selectric and/or Teletype 35 type machines would not be as close a match as a Decwriter II or III, rebadged or otherwise. And the TP1000 might just be easier to find. There are still gobs of them sitting around in switchrooms all over the country, some still in service as console devices for the AT&T DACSII systems. At one point we were actually using one for a door stop.

There's no telling what you might turn up if you contacted the asset recovery folks at AT&T.

Yes! As I have been looking for H11 stuff in another thread, I can't believe this didn't dawn on me. In fact here are some pictures from a Heathkit store in 1979 which show the demo display unit DEC LA-36 hooked up to an H11.

http://ww_heco.home.mindspring.com/omaha79.html

and of course, that would be RS232 controlled natively! One could probably use an epson LP driver and hook it up to a modern PC as well. So I think you can do a MIC drop DDS.

AdamAnt316
January 20th, 2017, 07:08 AM
I recently picked up a blue Correcting Selectric II (http://coolstuff4819.blogspot.com/2016/07/1973-ibm-correcting-selectric-ii.html) at a Goodwill store for $4. The mechanism occasionally gets hung up, but it works pretty well overall. Not capable of being hooked to a computer without one of those solenoid contraptions, but it works quite nicely as a regular typewriter. Rather crazy to think about the 'whiffletree' mechanism (https://en.wikipedia.org/wiki/IBM_Selectric_typewriter#Selectric_mechanism) it uses to turn keypresses into typeball movement at a (relatively) rapid pace! Sort of a mechanical digital computer in it's own right... ;-)
-Adam

roberttx
January 20th, 2017, 02:49 PM
A little OT (but the thread has drifted, so I don't think it's too OT) but a thrift store near me has an IBM Wheelwriter III. I didn't see the price, but knowing them it will be $30 or so.

ISTR that they could be used as a printer. Is that right and, if so, do I want it?

vwestlife
January 20th, 2017, 04:01 PM
A little OT (but the thread has drifted, so I don't think it's too OT) but a thrift store near me has an IBM Wheelwriter III. I didn't see the price, but knowing them it will be $30 or so.

ISTR that they could be used as a printer. Is that right and, if so, do I want it?

An IBM Wheelwriter is a daisywheel printer with a keyboard attached to it (a very nice buckling-spring mechanical keyboard!). A printer interface was an optional extra. Not all have it, but if this one does, you'll see a box attached to the back with a Centronics parallel port on it (I suppose a serial port version was also available).

roberttx
January 21st, 2017, 05:38 AM
An IBM Wheelwriter is a daisywheel printer with a keyboard attached to it (a very nice buckling-spring mechanical keyboard!). A printer interface was an optional extra. Not all have it, but if this one does, you'll see a box attached to the back with a Centronics parallel port on it (I suppose a serial port version was also available).

Thanks. So, I guess I want it. The store is in a nearby city, about 50 miles away, but I'll be there Monday so I'll stop by and see if they still have it.

1944GPW
January 21st, 2017, 01:26 PM
An IBM Wheelwriter is a daisywheel printer with a keyboard attached to it (a very nice buckling-spring mechanical keyboard!). A printer interface was an optional extra. Not all have it, but if this one does, you'll see a box attached to the back with a Centronics parallel port on it (I suppose a serial port version was also available).

There was an article on Hackaday just last week about tapping in to the logic of a regular Wheelwriter and using it as a printer: http://hackaday.com/2017/01/14/vintage-ibm-daisywheel-prints-again-after-reverse-engineering/
Also, I seem to recall one of the VCF members here - perhaps it was Mattis, or Pontus? - had written about doing a similar Wheelwriter adaptation some months ago, but am not sure about the details.

roberttx
January 21st, 2017, 02:35 PM
There was an article on Hackaday just last week about tapping in to the logic of a regular Wheelwriter and using it as a printer: http://hackaday.com/2017/01/14/vintage-ibm-daisywheel-prints-again-after-reverse-engineering/
Also, I seem to recall one of the VCF members here - perhaps it was Mattis, or Pontus? - had written about doing a similar Wheelwriter adaptation some months ago, but am not sure about the details.

That's excellent, thanks! Let's hope it's still there when I go back on Monday.

AdamAnt316
January 21st, 2017, 02:48 PM
That's excellent, thanks! Let's hope it's still there when I go back on Monday.

If it somehow isn't still there, it shouldn't be hard to find another one. Wheelwriters are still being made by Lexmark, AFAIK, and I see them all the time at banks and other businesses. I found mine (a Wheelwriter 2000) at a surplus electronics store for $10, and I've seen Wheelwriters for sale in thrift stores and other such places as well.
-Adam

1944GPW
January 21st, 2017, 05:17 PM
If you had walked into a Heathkit store to purchase a brand new H-11 back in the late 70's, the hard copy device they could have sold you with the system would have been the H36 which was a rebadged Decwriter II (LA36).

I have a Fall 1978 DEC Sales Catalog and the list price of a bare-bones LA36 DECwriter II back then was from $1595 upwards. With optional extras of a 14-key keypad, 20mA current loop interface, paper-out sensor, extra ribbon and 90-day on-site warranty it was $1825. The faster LA120 DECwriter III was even more expensive starting at $3072.
I have no idea what was Heathkit's price for the rebadged unit, but according to the inflation calculator $1595 is over $5800 in today's dollars so it's no wonder people were looking for all sorts of cheaper printing alternatives.

Forbidden64
January 23rd, 2017, 01:56 AM
I have a Fall 1978 DEC Sales Catalog and the list price of a bare-bones LA36 DECwriter II back then was from $1595 upwards. With optional extras of a 14-key keypad, 20mA current loop interface, paper-out sensor, extra ribbon and 90-day on-site warranty it was $1825. The faster LA120 DECwriter III was even more expensive starting at $3072.
I have no idea what was Heathkit's price for the rebadged unit, but according to the inflation calculator $1595 is over $5800 in today's dollars so it's no wonder people were looking for all sorts of cheaper printing alternatives.

Ya no kidding! It must also be the reason why the Heath 11, and it's companion peripherals are so rare in general. The floppy was $2595 assembled back then. The computer was $1295 in kit form...then hardcopy for another $1600 and terminal for $800. All together you could put a down a sizable down payment on a house, or get a fully loaded H-11. That's not even including memory expansions, and extra cards you would want/need, and the operating system! Thankfully, at least the operating system came with some decent languages, like a very capable BASIC.

I suppose technically you could get away with buying the base unit, using HASSL (ironically named) assembler, and a kit paper tape machine with an homebrew I/O selectric. You then would need one parallel card, one serial card and a printer terminal. That would still be expensive, but you would have some crazy computing power in comparison to most individual people back then, but most didn't do that. Point being, if you got one of these...price was clearly no object, and it shows in the examples of the machine which remain. Almost all of them I have seen are nearly fully populated bus systems, fully expanded memory, with terminals, disk drives, paper tape, and a slew of other goodies. Probably because they were going to buy a DEC and got wind they could get one for thousands less from Heath, so they went nuts and bought all the extras.

krebizfan
January 23rd, 2017, 07:17 AM
I knew of a few H-11's sold in northern New Jersey before 1980 and all used third party printers. The fully loaded complete H-11 was a good value at the time, not that much more than a S-100 system with dual 8" floppy drives.

Forbidden64
January 24th, 2017, 03:35 AM
I knew of a few H-11's sold in northern New Jersey before 1980 and all used third party printers. The fully loaded complete H-11 was a good value at the time, not that much more than a S-100 system with dual 8" floppy drives.

I guess when you put it that way, ya. Did most people finance these computers? I saw a few companies were doing that in magazines. 78$/month for 12 months or whatever.

Jim27
January 29th, 2017, 05:40 AM
Around 1979 I purchased a worn out IO Selectric used, I think, by the airlines to print tickets. It had solenoids under the keyboard to trip the "interposers" (think that is the term for the cross rods under the keyboard). The tilt and rotate actuation did not match a standard desktop selectric so standard type balls were not compatible. I rearranged the parts under the keys that had the interposer/tilt-rotate coding (mechanical tangs) so that it was standard. Built a driver board to interface the 48V solenoids. Then wrote a CPM program to convert from ascii to tilt-rotate codes. It worked. Might have the code around somewhere but it was pretty simple - just keep track of the shift state and then a lookup table. I think I made it part of the bios (on a BBII) but don't remember all the details. But the unit was very worn and never worked well. I tossed it out in a move many years ago but still have the allen type wrenches (bristol?) and the wheel for manually turning over the selectric mechanism. No longer any use to me so should look at selling them. Was quite an interesting project.

Forbidden64
January 29th, 2017, 02:43 PM
Sounds like it! A computer pioneer project if I ever heard one!

durgadas311
March 7th, 2017, 08:59 AM
Wang Laboratories used their own patented modification to IBM selectrics for printers on their programmable calculators and other computers. You might be able to find those around, I have seen them occasionally. They should not be too difficult to interface to a parallel port. Most allow keyboard to be used (offline), some even as a complete terminal (full I/O). They were called "Output Writers" or "I/O Writers" in Wang documentation.

durgadas311
March 8th, 2017, 06:04 AM
I probably over-simplified the use of a Wang OutputWriter. The parallel port interface would be relatively simple, but the software is not so much. The device uses a 6-bit "rotate-tilt" code (not ASCII) plus the computer needs to manage SHIFT state and, of course, delays for mechanical operations (as I recall, the one handshake signal does not cover the time it takes to perform the mechanicals). I worked out most of that for the Wang simulations I did (no mechanical delays required), but it would still be "interesting" code to write for CP/M. "Fun", or not, depending on your point of view.

g4ugm
March 9th, 2017, 01:30 AM
I probably over-simplified the use of a Wang OutputWriter. The parallel port interface would be relatively simple, but the software is not so much. The device uses a 6-bit "rotate-tilt" code (not ASCII) plus the computer needs to manage SHIFT state and, of course, delays for mechanical operations (as I recall, the one handshake signal does not cover the time it takes to perform the mechanicals). I worked out most of that for the Wang simulations I did (no mechanical delays required), but it would still be "interesting" code to write for CP/M. "Fun", or not, depending on your point of view.

Many of the designs I have seen use an EPROM to convert from ASCII to tile/rotate code. There are 4 rows of 22 characters on an 88 character ball, so that's 2 bits for the tilt and 5 bits for the rotate. The spare bit can be used to trigger the other functions....

Klyball
March 11th, 2019, 07:47 AM
I was reading this thread and looking at the links and thought it would be cool to have a golf ball typewriter for a terminal running focal on the ohio scientific 560z. After doing a pile of research I decided the easiest way would be to use a ibm electronic 50-85 series typewriter. They are a hybrid that squeezes in between the completely mechanical selectric and wheelwriter. After searching ,a local fellow answered a add i had , he had a electronic 50 he wanted to give away. When I picked it it up he also had a selectric ii from 1974 so I grabbed that too. After going on some typewriter groups I soon discovered that those 50-85 series are very unreliable .hard to fix and parts are unobtainium. But to my surprise that selectric ii had a computer interface already attached to it.
It is made up of 14 solenoids and 17 switches that control all the mechanicals. These typewriter are a mechanical nightmare, and super complicated arrangement of clutches ,gears and pulleys. It so happen we have a guy around here who still repairs these things, so I took it to him to get it working. He said it not worth fixing your better off buying a refurbished machine.well I decided I'm gonna fix it and I did, after hours of reading ,hours of videos ,hours of cleaning and de greasing, some new parts its almost as good as new. Next step was to figure out how to interface to the computer, there is a control board on the unit for solenoids and switches. I designed up a circuit to connect to the computer and wrote some firmware. I am just waiting for the cable and I'm ready to test.
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durgadas311
March 11th, 2019, 12:59 PM
Well done! That's no small feat!

Any idea if the computer interface was standard equipment, or from some third-party? any info on what the pin-out, and protocol, is?