Anyone using an ASR-33 teletype with a Telebyte 65A converter? - CP/M

This is a discussion on Anyone using an ASR-33 teletype with a Telebyte 65A converter? - CP/M ; ArarghMail810NOSPAM@NOT.AT.Arargh.com wrote: > CBFalconer wrote: > .... snip ... > >> My major memory is that they had to be turned off, otherwise the >> engaging clutches would seize up within a year. Our applications >> needed them running, so ...

+ Reply to Thread
Page 2 of 3 FirstFirst 1 2 3 LastLast
Results 21 to 40 of 45

Thread: Anyone using an ASR-33 teletype with a Telebyte 65A converter?

  1. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?

    ArarghMail810NOSPAM@NOT.AT.Arargh.com wrote:
    > CBFalconer wrote:
    >

    .... snip ...
    >
    >> My major memory is that they had to be turned off, otherwise the
    >> engaging clutches would seize up within a year. Our applications
    >> needed them running, so they could receive medical messages.

    >
    > I am pretty sure that TTYs required routine preventive maintenance.
    > I once knew a firm that did just that.
    >
    >> We were saved when Epsom printers appeared, i.e. the MX80.

    >
    > When those kinds of printers started appearing, the owner of that
    > same firm did some tests. He would connect the printer to a
    > character generater, give it all the paper it wanted, and wait
    > until it died. The only printer that he gave up on waiting to die
    > was an OkiData ML82. I bought one of them in about 1976. Still
    > have it. Still works as of the last time I used it some 5 or 10
    > years ago. I would probably have trouble finding ribbons for it
    > now - Okidata ribbons, that is.


    Well, when we found the Epsons there was no OkiData. Besides
    holding up the Epsons cost about $500 in place of $1000, with a
    RS232 interface. The users would never change the ribbons, so
    reading required some care later, and my technicians could do their
    magic. Besides which they were 3 times faster, 10 times more
    quiet, and much smaller.

    --
    [mail]: Chuck F (cbfalconer at maineline dot net)
    [page]:
    Try the download section.

  2. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?

    > On my system, I added a toggle switch on the back panel that switches
    > between 9600 baud 8N1 and 110 baud 7E2. I set it to 110 when I want to use
    > the TTY (and then feed the RS-232 to a Telebyte 20ma converter), and 9600
    > for CRT.


    Are you sure your serial board is only for one port?
    8250 UART chips wouldn't be the right vintage would they?
    I know it might sound like a really dumb question...
    I got what the theory was with parity bits, but
    in practice, there wasn't any provision for a
    bad byte to be sent over again was there?

    (I looked)
    http://en.wikipedia.org/wiki/Parity_bit

    20ma was all about long lines, pointless when
    using the TTY next to an Altair right?

    Wasn't parity also similarly pointless on short lines?

    When entering a source text tape with parity,
    if there is so much as one bad parity, what
    would tell you that and what exactly would
    you do about it?

    How exactly were binary tapes used to enter
    the machine code with a 7E2 scheme?

    Doesn't it HAVE TO be 8,N,2 to do binary tapes?

    TTY33's can be configured for 8N2 can't they?

    > I guess I'm spoiled; I
    > like to do my development work on the PC using cross assemblers/compilers
    > and then zap the finished product over to the Altair.


    Wouldn't the B model with MITS FLOPPY DISK DRIVES
    be less like cheating?
    That's what I got spoiled with back then.

    > >> I have the TTY (an ASR-33 with tape reader/punch) connected to a vintage
    > >> Altair 8800 running MITS 4K Basic. I wanted a "snapshot" of a particular
    > >> time in history


    > >> for this machine.

    -----------------------

    Oh rats! I was going to suggest you get
    a batch mode DRUM printer to actually work right.
    Bap Bap Bap Bap Bap! ....

    Right era, but not "for this machine"...

    > Nothing like the flicker of LEDs, the smell of hot oil, and earplugs.


    LOL!

    > For those unfamiliar with working on those old beasts - it's more like
    > working on your car than a computer... there's belts, camshafts, oil,
    > relays, a distributor, a motor... and not a chip in sight. Although there a
    > a few power transistors in mine.


    Even an OPERATOR can't overlook all of that!

  3. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?

    Greegor wrote:
    (snip)

    > 20ma was all about long lines, pointless when
    > using the TTY next to an Altair right?


    I thought it was directly to the solenoid which then
    drives whatever mechanical linkage decodes the ASCII.
    (The height and rotation of the print drum.)

    The UART is mechanical.

    -- glen


  4. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?

    On Thu, 30 Oct 2008 21:22:45 -0500, CBFalconer
    wrote:

    >ArarghMail810NOSPAM@NOT.AT.Arargh.com wrote:
    >> CBFalconer wrote:


    >> When those kinds of printers started appearing, the owner of that
    >> same firm did some tests. He would connect the printer to a
    >> character generater, give it all the paper it wanted, and wait
    >> until it died. The only printer that he gave up on waiting to die
    >> was an OkiData ML82. I bought one of them in about 1976. Still
    >> have it. Still works as of the last time I used it some 5 or 10
    >> years ago. I would probably have trouble finding ribbons for it
    >> now - Okidata ribbons, that is.

    >
    >Well, when we found the Epsons there was no OkiData. Besides
    >holding up the Epsons cost about $500 in place of $1000, with a
    >RS232 interface. The users would never change the ribbons, so
    >reading required some care later, and my technicians could do their
    >magic. Besides which they were 3 times faster, 10 times more
    >quiet, and much smaller.

    I presume you are comparing against TTYs. :-)

    I have no idea just when the smaller printers started to appear. The
    only date I am reasonably sure of is that Hazeltine 2000 terminals
    were available by at least 1972, which is when I started seeing ads
    for them. :-)
    --
    ArarghMail810 at [drop the 'http://www.' from ->] http://www.arargh.com
    BCET Basic Compiler Page: http://www.arargh.com/basic/index.html

    To reply by email, remove the extra stuff from the reply address.

  5. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?


    "Greegor" wrote in message
    news:3382cf5c-025e-4981-a9af-8980a4c73686@i24g2000prf.googlegroups.com...
    >> On my system, I added a toggle switch on the back panel that switches
    >> between 9600 baud 8N1 and 110 baud 7E2. I set it to 110 when I want to
    >> use
    >> the TTY (and then feed the RS-232 to a Telebyte 20ma converter), and 9600
    >> for CRT.

    >
    > Are you sure your serial board is only for one port?
    > 8250 UART chips wouldn't be the right vintage would they?
    > I know it might sound like a really dumb question...
    > I got what the theory was with parity bits, but
    > in practice, there wasn't any provision for a
    > bad byte to be sent over again was there?
    >



    I have an SIO-A in my 8800. The 2-SIO had two ports, but mine has only one,
    hence the toggle switch.

    Parity is not a foolproof way to stop errors. You have to wait until the
    Xmodem protocol becomes popular a few years later. But then, at a whopping
    110 baud, you need some serious noise to make a dent in your data.


    > (I looked)
    > http://en.wikipedia.org/wiki/Parity_bit
    >
    > 20ma was all about long lines, pointless when
    > using the TTY next to an Altair right?
    >


    Hey, I didn't design the ASR-33. It comes with 20ma current loop from the
    factory, and all my machines use RS-232. I didn't try to analyze the
    Teletype design, I just got a converter so everything could talk together.

    > Wasn't parity also similarly pointless on short lines?
    >
    > When entering a source text tape with parity,
    > if there is so much as one bad parity, what
    > would tell you that and what exactly would
    > you do about it?
    >
    > How exactly were binary tapes used to enter
    > the machine code with a 7E2 scheme?
    >
    > Doesn't it HAVE TO be 8,N,2 to do binary tapes?
    >
    > TTY33's can be configured for 8N2 can't they?
    >


    I'm pretty sure TTY machines can be reconfigured to some extent, but the
    exact details on how to do this are probably better asked from someone like
    Wayne, since he's the expert on TTY machines. One thing I know for sure is
    that if you look at an ASR-33 paper tape, you see 8 holes across it. I also
    know that Gates/Allen didn't use a simple binary file for Basic. It was a 2
    stage loader. The first was toggled into the front panel by the user, the
    second was loaded from the tape and took over the loading job while the tape
    was reading.


    >> I guess I'm spoiled; I
    >> like to do my development work on the PC using cross assemblers/compilers
    >> and then zap the finished product over to the Altair.

    >
    > Wouldn't the B model with MITS FLOPPY DISK DRIVES
    > be less like cheating?
    > That's what I got spoiled with back then.
    >


    Yep, that would be a good plan. I have an 8800B too and a single MITS disk
    drive for it. If only I could get it working, I'd be a happy camper! But
    alas, my soft human brain can only process one project at a time Right
    now, I have the B running with a MITS ROM Basic card so it boots straight to
    extended Basic.


    >> >> I have the TTY (an ASR-33 with tape reader/punch) connected to a
    >> >> vintage
    >> >> Altair 8800 running MITS 4K Basic. I wanted a "snapshot" of a
    >> >> particular
    >> >> time in history

    >
    >> >> for this machine.

    > -----------------------
    >
    > Oh rats! I was going to suggest you get
    > a batch mode DRUM printer to actually work right.
    > Bap Bap Bap Bap Bap! ....
    >
    > Right era, but not "for this machine"...
    >
    >> Nothing like the flicker of LEDs, the smell of hot oil, and earplugs.

    >
    > LOL!
    >
    >> For those unfamiliar with working on those old beasts - it's more like
    >> working on your car than a computer... there's belts, camshafts, oil,
    >> relays, a distributor, a motor... and not a chip in sight. Although
    >> there a
    >> a few power transistors in mine.

    >
    > Even an OPERATOR can't overlook all of that!


    You know, for a while I ran the TTY sans stand on a table next to the
    Altair. I found my software kept locking up the Altair and I couldn't find
    the bug in the software. Well.... it turned out that the TTY was shaking
    the table so much I was getting intermittent contact on some of my S-100
    cards! I bolted the TTY back on it's stand and it was smooth sailing from
    then on.

    -J



  6. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?


    "Tom Lake" wrote in message
    news:gee81g$8ci$1@news.albasani.net...
    >>> Is there any chance I could get a paper tape copy of 4K BASIC from you?
    >>> I'd
    >>> send you an entire roll of paper tape as payment and you could send
    >>> back the copy. Do you have 8K or 12K Extended BASIC on paper tape or
    >>> cassette?
    >>> I'm looking for those, too.
    >>>
    >>> Tom Lake

    >>
    >> Hey Tom,
    >>
    >> Sounds like we're working on similar systems! Good luck on that Stockley
    >> kit. I've got one of his 680's, and I'm very impressed with his
    >> attention to detail. A good engineer and a real go-getter. Picking up
    >> the pieces after 35+ years is no small feat.
    >>
    >> I'll email you the MITS BASIC files. You can send these out to your TTY
    >> and punch the tapes yourself. Use a non-protocol binary transfer.
    >> Hyperterm doesn't do it, but try Tera Term Pro.

    >
    > Thanks! I do have one question, though:
    > The Teletype only works at 7 bits, Even parity. How would a binary
    > file transmit properly?
    >
    > Tom Lake


    Tom,

    By "binary" I meant the original MITS paper tape files. These are not
    straight binary images of Basic as it lays in memory, but contain a built in
    2nd stage loader program (courtesy of Gates/Allen). You need to use the
    appropriate 1st stage loader toggled into the front panel. If you have the
    Altair Basic doc set, the loaders should be in there. They are
    intentionally rather short. Note that each Basic has it's own loader.

    To make a tape copy just connect your terminal emulator to your TTY and send
    it over with the punch turned on. No need to even fire up the Altair.


    -John




  7. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?


    "Tom Lake" wrote in message
    news:gee81g$8ci$1@news.albasani.net...
    >>> Is there any chance I could get a paper tape copy of 4K BASIC from you?
    >>> I'd
    >>> send you an entire roll of paper tape as payment and you could send
    >>> back the copy. Do you have 8K or 12K Extended BASIC on paper tape or
    >>> cassette?
    >>> I'm looking for those, too.
    >>>
    >>> Tom Lake

    >>
    >> Hey Tom,
    >>
    >> Sounds like we're working on similar systems! Good luck on that Stockley
    >> kit. I've got one of his 680's, and I'm very impressed with his
    >> attention to detail. A good engineer and a real go-getter. Picking up
    >> the pieces after 35+ years is no small feat.
    >>
    >> I'll email you the MITS BASIC files. You can send these out to your TTY
    >> and punch the tapes yourself. Use a non-protocol binary transfer.
    >> Hyperterm doesn't do it, but try Tera Term Pro.

    >
    > Thanks! I do have one question, though:
    > The Teletype only works at 7 bits, Even parity. How would a binary
    > file transmit properly?
    >
    > Tom Lake


    Come to think of it, I'm not sure of the exact format MITS used for encoding
    the programs on tape. It would be interesting research, I'm sure. I do
    know SWTPC 6800/Motorola/Mikbug just used ASCII Hexadecimal chars in the "S"
    files.

    -J



  8. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?



    "John Crane" wrote in message
    newsrWdnet9rrrI9ZbUnZ2dnUVZ_hadnZ2d@pghconnect.com...
    >
    > "Tom Lake" wrote in message
    > news:gee81g$8ci$1@news.albasani.net...
    >>>> Is there any chance I could get a paper tape copy of 4K BASIC from you?
    >>>> I'd
    >>>> send you an entire roll of paper tape as payment and you could send
    >>>> back the copy. Do you have 8K or 12K Extended BASIC on paper tape or
    >>>> cassette?
    >>>> I'm looking for those, too.
    >>>>
    >>>> Tom Lake
    >>>
    >>> Hey Tom,
    >>>
    >>> Sounds like we're working on similar systems! Good luck on that
    >>> Stockley kit. I've got one of his 680's, and I'm very impressed with
    >>> his attention to detail. A good engineer and a real go-getter. Picking
    >>> up the pieces after 35+ years is no small feat.
    >>>
    >>> I'll email you the MITS BASIC files. You can send these out to your
    >>> TTY and punch the tapes yourself. Use a non-protocol binary transfer.
    >>> Hyperterm doesn't do it, but try Tera Term Pro.

    >>
    >> Thanks! I do have one question, though:
    >> The Teletype only works at 7 bits, Even parity. How would a binary
    >> file transmit properly?
    >>
    >> Tom Lake

    >
    > Tom,
    >
    > By "binary" I meant the original MITS paper tape files. These are not
    > straight binary images of Basic as it lays in memory, but contain a built
    > in 2nd stage loader program (courtesy of Gates/Allen). You need to use
    > the appropriate 1st stage loader toggled into the front panel. If you
    > have the Altair Basic doc set, the loaders should be in there. They are
    > intentionally rather short. Note that each Basic has it's own loader.
    >
    > To make a tape copy just connect your terminal emulator to your TTY and
    > send it over with the punch turned on. No need to even fire up the
    > Altair.


    OK, I can punch the tape but how can I keep the characters from printing
    as I'm sending the data. I know the control characters to turn the tape
    reader/punch on and off but I was sure there was a way to be able to
    punch or read a tape without the printer actually typing. I punched the 4K
    tape and wasted quite a bit of ribbon and paper. I will hold off on the 8K
    and Extended tapes until I can find out how to keep from printing what
    I'm loading from paper tape.

    Tom Lake


  9. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?


    "Tom Lake" wrote in message
    news:gego2t$alm$1@news.albasani.net...
    >
    >
    > "John Crane" wrote in message
    > newsrWdnet9rrrI9ZbUnZ2dnUVZ_hadnZ2d@pghconnect.com...
    >>
    >> "Tom Lake" wrote in message
    >> news:gee81g$8ci$1@news.albasani.net...
    >>>>> Is there any chance I could get a paper tape copy of 4K BASIC from
    >>>>> you? I'd
    >>>>> send you an entire roll of paper tape as payment and you could send
    >>>>> back the copy. Do you have 8K or 12K Extended BASIC on paper tape or
    >>>>> cassette?
    >>>>> I'm looking for those, too.
    >>>>>
    >>>>> Tom Lake
    >>>>
    >>>> Hey Tom,
    >>>>
    >>>> Sounds like we're working on similar systems! Good luck on that
    >>>> Stockley kit. I've got one of his 680's, and I'm very impressed with
    >>>> his attention to detail. A good engineer and a real go-getter.
    >>>> Picking up the pieces after 35+ years is no small feat.
    >>>>
    >>>> I'll email you the MITS BASIC files. You can send these out to your
    >>>> TTY and punch the tapes yourself. Use a non-protocol binary transfer.
    >>>> Hyperterm doesn't do it, but try Tera Term Pro.
    >>>
    >>> Thanks! I do have one question, though:
    >>> The Teletype only works at 7 bits, Even parity. How would a binary
    >>> file transmit properly?
    >>>
    >>> Tom Lake

    >>
    >> Tom,
    >>
    >> By "binary" I meant the original MITS paper tape files. These are not
    >> straight binary images of Basic as it lays in memory, but contain a built
    >> in 2nd stage loader program (courtesy of Gates/Allen). You need to use
    >> the appropriate 1st stage loader toggled into the front panel. If you
    >> have the Altair Basic doc set, the loaders should be in there. They are
    >> intentionally rather short. Note that each Basic has it's own loader.
    >>
    >> To make a tape copy just connect your terminal emulator to your TTY and
    >> send it over with the punch turned on. No need to even fire up the
    >> Altair.

    >
    > OK, I can punch the tape but how can I keep the characters from printing
    > as I'm sending the data. I know the control characters to turn the tape
    > reader/punch on and off but I was sure there was a way to be able to
    > punch or read a tape without the printer actually typing. I punched the
    > 4K
    > tape and wasted quite a bit of ribbon and paper. I will hold off on the
    > 8K
    > and Extended tapes until I can find out how to keep from printing what
    > I'm loading from paper tape.
    >
    > Tom Lake



    Heck, I just take the paper & ribbon out. I haven't found an "elegant" way
    to do it. A copy of BASIC on tape is nice to have, but I only did it once.
    When I got mine loaded, I zapped it to ROM. I modified my Monitor chip to
    have a routine to copy the last 4K of memory (the ROMS) into the 1st 4K of
    memory and voila! I can load BASIC in about 1 second (silently, too).

    I can see the historical value of loading from an actual paper tape, though.
    That's why I still have that option. But I tend to keep those loads
    restricted to demonstrations. I wouldn't want to run the tape reader/punch
    all the time, or even the TTY printer for that matter for fear of wear &
    tear, not to mention the time/noise. Anything with moving parts will
    eventually wear out. That's why I mostly use the ROM and 9600 RS-232 for
    general tinkering when I'm not showing the newbies the joys of old geezer
    computing.

    Microsoft made it a little easier in the 8K and Extended Basics. When you
    READ a tape (a Basic program) into the machine, you can avoid printing the
    Basic source by typing a Control-O.

    -J



  10. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?

    John Crane wrote:
    (snip)

    > I can see the historical value of loading from an actual paper tape, though.
    > That's why I still have that option. But I tend to keep those loads
    > restricted to demonstrations. I wouldn't want to run the tape reader/punch
    > all the time, or even the TTY printer for that matter for fear of wear &
    > tear, not to mention the time/noise.


    From the Altair days I remember optical paper tape readers with
    phototransistors for the eight data columns and the index position
    that would read as fast as you could pull the tape through, no
    mechanical parts to wear out.

    -- glen


  11. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?

    >> OK, I can punch the tape but how can I keep the characters from printing
    >> as I'm sending the data. I know the control characters to turn the tape
    >> reader/punch on and off but I was sure there was a way to be able to
    >> punch or read a tape without the printer actually typing. I punched the
    >> 4K
    >> tape and wasted quite a bit of ribbon and paper. I will hold off on the
    >> 8K
    >> and Extended tapes until I can find out how to keep from printing what
    >> I'm loading from paper tape.


    >
    > Heck, I just take the paper & ribbon out. I haven't found an "elegant"
    > way to do it. A copy of BASIC on tape is nice to have, but I only did it
    > once. When I got mine loaded, I zapped it to ROM. I modified my Monitor
    > chip to have a routine to copy the last 4K of memory (the ROMS) into the
    > 1st 4K of memory and voila! I can load BASIC in about 1 second (silently,
    > too).


    OK, I got an answer from Wayne Durkee. My memory is faulty. I was sure
    there
    was a key combination to do it but there's not. He did say this, though:

    "There are no keys to hit, but if you open the lid w/window, and look at the
    code bars running left and right under the carriage (there are about 8 or 9
    of them), look at the right side and locate the PS (print suppress) codebar,
    I think its the rearmost one. It is labeled P over S on the spring holder
    bar.
    If you hold that bar from coming up with a dowel cut to size or some other
    ingenious method, it will stop printing while punching. Try it with a long
    dowel or tool to see if it works first. You can use the protrusion on the
    right
    side of the bar, I believe. "

    Tom Lake




  12. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?

    "Glen Herrmannsfeldt" wrote in message
    news:geis9v$22f$1@aioe.org...
    > John Crane wrote:
    > (snip)


    > From the Altair days I remember optical paper tape readers with
    > phototransistors for the eight data columns and the index position
    > that would read as fast as you could pull the tape through, no
    > mechanical parts to wear out.


    There's a guy who still sells those on eBay. They're BIN @ $175.00
    but I need a punch as well and I only have serial ports and his unit
    uses a parallel port.

    Tom Lake


  13. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?


    "Tom Lake" wrote in message
    news:geitdm$d4e$1@news.albasani.net...
    > "Glen Herrmannsfeldt" wrote in message
    > news:geis9v$22f$1@aioe.org...
    >> John Crane wrote:
    >> (snip)

    >
    >> From the Altair days I remember optical paper tape readers with
    >> phototransistors for the eight data columns and the index position
    >> that would read as fast as you could pull the tape through, no
    >> mechanical parts to wear out.

    >
    > There's a guy who still sells those on eBay. They're BIN @ $175.00
    > but I need a punch as well and I only have serial ports and his unit
    > uses a parallel port.
    >
    > Tom Lake


    Those early ones were ususally made by Oliver Audio Engineering. Very nice
    design.

    -J



  14. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?


    "Tom Lake" wrote in message
    news:geisk7$cao$1@news.albasani.net...
    >>> OK, I can punch the tape but how can I keep the characters from printing
    >>> as I'm sending the data. I know the control characters to turn the tape
    >>> reader/punch on and off but I was sure there was a way to be able to
    >>> punch or read a tape without the printer actually typing. I punched the
    >>> 4K
    >>> tape and wasted quite a bit of ribbon and paper. I will hold off on the
    >>> 8K
    >>> and Extended tapes until I can find out how to keep from printing what
    >>> I'm loading from paper tape.

    >
    >>
    >> Heck, I just take the paper & ribbon out. I haven't found an "elegant"
    >> way to do it. A copy of BASIC on tape is nice to have, but I only did it
    >> once. When I got mine loaded, I zapped it to ROM. I modified my Monitor
    >> chip to have a routine to copy the last 4K of memory (the ROMS) into the
    >> 1st 4K of memory and voila! I can load BASIC in about 1 second
    >> (silently, too).

    >
    > OK, I got an answer from Wayne Durkee. My memory is faulty. I was sure
    > there
    > was a key combination to do it but there's not. He did say this, though:
    >
    > "There are no keys to hit, but if you open the lid w/window, and look at
    > the
    > code bars running left and right under the carriage (there are about 8 or
    > 9
    > of them), look at the right side and locate the PS (print suppress)
    > codebar,
    > I think its the rearmost one. It is labeled P over S on the spring holder
    > bar.
    > If you hold that bar from coming up with a dowel cut to size or some other
    > ingenious method, it will stop printing while punching. Try it with a
    > long
    > dowel or tool to see if it works first. You can use the protrusion on the
    > right
    > side of the bar, I believe. "
    >
    > Tom Lake
    >
    >
    >


    Do you have to do this while the thing is running?

    I get this nasty vision of why they tell you to never wear neckties when you
    work on your car with the engine running...

    -J



  15. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?

    >> "There are no keys to hit, but if you open the lid w/window, and look at the
    >> code bars running left and right under the carriage (there are about 8 or 9
    >> of them), look at the right side and locate the PS (print suppress) codebar,
    >> I think its the rearmost one. It is labeled P over S on the spring holder
    >> bar.
    >> If you hold that bar from coming up with a dowel cut to size or some other
    >> ingenious method, it will stop printing while punching. Try it with a long
    >> dowel or tool to see if it works first. You can use the protrusion on the
    >> right
    >> side of the bar, I believe. "



    > Do you have to do this while the thing is running?
    >
    > I get this nasty vision of why they tell you to never wear neckties when you
    > work on your car with the engine running...


    Ow! 8^) Anything that can keep the bar down will work. You can set it up
    with the 33 off then turn it on. With the way you do it, doesn't the striker
    still hit the type cylinder? That would wear it out just as if you were
    printing.

    Tom Lake


  16. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?

    John Crane wrote:

    > I get this nasty vision of why they tell you to never wear neckties when you
    > work on your car with the engine running...


    I don't remember it with the ASR33, but the IBM 2741 terminal has
    a rod the whole length (the carriage rides on this rod) that rotates
    once per character. There have been stories of ties caught in those.
    Ones I used to know had a plastic sheet over the top to help
    prevent that. (Added later, not an IBM product.)

    -- glen


  17. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?

    Glen Herrmannsfeldt wrote:
    > John Crane wrote:
    >
    >> I get this nasty vision of why they tell you to never wear
    >> neckties when you work on your car with the engine running...

    >
    > I don't remember it with the ASR33, but the IBM 2741 terminal has
    > a rod the whole length (the carriage rides on this rod) that
    > rotates once per character. There have been stories of ties
    > caught in those. Ones I used to know had a plastic sheet over the
    > top to help prevent that. (Added later, not an IBM product.)


    I never realized that IBM was in the tie manufacturing business.
    :-)

    --
    [mail]: Chuck F (cbfalconer at maineline dot net)
    [page]:
    Try the download section.

  18. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?

    Tom Lake wrote:
    (snip, I wrote)

    >> From the Altair days I remember optical paper tape readers with
    >> phototransistors for the eight data columns and the index position
    >> that would read as fast as you could pull the tape through, no
    >> mechanical parts to wear out.


    > There's a guy who still sells those on eBay. They're BIN @ $175.00
    > but I need a punch as well and I only have serial ports and his unit
    > uses a parallel port.


    That seems pretty expensive to me. The one I remember was mostly
    just the phototransistors and buffers, and latches the data on
    the index hole.

    -- glen


  19. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?

    CBFalconer wrote:
    (snip)

    > I never realized that IBM was in the tie manufacturing business.


    Stories I used to hear were that all IBM employees except
    physicists were required to wear ties to work. That would
    include many engineers working on things with moving parts.

    -- glen


  20. Re: Anyone using an ASR-33 teletype with a Telebyte 65A converter?

    >> There's a guy who still sells those on eBay. They're BIN @ $175.00
    >> but I need a punch as well and I only have serial ports and his unit
    >> uses a parallel port.

    >
    > That seems pretty expensive to me. The one I remember was mostly
    > just the phototransistors and buffers, and latches the data on
    > the index hole.


    Yes but for those of us who couldn't build our own if our life depended
    on it, $175 is reasonable for a device that provides a needed capability.

    Tom Lake

+ Reply to Thread
Page 2 of 3 FirstFirst 1 2 3 LastLast