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Re: Update on my Altair

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  • W Tom
    Pertec was an innovator is sheet metal technology, so perhaps the drives were innovative, not cheesy. A three point is required to avoid flex in the case
    Message 1 of 21 , Jun 11, 2013
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      Pertec was an innovator is sheet metal technology, so perhaps the drives
      were innovative, not cheesy. A three point is required to avoid flex in
      the case changing alignment. A three point mount means three mounting
      screws only. It does not mean no support on one corner. I found one
      drive chassis that had wire tied to the drive to support the back
      corner.

      I've found a few drives that can read each others diskettes and old ones
      too. Not all old drives need alignment.

      I do hope someone makes a How to Align video. I like the idea the
      process requires a hammer and would like to see it recorded. I've heard
      two warnings from engineer friends. The first is don't loosen the screws
      too much. The second is beware that the last person did not loosen the
      screws enough. Bent screws make the next alignment difficult.

      Different controller versions are software compatible. There was a
      timing modification documented September 2, 1977:

      "To increase diskette interchangeability from drive to drive and
      minimize Disk I/O errors, we have re-evaluated two time constants on the
      88-DCDD Controller Board #1. The effect of the timing change is to
      center the data within the sector to allow a greater tolerance of Disk
      Drive misalignment"

      Newer diskettes are supposed to labeled "NWD". MITS Diskettes made
      before August 31. 1977 use the old timing.

      I'll have the documents scanned. Procedures include board modification
      and converting diskettes.

      Tom S.



      --- In altaircomputerclub@yahoogroups.com, "tkaragiris" wrote:
      >
      > Ok, I'll keep that in mind. I'll work through the alignment procedure
      as far as I can. I find with a lot of the hardware related technical
      stuff, that I'm not a natural at, if I persevere with it long enough it
      eventually makes sense.
      >
      >
      >
      > --- In altaircomputerclub@yahoogroups.com, "mfeberhard" eberhard@
      wrote:
      > >
      > > There have been a couple of revisions of the controller boards. As
      far as I know, they are software-compatible. MITS was just trying to get
      them to be more reliable. I bet others here know more about the
      differences in controller revisions than I do.
      > >
      > > As far as alignment goes - I tried the same thing you are
      suggesting: clean up the drives, follow the MITS manual setup procedure,
      and hope for the best :-) In my case, 6 out of 6 drives required
      alignment. All but one were pretty good regarding the CE alignment
      (track placement on the diskette), but the index sensors were all over
      the map. (The last one had a broken head-load pad arm, requiring me to
      disassemble the whole head assembly.)
      > >
      > > When they were out of alignment, they "kind of worked," which I find
      most irritating. These drives would be able to read any diskette that
      had been written on the same drive. And they would sometimes be able to
      read diskettes written on other people's drives. If I wrote anything
      onto one of the diskettes that I got from others, then that diskette
      would become even more unreliable.
      > >
      > > But this was sporadic, sometimes they seemed to work just fine, for
      a little while. I wasted a lot of time chasing non-problems on my
      controllers, until I figured out that it was really an alignment
      problem.
      > >
      > > -Martin E
      > >
      > > --- In altaircomputerclub@yahoogroups.com, "tkaragiris" wrote:
      > > >
      > > > Martin,
      > > >
      > > > Ok thanks for that. 1,2 & 3 I should have no problem with, I'll
      start inspecting the mechanical side before I attempt to insert a disk.
      The
      > > > head alignment part I'm not too sure about, but I'll see how I go.
      > > >
      > > > > Mike (deramp5113) wrote a really nice little exerciser program
      for
      > > > > the 88-DVDD. It lets you seek tracks, step in and out, and
      > > > > load/unload the head. You should get a copy of this from him -
      it
      > > > > will help you do these adjustments. You should also look at his
      > > > > PC2FLOP software. It is awesome for creating Altair disks from
      files
      > > > > on your PC.
      > > >
      > > > This sounds good, if I could at least get my drive to load/unload
      the head before proceeding with anything else, that would confirm that
      my controllers are working with the drive. As the controllers and the
      drive came from two different sources, I'm hoping that they will work
      together.
      > > >
      > > > I've heard there were a few different revisions of the disk
      controllers so I'm not sure what effect that has on the drive?
      > > >
      > > > Thanks for the offer of the boot disks, I'm hoping that if the
      mechanics of the drive look ok, I'll just try one and see what happens.
      > > >
      > > > Thanks,
      > > > Theo
      > > >
      > >
      >
    • tkaragiris
      Mike, Success! I used the paper tape loader and image and set byte 12 to 176, worked like a charm. I can now load Disk Extended Basic. Finally, I used the
      Message 2 of 21 , Jun 11, 2013
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        Mike,

        Success!

        I used the paper tape loader and image and set byte 12 to 176, worked like a charm. I can now load Disk Extended Basic. Finally, I used the backspace key in Basic!

        Curious though that my attempts to load it via the serial bin loader using the .bin image didn't work. It worked for all the others. In any case using the tape image is just as good.

        Thanks again!

        --- In altaircomputerclub@yahoogroups.com, "deramp5113" <deramp5113@...> wrote:
        > Note, however, that the octal byte at location 012 in the 2SIO
        > bootstrap loader should be octal 176 for extended disk basic 5.0,
        > not octal 77 as shown in the BASIC manual. Also, "normal" extended
        > basic does not support the disk drive.
      • tkaragiris
        I ve got two sets of disk controllers, they are both marked with the same revision numbers. One set has some battery acid damage on them, I suspect they won t
        Message 3 of 21 , Jun 11, 2013
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          I've got two sets of disk controllers, they are both marked with the same revision numbers.  One set has some battery acid damage on them, I suspect they won't even work.  But the other set came from the same Altair BT as my 88-2SIO.  That set seems in fairly good condition.

          The boards are marked:

          - MITS DISK BD 1 REV 0-X3
          - MITS DISK #2 REV 0-X2

          I'll install these in the Altair tomorrow and try and get some life signs from the disk drive.

          I took some high res pictures of the better set of disk controller boards. They're on my site here:

          MITS disk controller 



        • deramp5113
          Great! Where in memory is your serial .bin loader? To load Disk BASIC, it would need to be pretty high in memory - put it at 0x8000 or above. Mike
          Message 4 of 21 , Jun 11, 2013
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            Great!

            Where in memory is your serial .bin loader? To load Disk BASIC, it would need to be pretty high in memory - put it at 0x8000 or above.

            Mike

            --- In altaircomputerclub@yahoogroups.com, "tkaragiris" <tkaragiris@...> wrote:
            >
            > Mike,
            >
            > Success!
            >
            > I used the paper tape loader and image and set byte 12 to 176, worked like a charm. I can now load Disk Extended Basic. Finally, I used the backspace key in Basic!
            >
            > Curious though that my attempts to load it via the serial bin loader using the .bin image didn't work. It worked for all the others. In any case using the tape image is just as good.
            >
            > Thanks again!
            >
            > --- In altaircomputerclub@yahoogroups.com, "deramp5113" <deramp5113@> wrote:
            > > Note, however, that the octal byte at location 012 in the 2SIO
            > > bootstrap loader should be octal 176 for extended disk basic 5.0,
            > > not octal 77 as shown in the BASIC manual. Also, "normal" extended
            > > basic does not support the disk drive.
            >
          • Stuart Wyatt
            What I remember the most about fighting drive alignment was even the slightest amount of tightening/loosening of the head stepper motor screws would send the
            Message 5 of 21 , Jun 11, 2013
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              What I remember the most about fighting drive alignment was even the slightest amount of tightening/loosening of the head stepper motor screws would send the timing flying off the scope.  It was the classic problem of trying to clamp something in place with a bolt an expecting it not to move when you tightened the bolt.

               

              Am I the only one that had this issue with the head motor “mount”?  I hear a lot about the drive mounting itself, but for us that was nothing compared to the head motor mounts.  Was there some trick I missed?  I dread the idea of trying to align them again.

               

              -Stuart

              From: altaircomputerclub@yahoogroups.com [mailto:altaircomputerclub@yahoogroups.com] On Behalf Of W Tom

              Pertec was an innovator is sheet metal technology, so perhaps the drives
              were innovative, not cheesy. A three point is required to avoid flex in
              the case changing alignment. A three point mount means three mounting
              screws only. It does not mean no support on one corner. I found one
              drive chassis that had wire tied to the drive to support the back
              corner.

              I've found a few drives that can read each others diskettes and old ones
              too. Not all old drives need alignment.

              I do hope someone makes a How to Align video. I like the idea the
              process requires a hammer and would like to see it recorded. I've heard
              two warnings from engineer friends. The first is don't loosen the screws
              too much. The second is beware that the last person did not loosen the
              screws enough. Bent screws make the next alignment difficult.

              Different controller versions are software compatible. There was a
              timing modification documented September 2, 1977:

              "To increase diskette interchangeability from drive to drive and
              minimize Disk I/O errors, we have re-evaluated two time constants on the
              88-DCDD Controller Board #1. The effect of the timing change is to
              center the data within the sector to allow a greater tolerance of Disk
              Drive misalignment"

              Newer diskettes are supposed to labeled "NWD". MITS Diskettes made
              before August 31. 1977 use the old timing.

              I'll have the documents scanned. Procedures include board modification
              and converting diskettes.

              Tom S.

              --- In altaircomputerclub@yahoogroups.com, "tkaragiris" wrote:
              >
              > Ok, I'll keep that in mind. I'll work through the alignment procedure
              as far as I can. I find with a lot of the hardware related technical
              stuff, that I'm not a natural at, if I persevere with it long enough it
              eventually makes sense.
              >
              >
              >
              > --- In altaircomputerclub@yahoogroups.com, "mfeberhard" eberhard@
              wrote:
              > >
              > > There have been a couple of revisions of the controller boards. As
              far as I know, they are software-compatible. MITS was just trying to get
              them to be more reliable. I bet others here know more about the
              differences in controller revisions than I do.
              > >
              > > As far as alignment goes - I tried the same thing you are
              suggesting: clean up the drives, follow the MITS manual setup procedure,
              and hope for the best :-) In my case, 6 out of 6 drives required
              alignment. All but one were pretty good regarding the CE alignment
              (track placement on the diskette), but the index sensors were all over
              the map. (The last one had a broken head-load pad arm, requiring me to
              disassemble the whole head assembly.)
              > >
              > > When they were out of alignment, they "kind of worked," which I find
              most irritating. These drives would be able to read any diskette that
              had been written on the same drive. And they would sometimes be able to
              read diskettes written on other people's drives. If I wrote anything
              onto one of the diskettes that I got from others, then that diskette
              would become even more unreliable.
              > >
              > > But this was sporadic, sometimes they seemed to work just fine, for
              a little while. I wasted a lot of time chasing non-problems on my
              controllers, until I figured out that it was really an alignment
              problem.
              > >
              > > -Martin E
              > >
              > > --- In altaircomputerclub@yahoogroups.com, "tkaragiris" wrote:
              > > >
              > > > Martin,
              > > >
              > > > Ok thanks for that. 1,2 & 3 I should have no problem with, I'll
              start inspecting the mechanical side before I attempt to insert a disk.
              The
              > > > head alignment part I'm not too sure about, but I'll see how I go.
              > > >
              > > > > Mike (deramp5113) wrote a really nice little exerciser program
              for
              > > > > the 88-DVDD. It lets you seek tracks, step in and out, and
              > > > > load/unload the head. You should get a copy of this from him -
              it
              > > > > will help you do these adjustments. You should also look at his
              > > > > PC2FLOP software. It is awesome for creating Altair disks from
              files
              > > > > on your PC.
              > > >
              > > > This sounds good, if I could at least get my drive to load/unload
              the head before proceeding with anything else, that would confirm that
              my controllers are working with the drive. As the controllers and the
              drive came from two different sources, I'm hoping that they will work
              together.
              > > >
              > > > I've heard there were a few different revisions of the disk
              controllers so I'm not sure what effect that has on the drive?
              > > >
              > > > Thanks for the offer of the boot disks, I'm hoping that if the
              mechanics of the drive look ok, I'll just try one and see what happens.
              > > >
              > > > Thanks,
              > > > Theo
              > > >
              > >
              >

            • corey986
              Curious, Have you tried loading the 4k and 8k basic (version 4.0 and higher) using the paper tape images or the bin images only. I m trying to figure out
              Message 6 of 21 , Jun 11, 2013
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                Curious,

                Have you tried loading the 4k and 8k basic (version 4.0 and higher) using the paper tape images or the bin images only. I'm trying to figure out which is more reliable.

                Cheers,
                Corey

                --- In altaircomputerclub@yahoogroups.com, "tkaragiris" <tkaragiris@...> wrote:
                >
                > Mike,
                >
                > Success!
                >
                > I used the paper tape loader and image and set byte 12 to 176, worked like a charm. I can now load Disk Extended Basic. Finally, I used the backspace key in Basic!
                >
                > Curious though that my attempts to load it via the serial bin loader using the .bin image didn't work. It worked for all the others. In any case using the tape image is just as good.
                >
                > Thanks again!
                >
                > --- In altaircomputerclub@yahoogroups.com, "deramp5113" <deramp5113@> wrote:
                > > Note, however, that the octal byte at location 012 in the 2SIO
                > > bootstrap loader should be octal 176 for extended disk basic 5.0,
                > > not octal 77 as shown in the BASIC manual. Also, "normal" extended
                > > basic does not support the disk drive.
                >
              • mfeberhard
                There s a technique to tightening those motor mount bolts so as not to knock the alignment (much). The rear bolts have fiber washers that make it possible to
                Message 7 of 21 , Jun 11, 2013
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                  There's a technique to tightening those motor mount bolts so as not to knock the alignment (much). The rear bolts have fiber washers that make it possible to move the actuator assembly when these bolts are partially tightened.

                  The trick is to loosen the front bolts, and just loosen the rear ones a tad. you can then move the actuator assembly by inserting a screwdriver between the motor and the sheet metal frame, and prying gently with the screwdriver. (This works particularly well for the touchy side-to-side adjustment.)

                  When the alignment's right, tighten the front bolts lightly, then tighten the rear bolts snugly, then tighten the front ones snugly.

                  I've done this while watching the pattern from an alignment disk, and the alignment barely moves as I tightened the actuator assembly in place.

                  -Martin

                  --- In altaircomputerclub@yahoogroups.com, Stuart Wyatt <stuart@...> wrote:
                  >
                  > What I remember the most about fighting drive alignment was even the slightest amount of tightening/loosening of the head stepper motor screws would send the timing flying off the scope. It was the classic problem of trying to clamp something in place with a bolt an expecting it not to move when you tightened the bolt.
                  >
                  > Am I the only one that had this issue with the head motor "mount"? I hear a lot about the drive mounting itself, but for us that was nothing compared to the head motor mounts. Was there some trick I missed? I dread the idea of trying to align them again.
                  >
                  > -Stuart
                • Stuart Wyatt
                  That sounds like the trick I was missing! Thanks! You just moved me much closer to wanting to turn them on again, knowing I d likely have to align them.
                  Message 8 of 21 , Jun 11, 2013
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                    That sounds like the trick I was missing!  Thanks!  You just moved me much closer to wanting to turn them on again, knowing I’d likely have to align them.

                     

                    -Stuart

                     

                    From: altaircomputerclub@yahoogroups.com [mailto:altaircomputerclub@yahoogroups.com] On Behalf Of mfeberhard
                    Sent: Tuesday, June 11, 2013 7:49 AM
                    To: altaircomputerclub@yahoogroups.com
                    Subject: [Altair Computer Club] Re: Update on my Altair

                     

                     

                    There's a technique to tightening those motor mount bolts so as not to knock the alignment (much). The rear bolts have fiber washers that make it possible to move the actuator assembly when these bolts are partially tightened.

                    The trick is to loosen the front bolts, and just loosen the rear ones a tad. you can then move the actuator assembly by inserting a screwdriver between the motor and the sheet metal frame, and prying gently with the screwdriver. (This works particularly well for the touchy side-to-side adjustment.)

                    When the alignment's right, tighten the front bolts lightly, then tighten the rear bolts snugly, then tighten the front ones snugly.

                    I've done this while watching the pattern from an alignment disk, and the alignment barely moves as I tightened the actuator assembly in place.

                    -Martin

                    --- In altaircomputerclub@yahoogroups.com, Stuart Wyatt <stuart@...> wrote:
                    >
                    > What I remember the most about fighting drive alignment was even the slightest amount of tightening/loosening of the head stepper motor screws would send the timing flying off the scope. It was the classic problem of trying to clamp something in place with a bolt an expecting it not to move when you tightened the bolt.
                    >
                    > Am I the only one that had this issue with the head motor "mount"? I hear a lot about the drive mounting itself, but for us that was nothing compared to the head motor mounts. Was there some trick I missed? I dread the idea of trying to align them again.
                    >
                    > -Stuart

                  • deramp5113
                    Corey, If you re downloading the .bin or tape images directly from a PC, either way is just as reliable. You re not going to have data transmission errors even
                    Message 9 of 21 , Jun 11, 2013
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                      Corey,

                      If you're downloading the .bin or tape images directly from a PC, either way is just as reliable. You're not going to have data transmission errors even at 9600 baud across a ten foot cable.

                      One "advantage" the tape load provides is that it does verify the data gets written to memory. This may catch a memory issue in your computer one day.

                      Mike


                      --- In altaircomputerclub@yahoogroups.com, corey986 <no_reply@...> wrote:
                      >
                      > Curious,
                      >
                      > Have you tried loading the 4k and 8k basic (version 4.0 and higher) using the paper tape images or the bin images only. I'm trying to figure out which is more reliable.
                      >
                      > Cheers,
                      > Corey
                      >
                      > --- In altaircomputerclub@yahoogroups.com, "tkaragiris" <tkaragiris@> wrote:
                      > >
                      > > Mike,
                      > >
                      > > Success!
                      > >
                      > > I used the paper tape loader and image and set byte 12 to 176, worked like a charm. I can now load Disk Extended Basic. Finally, I used the backspace key in Basic!
                      > >
                      > > Curious though that my attempts to load it via the serial bin loader using the .bin image didn't work. It worked for all the others. In any case using the tape image is just as good.
                      > >
                      > > Thanks again!
                      > >
                      > > --- In altaircomputerclub@yahoogroups.com, "deramp5113" <deramp5113@> wrote:
                      > > > Note, however, that the octal byte at location 012 in the 2SIO
                      > > > bootstrap loader should be octal 176 for extended disk basic 5.0,
                      > > > not octal 77 as shown in the BASIC manual. Also, "normal" extended
                      > > > basic does not support the disk drive.
                      > >
                      >
                    • tkaragiris
                      Corey, I ve now loaded all versions of Basic from 4k v3.2 up, using both tape and bin images through Tera Term. Both work as reliably as each other. The only
                      Message 10 of 21 , Jun 11, 2013
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                        Corey,

                        I've now loaded all versions of Basic from 4k v3.2 up, using both tape and bin images through Tera Term. Both work as reliably as each other. The only exception being Disk Extended Basic (25k file) not loading via the bin image, using the bin serial loader.

                        I checked the bin serial loader that I use and it loads at 3f80H, which is around the 16k mark so that's why I could never get that version to load via the .bin loader. Because it was overwriting the loader program.

                        In any case the tape image loads if I use the correct flag at byte 12: 176 (oct).

                        What Mike says makes sense though, that the tape load actually does checks as it loads whereas the bin load does not. So stands to reason the tape loader would be more reliable.


                        --- In altaircomputerclub@yahoogroups.com, corey986 <no_reply@...> wrote:
                        >
                        > Curious,
                        >
                        > Have you tried loading the 4k and 8k basic (version 4.0 and higher) using the paper tape images or the bin images only. I'm trying to figure out which is more reliable.
                        >
                        > Cheers,
                        > Corey
                        >
                        > --- In altaircomputerclub@yahoogroups.com, "tkaragiris" <tkaragiris@> wrote:
                        > >
                        > > Mike,
                        > >
                        > > Success!
                        > >
                        > > I used the paper tape loader and image and set byte 12 to 176, worked like a charm. I can now load Disk Extended Basic. Finally, I used the backspace key in Basic!
                        > >
                        > > Curious though that my attempts to load it via the serial bin loader using the .bin image didn't work. It worked for all the others. In any case using the tape image is just as good.
                        > >
                        > > Thanks again!
                        > >
                        > > --- In altaircomputerclub@yahoogroups.com, "deramp5113" <deramp5113@> wrote:
                        > > > Note, however, that the octal byte at location 012 in the 2SIO
                        > > > bootstrap loader should be octal 176 for extended disk basic 5.0,
                        > > > not octal 77 as shown in the BASIC manual. Also, "normal" extended
                        > > > basic does not support the disk drive.
                        > >
                        >
                      • tkaragiris
                        Yeah, that was the problem with the serial bin loader. It loads at 3f80H, 16k mark, and it was getting overwritten by the 25k Basic file. That s why all the
                        Message 11 of 21 , Jun 11, 2013
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                          Yeah, that was the problem with the serial bin loader. It loads at 3f80H, 16k mark, and it was getting overwritten by the 25k Basic file. That's why all the others worked ok.


                          --- In altaircomputerclub@yahoogroups.com, "deramp5113" <deramp5113@...> wrote:
                          >
                          > Great!
                          >
                          > Where in memory is your serial .bin loader? To load Disk BASIC, it would need to be pretty high in memory - put it at 0x8000 or above.
                          >
                          > Mike
                          >
                          > --- In altaircomputerclub@yahoogroups.com, "tkaragiris" <tkaragiris@> wrote:
                          > >
                          > > Mike,
                          > >
                          > > Success!
                          > >
                          > > I used the paper tape loader and image and set byte 12 to 176, worked like a charm. I can now load Disk Extended Basic. Finally, I used the backspace key in Basic!
                          > >
                          > > Curious though that my attempts to load it via the serial bin loader using the .bin image didn't work. It worked for all the others. In any case using the tape image is just as good.
                          > >
                          > > Thanks again!
                          > >
                          > > --- In altaircomputerclub@yahoogroups.com, "deramp5113" <deramp5113@> wrote:
                          > > > Note, however, that the octal byte at location 012 in the 2SIO
                          > > > bootstrap loader should be octal 176 for extended disk basic 5.0,
                          > > > not octal 77 as shown in the BASIC manual. Also, "normal" extended
                          > > > basic does not support the disk drive.
                          > >
                          >
                        • steve
                          Martin- That s exactly how I did it at MITS. You was supposed to bang on the handle of a screwdriver with your official hammer (a small mallet with both a
                          Message 12 of 21 , Jun 11, 2013
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                            Martin-

                            That's exactly how I did it at MITS.

                            You was supposed to bang on the handle of a screwdriver with your official hammer (a small mallet with both a plastic and a rubber face. At MITS, it was issued as part of their general tech toolkit), which would impact on the motor mounts and (preferably) cause the head motor to slip in its still-tight mount, or (usually) it would bend the mounting bolt, or both. This was really stupid, because once a bolt was bent, the next alignment would be much more difficult. When aligning old or previously aligned drives, I made it a habit to install new replacement bolts to insure straightness. They were snugged but not tightened, and I only torqued them down as the final step. Sometimes a light tap with a screwdriver handle was quicker and easier than prying with a screwdriver, but anything more drastic was unnecessary if you did it right.

                            The FD4xx/5xx frame was a welded 3-piece sheet metal thing that was not in the same class as the cast aluminum frames of Shugart's 8" drives. I worked on hundreds the Pertec drives back then, and saw every problem mentioned so far in this thread. They were springy/flexy/bendy. However, I think they were also the least expensive by far, which made them very attractive to hobbyists and to Ed Roberts.

                            ===========================================

                            --- In altaircomputerclub@yahoogroups.com, "mfeberhard" <eberhard@...> wrote:
                            >
                            > There's a technique to tightening those motor mount bolts so as not to knock the alignment (much). The rear bolts have fiber washers that make it possible to move the actuator assembly when these bolts are partially tightened.
                            >
                            > The trick is to loosen the front bolts, and just loosen the rear ones a tad. you can then move the actuator assembly by inserting a screwdriver between the motor and the sheet metal frame, and prying gently with the screwdriver. (This works particularly well for the touchy side-to-side adjustment.)
                            >
                            > When the alignment's right, tighten the front bolts lightly, then tighten the rear bolts snugly, then tighten the front ones snugly.
                            >
                            > I've done this while watching the pattern from an alignment disk, and the alignment barely moves as I tightened the actuator assembly in place.
                            >
                            > -Martin
                            >
                            > --- In altaircomputerclub@yahoogroups.com, Stuart Wyatt <stuart@> wrote:
                            > >
                            > > What I remember the most about fighting drive alignment was even the slightest amount of tightening/loosening of the head stepper motor screws would send the timing flying off the scope. It was the classic problem of trying to clamp something in place with a bolt an expecting it not to move when you tightened the bolt.
                            > >
                            > > Am I the only one that had this issue with the head motor "mount"? I hear a lot about the drive mounting itself, but for us that was nothing compared to the head motor mounts. Was there some trick I missed? I dread the idea of trying to align them again.
                            > >
                            > > -Stuart
                            >
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