ra disks - VMS

This is a discussion on ra disks - VMS ; Hi, Just wanting to get a reliable mass storage device going for the old 11/73. Can the ra-series disks be interfaced easily? Will 2.11 BSD be happy with them? Anyone have a large number of them available cheap? thanks jake...

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  1. ra disks

    Hi,
    Just wanting to get a reliable mass storage device going for the
    old 11/73. Can the ra-series disks be interfaced easily? Will 2.11
    BSD be happy with them? Anyone have a large number of them available
    cheap?

    thanks
    jake


  2. Re: ra disks

    In article <1116896801.008436.16900@g44g2000cwa.googlegroups.c om>,
    jacob.ritorto@gmail.com wrote:
    > Just wanting to get a reliable mass storage device going for the
    >old 11/73. Can the ra-series disks be interfaced easily?


    Yes. All you need is a KDA50 and associated cab kit.

    >Will 2.11
    >BSD be happy with them?


    Yes; they just show up as MSCP devices.

    Note that I couldn't really run an RA80 in my apartment without blowing
    fuses.

    --
    David Evans
    Faculty of Computer Science dfevans@bbcr.uwaterloo.ca
    Dalhousie University, Halifax, Canada http://bbcr.uwaterloo.ca/~dfevans/

  3. Re: ra disks

    > old 11/73. Can the ra-series disks be interfaced easily?

    Pretty much. The one gotcha is that the KDA50 board set sucks up a lot
    of power. Officially, if you have a single BA23 backplane, it's not
    supported because of power demands.Unofficially, if you don't have much
    other than CPU, memory, and disk controller, you can probably squeak
    by. Otherwise you can use a second BA23.

    The BA123 and BA213 boxes aren't quite so power-starved, but you still
    have to look at total current draw.

    I highly advise the RA9x or RA7x over the RA8x. Reliability-wise, I
    think the RA9x are supreme, but they're a lot bigger and heavier than a
    RA7x.

    Tim.


  4. Re: ra disks

    In article <1116935181.824047.67950@o13g2000cwo.googlegroups.c om>,
    "Tim Shoppa" writes:
    >> old 11/73. Can the ra-series disks be interfaced easily?

    >
    > Pretty much. The one gotcha is that the KDA50 board set sucks up a lot
    > of power. Officially, if you have a single BA23 backplane, it's not
    > supported because of power demands.Unofficially, if you don't have much
    > other than CPU, memory, and disk controller, you can probably squeak
    > by. Otherwise you can use a second BA23.
    >
    > The BA123 and BA213 boxes aren't quite so power-starved, but you still
    > have to look at total current draw.
    >
    > I highly advise the RA9x or RA7x over the RA8x. Reliability-wise, I
    > think the RA9x are supreme, but they're a lot bigger and heavier than a
    > RA7x.
    >


    As long as you've brought it up, anybody have any RA7x or RA9x disks
    they don't need that they would like to donate to my PDP-11 EDU project?
    I now have licenses and expect to have RSX, RSTS and RT-11 available
    for student use for the fall semester. The only thing I am working
    on is disks space. I had a UNIBUS SCSI Controller donated by Colin
    Butcher (greatly appreciated!) but I do still have a couple of UDA50
    and KDA50 controllers so if I can find reasonable disks I can use them
    as well. (I got rid of all my RA8x disks. Keeping them running was
    becoming a problem and hardly worth the power they consumed.)

    bill

    --
    Bill Gunshannon | de-moc-ra-cy (di mok' ra see) n. Three wolves
    bill@cs.scranton.edu | and a sheep voting on what's for dinner.
    University of Scranton |
    Scranton, Pennsylvania | #include

  5. Re: ra disks

    Tim Shoppa wrote:
    >>old 11/73. Can the ra-series disks be interfaced easily?

    >
    >
    > Pretty much. The one gotcha is that the KDA50 board set sucks up a lot
    > of power.


    ABout 13 amps a 5 volts memory. One of the many MSCP controllers
    with SCSI interfaces would be a better choice

  6. Re: ra disks

    jacob.ritorto@gmail.com wrote:
    > Just wanting to get a reliable mass storage device going for the
    > old 11/73. Can the ra-series disks be interfaced easily? Will 2.11
    > BSD be happy with them? Anyone have a large number of them available
    > cheap?


    Yes, the RA series work with a QDA50 interface, which
    speaks MSCP protocol over the Qbus. Most "late"
    versions of OSes should support MSCP disks. One eBay
    vendor periodically offers an intact rack of RAs
    (some DEC nomenclature starting with "SA" for "Storage
    Array") for something like $295 plus shipping from
    California; I think he may have more than one of those
    SA racks available. If I had more room I would have
    snarfed it up before now.

    However, you might be better off using SCSI disks with
    an interface that speaks MSCP; there are several third-
    party cards that do that. SCSI disks are much more
    readily available and much smaller as well. You can
    mount several in a "PC" case and have the equivalent
    of an SA rack with a much smaller footprint and less
    power consumption.

  7. Re: ra disks

    Bill Gunshannon wrote:
    > As long as you've brought it up, anybody have any RA7x or RA9x disks
    > they don't need that they would like to donate to my PDP-11 EDU project?


    While Pat almost certainly wouldn't give them away for free,
    RELCOMSER seems to still have a large stock of RA71 and/or
    RA72 drives for sale cheap. I picked up a couple when I
    drove through IL a couple of years ago. Note that RA7x
    seems to have a different interface than RA8x.

  8. Re: ra disks

    Douglas A. Gwyn wrote:
    > QDA50 interface


    Oops, I meant KDA50-Q.

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