[HECnet] Drives for a VAX-11/730

[Kari Uusim ki]

There has been a SA7x rackmount enclosure for RA7x disks. About the same size as RA9x enclosures. Very similar to SF7x enclosures.
I think you could find SA7x's from the large brokers who have old DEC hardware for sale. I guess the pricing would be reasonable.


Kari



On 15.7.2013 17:21, Bob Armstrong wrote:
    My 11/730 is not happy     the electronics work great and are even
fairly easy to fix, but keeping disk drives on the thing working is
proving to be a challenge.   Right now it has two RA81s and one has quit
completely (   servo fine position error   ) and the other is flaky.   The
original R80 on the RB730 had the HDA die years ago and I   ve never been
able to find a replacement.

    I have several vintage SMD drives, including a couple of nice CDC
9715 drives, that I was thinking about using to replace the RA8x
drives.   I have not one but two UNIBUS SMD controllers     an Emulex SC21
and a Spectra Logic 121     that I thought would do the job, but after
reading the fine print yesterday that turns out not to be true.   Both
controllers emulate RH11s with RM0x drives attached, which is fine if
you   re a PDP-11 but VMS has never supported that configuration.

    [Before anybody says    Wait     RM05s are supported by VMS,    that   s only
partly true.   VMS supported MASSBUS disks on a RH750 or RH780
controller, but VMS has never supported the RH11.   Emulex actually sold
a special VMS driver for their card, but I don   t have it and besides,
VMB still wouldn   t support it.   The Spectra Logic manual only talks
about PDP-11 OSes and carefully avoids ever mentioning VMS.]

    I   ve got some RA7x drives, but there   s no easy way to mount them or
supply power to them.   I   m not sure if there ever was a rack mount
chassis for RA7x drives.   There was for RA9x drives, but those I don   t
have.     I also have two RC25 drives and several AZTEC controllers, but
those drives were horribly unreliable even when they were new.   Neither
works, and fixing them or getting removable media for them is hopeless.

    Does anybody have any other ideas?   Who else has an old UNIBUS VAX?
What are you doing to disk drives?

    I   ve actually had the 11/730 for about fifteen years now     I restored
it out of parts from two different 730s that were scrapped.   It   s been
fairly easy to keep running except for the drives, and although it   s
admittedly a bit slow, it   s a cool machine.

Bob