Simulated disk drive for RT-11?

[Allison]

>
>Subject: Re: Simulated disk drive for RT-11?
>   From: "Jerome H. Fine" <jhfinexgs2 at compsys.to>
>   Date: Mon, 06 Jun 2005 19:26:16 -0400
>     To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org>
>
> >Ethan Dicks wrote:
>
>>>On 6/6/05, Kevin Handy <kth at srv.net> wrote:
>>  
>>
>>>You could make one like DEC used to: Take an 8-slot backplane, and
>>>fill in four of the slots with epoxy. You now have a 4 slot backplane.
>>>    
>>>
>>Ahhhhgggg!  Ever seen that with a BA123?  Makes you cry... DEC didn't
>>want their graphical workstations being converted to departmental
>>server use, so they plugged up the extra holes in the backplane to
>>prevent expansion.  For a while, one could order a virgin backplane
>>from spares, but they eventually caught on (then they stopped hosing
>>workstation customers so much ;-)
>>
>>Fortunately, I've only ever seen it at a DECUS (DEC-owned demo
>>machines); none of the machines I've worked with or personally owned
>>were broken this way.
>>
>Jerome Fine replies:
>
>In the interest of proving that it was done (I
>suppose that this is NOT proof that DEC did the
>foul deed), I saved one of those backplanes from
>an old BA23 box.  As a matter of record, only the
>last 3 slots have epoxy.  If anyone wants the proof,
>I will save it for you since it is about time to
>toss it in the trash where it belongs.  By the way,
>as Antonio states below, this backplane is an 8 * 4
>slot from a BA23!!!!!!!!  Maybe Ethan's finger slipped
>and added an extra "1" after the "BA"?????????????
>I can't see that DEC would have converted a BA123,
>but I guess that DEC could have done anything at that.
>
>>Antonio Carlini wrote:
>
> >This was the (thankfully) short-lived VAXstation II/RC. The
> >one I saw came in a BA23, not a BA123. There were companies
> >around that would (allegedly) remove the epoxy (or whatever
> >it was they used) and hence restore full functionality.
>
>Just so I could say I tried, I once spent a few
>hours attempting to remove the epoxy - not a cost
>effective use of my time.  I suspect that these
>companies were more likely to have either purchased
>a replacement backplane or found a damaged BA23
>with a good backplane and removed the good backplane.

Thats what FS did!

Note there were differenet backplanes used in the BA23 those
that were compatable with uVAX-1, those that were uVAX-II
and the microPDP-11. Use the wrong one with the desired CPU
and bad results happen.

Allison