[SPAM] - Re: Simulated disk drive for RT-11? - Sending mail serverfound on relays.ordb.org

[Allison]

>
>Subject: Re: [SPAM] - Re: Simulated disk drive for RT-11? - Sending mail serverfound on relays.ordb.org
>   From: "Jerome H. Fine" <jhfinexgs2 at compsys.to>
>   Date: Wed, 08 Jun 2005 22:05:18 -0400
>     To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org>
>
> >Allison wrote:
>
>>>Jerome Fine replies:
>>>That would explain the situation since no one else seems
>>>to have ever seen a pure Q22 backplane for a BA23.
>>>
>>It's possible, I've done it and it fits well.  The Q22
>>18slot (M9275) is a nice backplane for non-PMI based 
>>systems.
>>
>Jerome Fine replies:
>
>If you want to add one more backplane to your
>list, I used a 2 * 22 slot Qbus Q22 bit backplane
>when I did some Y2K bug fixes for some application
>programs.  Specifically, this was a 22 slot backplane
>with ONLY dual slots, obviously all AB.  The last slot
>had extra room to allow for a board of about 2" that
>held a small SCSI hard drive of about 100 MBytes.
>The 3rd last slot (and the 2nd last which it overlapped)
>help a 3 1/2" floppy or an RX23.  There was a CQD 220/TM
>with special ROMs which supported the RX23 as a standard
>device with removable media.  By the way, the power
>supply was not part of the box holding the backplane -
>they (power supply and backplane) were connected by a
>short 3 foot cable.  I think that the ONLY  DEC board
>was the M8192-YB CPU.

I've seen one of them, third party nonDEC.  The 12 slot is fine 
as a 11/23 board set and a meg of ram with RQDX3 it can hold 
everything needed except power.


>As for one more backplane, I presume that you have the
>4 * 4 slot (4 quad slots) for the VT103 which were sold
>with 18 bits, but could be upgraded in the field to 22
>bits.  At one point, I heard that someone made the first
>2 slots AB / CD and installed a uVAX-II.  That was beyond
>my ability, I only used an M8190-BB and a 4 MByte memory
>board with a CDQ 220/TM and a DHQ11.

I have two.  One modded for Q22 and the other Q22/ 2slotsCD.
That was a had discussed internally at DEC.  There were a 
few made.

>Those days fooling with the hardware were fun, but now
>that there are emulators that can run about 100 times
>the speed of a PDP-11/73, for an RT-11 software addict
>like myself, the hardware has become much less important.

Doesn't work for me.  Sims are useful but the fastest PC I have
is a 1g celeron.  They aren't that fast and often a lot less 
reliable as the OS supporting them can be cranky.

I still have two xerox paper boxes full of Qbus cards, hardware
is easy.

Allison