PDP 11/23 PLUS system for sale - test-drb@ccmp.vtda.org

15 Jun 2005

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Subject: RE: PDP 11/23 PLUS system for sale
   From: "Fred N. van Kempen" <waltje at pdp11.nl>
   Date: Wed, 15 Jun 2005 20:09:17 +0200 (MEST)
     To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at
classiccmp.org>

On Wed, 15 Jun 2005, Allison wrote:

  Actually depending on OS and general usage the
critical factor for
 the DEQNA was not rev but, is it functional at all?  Most of the
 DEQNAs I've touched and used either worked or were dead, rev was a
 minor issue save for certain OS support issues. I have about 20, and they're
all OK.  Screwy, but OK.

  One of the REV
 issues was that the more reworked versions tended to have more
 failures (IE plain old dead) resulting from greater amounts of
 handeling and use/abuse.  For Q-bus 11s the DEQNA was an
 acceptable device.  DELQAs while nicer were scarcer. I don't think that *now*,
DELQA's are scarcer.  They may have
been at the time, but not now. 
Nope.  DELQAs appeared as Qbus was becomming less common (AKA microVAXen)
and many of those when the DEQNA was retired it was because the uVAX 
had been too. Qbus uVAXen were often replaced by 3100s and other non-Q
systems. Field circus was also slow to replace them with DELQAs
unless the DEQNA had failed or was at issue for OS or other misfunctions.
Bluntly FS was cheap and one of the last profit centers.   By shear 
force of numbers there were never as many DELQAs as DEQNAs manufactured.  

Allison