Allison ajp166 at
Thu Nov 17 17:21:35 CST 2005

>Subject: Re: Minix
>   From: woodelf <bfranchuk at>
>   Date: Thu, 17 Nov 2005 15:19:04 -0700
>     To: General Discussion: On-Topic and Off-Topic Posts <cctalk at>
>Allison wrote:
>><sarcasm warning>
>>And you want it delivered configured for free.
>yes !  Free is good.
>I even want it shipped.

ah, reading impaired?

>But say other than ebay ( something I can't use because stupid scammers 
>my email address ) how much is a  PDP - 11 cpu, dual serial card, 64kb 
>of memory
>and working mass storage that can be reasionable shipped?
>PS and even a power supply and bootstrap rom . Front panel is not needed.

Ok it's very obvious you know nothing of PDP-11s.  First, 64kb of memory.
PDP11s have memory mapped IO so the TOP 8kb of memory is IO space.  Typically
a loaded PDP11 without MMU is 24-28kW of ram (words as its a 16bitter).

Now with all that been said about models, boards and busses.  You expressed 
no wish other "I want one.".  Well lets all drop a 11/70 mid sized system on
you.  Figure about 500 pounds and 3 6ft racks plus a few washing machine 
sized disks. Got a spare room with air conditioning. Don't forget you 
need a 220V 30A drop for that.

Oh, too big.  Ok how about an microPDP11 on about 30" deep, 27" tall and 
8" wide. Runs on 120V maybe 4-5a max.  Oh weighs in around 60pounds with 
a single hard disk of 30mb. Should easily cost more to ship than buy. 
Shipping will cost a bomb due to both size and weight.  The disk should 
be removed and packed seperately. Not a lot of those around but a great find.

Next down is a BA-11VA box about 4x11x13" and only four bual width slots.
 Shipable and likely cheap.  The trick is using a 11/23 cpu, MXV11 and MRV11
to get over 256k of ram, two serial ports and boot roms in three boards.  
Of course theres still no mass storage and RX02 is abou 50 pound rack 
mount or at least table top sized.  The RQDX3 is an other one board 
solution but the BA11VA doesnt support a distribution board or power 
for the drives so it's not easily used.  RL02 is a quad width, not 
usable in that box.  Maybe too small a box.

So thats cheap and common usually the BAll-S. Recognizable by the three 
toggle switches on the front. had plenty of bus and power for most Qbus
boards.  No disk bays and generally meant for rack mounting. So usually 
you want one of these in a rack of the 48" or taller.  Then disks like 
RX02 and RL02 are easily mounted. Not shippable except by freight. The 
good news is of all PDP11s they are most common and often free.  Try 
your local university.

Can't give cost for a reason, soon as you ask the price is what traffic 
will support.  Suppliers exist for used DEC boards and systems. Prices 
are what they are.  

Local to me, (less than 10 miles from DEC home central) aka, 
The Greater Maynard Area PDP11 systems are common, and usually 
free if you haul. 


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