[GreenKeys] 15-level tape

[Christian Gauger-Cosgrove]

Hello Tony and Greenkeyers interested in this conversation:

Here's a photo of my PDP-11 setup before I moved (and the fuckery that
ensued because of that move):
http://d.facdn.net/art/creideikistormbringer/1310739772.creideikistormbringer_pdp11-23_dsd880-8.png
Top is a BA11-N box (PDP-11/03 box); bottom is a DSD-880/8, which is a
combo of a DSDD 8" floppy drive* and an 8MB MFM disk drive**.


For those who want to see the guts of the machine:
http://d.facdn.net/art/creideikistormbringer/1309147636.creideikistormbringer_1123-backplane.png
For those who can't speak DEC QBUS board numbers:
> M8186 -- PDP-11/23 CPU card, with the memory management unit, and floating point processor
> M8059-KH -- 256KB of semiconductor RAM
> M8043 -- quadruple serial line interfaces
> M8049 -- quadruple 16-bit parallel interfaces
> M7555 -- RQDX3, MSCP based MFM harddisk and floppy diskette controller
> M9058 -- (To the right of RQDX3.) Cable distribution board for the RQDX3.
> Data Systems Design 808836 -- DSD 880/x Hard Disk & DSDD 8" Diskette Drive Controller
> MDB Systems Inc. MLSI-LP11 -- Printer interface
> M8012-YA -- 18-bit bus terminator with bootstrap and diagnostic ROMs

The machine cost myself nothing. A very generous member of Greenkeys
gave me the BA11-N box, and the majority of the boards within it. The
remainder I received with a VT-103 I traded for my (not very
functional) 33KSR. New, I'm unsure of the price.


Now to explain the two notes:
*: Those of you familiar with DEC hardware will be going "The hell? A
double-sided floppy drive?" as the standard DEC drives the RX01 and
RX02 were SSSD and SSDD respectively. Based on the driver sources of
RT-11 V4 there was apparently some work being on a DEC DSDD floppy
drive they termed the RX03. It never came to fruition, though the
RT-11 V4 diskette driver did still have the compiler options to be
built for DSDD drives. Some companies capitalized on this and produced
DSDD floppy drives for the PDP-11, DSD was one such company.
**: The 8MB MFM disk actually looks like an RL01 or RL02 to the
software. DSD's diskette drives, and their diskette+hard disk product
emulate the RXV21 diskette interface and RLV12 controller. On the
DSD-880/8 itself, the 8MB drive can either be set to respond as an
RL01 (which truncates the usable disk space to 5MB), or as an RL02
with significantly reduced space (8MB as opposed to 10MB; I believe it
did so by reporting a gigantic number of bad blocks).


Unfortunately, due to a really crappy move, I no longer own my PDP-11
system. I'm currently in the process of hopefully acquiring a "new"
one, though it is in a different chassis than the BA11-N boxed one.
(The "new" one is in a third party box equivalent to the BA11-N, and
was made here in Canada, so that's rather neat.)


Cheers,
Christian

On 15 January 2014 11:16, tony.podrasky <tony.podrasky at gmail.com> wrote:
> Hello Christian et al;
>
> Can you post a picture of it?
>
> Can you tell me how much it cost?
>
> UE,
> W6ESE - TONY
> NNNN
> ZCZC
>
>
> On 01/15/2014 07:02 AM, Christian Gauger-Cosgrove wrote:
>>
>> On Tuesday, 14 January 2014,  <COURYHOUSE at aol.com
>> <mailto:COURYHOUSE at aol.com>> wrote:
>>  > The Heathkit  PDPD-11!   YES!  We have one on the shelf here ...
>>  >
>>  > This  unit was  called the  H-11  and  was a  DEC- PDP- 11/03 in a
>> heath  case. The  disc drives though were something of  Heathkit's
>> choosing though and  were not RX01s. Op-sys  was  RT-11. We have  the
>> page out of the Heathkit catalog to display with it  but wonder if
>> there  are any other brochures  for it that are colorful or posters
>> that  either can be gotten or  scans of  them gotten to dress this
>> display up a bit.
>>  > (we also have the H-8  and h-89 also!)
>
>
> --
> A good friend will come and bail you out of jail...
> But - a true friend will be sitting next
> to you saying, "Dang... that was fun!"



-- 
Christian M. Gauger-Cosgrove
STCKON08DS0
Contact information available upon request.