4 Dec
2006
4 Dec
'06
3:20 p.m.
OK... so I'm now the new (proud :-) ) owner of a PDP-11/83.
I'm new to the PDP11s, so, I'm not even powering this thing up until I get
educated.
This is the config
In the system (183QA-D2) box:
M8637-EF (2MB ECC RAM)
M8190-AE (11/83 CPU, FPJ11-AA)
X, M9047 (nothing, grant continuity)
M7196 (TSV05 controller)
M7555, M9047 (RQDX3 MFM Winchester/floppy, grant continuity)
M7513, M9404 (RQDXE RQDX extender for RQDX2/3, Q22 extender cpu end)
X (nothing)
X (nothing)
In the BA23-CA expansion:
M9405-YB, M9047 (Q22 extender far end, grant continuity)
M8053-MA (RS232/423 w/DDCMP)
M3104 (8 line ASYNC multiplexer)
M3104 (8 line ASYNC multiplexer)
M77651, M7555 (DRV11-WA 18/22 bit dma general purpose parallel
interface, RQDX3)
M7651, M7546 (DRV11-WA, TKQ50-AA TMSCP for TK50 controller)
X (nothing)
X (nothing)
I recieved this with 1 TK50 drive in the BA23, no hard drives (I have a
decent
selection of MFM drives, but if anyone has any spare Maxtor XT2190 or
XT1140s
let me know). Anyone got any DEC drive sleds ? I could use 4.
Also have a 'port panel' that wen on the rear of the rack these two
boxes were pulled
from... and a large cache of ribbon cables to connect everything up.
Now... for questions:
is FPJ11-AA floating point, and does that mean my cpu card has that
built in ?
What is the max ram ? i.e. how many more M8637-EF (or higher capacity)
cards can be aquired and put in ?
Anyone have a TSV05 tape drive local to Sharon, MA ? Or, anyone in need of
a TSV05 controller ?
What is DDCMP control ROM ? that my M8053-MA has ?
What is a DRV11-WA general purpose 18/22 bit parallel interface ? Can
this be used for a parallel printer ???
As I'd like to have larger storage on it at some point, I'd like to
locate a SCSI
(or possibly ESDI ?) controller. What should I be looking for, anyone have
one ?
I'm looking at running BSD (2.11 ?) and other PDP11 OSes... suggestions ?
There doesn't seem to be a reason to the layout of the grant continuity
cards.
Shouldn't there be one in the left side of the 3rd slot from the top in
the 183QA-D2
(system unit) ?
What is the minimum card config to start testing with ?
Any pointers on how the RQDX3 and RQDXE cards should wire up ? The
RQDXE in the system unit has a wide ribbon cable running to the front
(which I presume breaks into the control/data wiring for an MFM drive
there).. but the RQDX3 doesn't connect to the RQDXE ..
Sorry for the long post... I'm new to PDP11...
Oh.. last thing... does anyone local to Sharon, MA 02067 have a 'proper'
DEC RAC enclosure the is 'correct'/'period' for a PDP-11/83 ? (not
full size please... this 11/83 is in my 2nd floor computer room... I
currently
do not want a full height 19" rack in there... something deskside size plz).
Thnk that covers it for now.
Thanks in adance everyone,
-- Curt
5 Dec
5 Dec
7:06 a.m.
On Mon, 2006-12-04 at 15:20 -0500, Curtis H. Wilbar Jr. wrote:
OK... so I'm now the new (proud :-) ) owner of a
PDP-11/83.
Congratulations!!
I recieved this with 1 TK50 drive in the BA23, no hard
drives (I have a
decent
selection of MFM drives, but if anyone has any spare Maxtor XT2190 or
XT1140s
let me know). Anyone got any DEC drive sleds ? I could use 4.
In my BA123 the disks have been screwed into the sled slot, I don't know
if this is doable with the BA23.
is FPJ11-AA floating point, and does that mean my cpu
card has that
built in ?
Yes, the PDP-11/83 CPU has built-in floating-point.
What is the max ram ? i.e. how many more M8637-EF (or
higher capacity)
cards can be aquired and put in ?
The maximum amount of RAM you can put in a PDP-11 is 4 MB. 2MB should be
plenty for everything but 2.11BSD - in which case it is merely
sufficient. You also seem to have PMI memory, which means that memory
accesses go via the private memory interconnect rather than the main I/O
bus. Many PDP-11/83s (like mine :\) came with QBUS memory.
Anyone have a TSV05 tape drive local to Sharon, MA ?
Or, anyone in need of
a TSV05 controller ?
The TSV05 is, I believe, a Pertec controller (which shipped with a
Cipher M890/M891 or something thereabouts badged as a TSV05). It should
work with any Pertec tape drive.
What is DDCMP control ROM ? that my M8053-MA has ?
Something related to DECnet over serial ports, that's all I know about
that, though I could guess that it's used for network booting.
What is a DRV11-WA general purpose 18/22 bit parallel
interface ? Can
this be used for a parallel printer ???
It is general purpose.. :) I think this is just 64 bidirectional I/O
ports which can be used for most things, I have two or three myself, but
I haven't toyed with them. Never tried putting a Centronics cable on it.
As I'd like to have larger storage on it at some
point, I'd like to
locate a SCSI
(or possibly ESDI ?) controller. What should I be looking for, anyone have
one ?
The SCSI controllers are relatively hard to come by, but the Emulex DQ07
(iirc) seems to be one of the most common, and is the one I have.
I'm looking at running BSD (2.11 ?) and other
PDP11 OSes... suggestions ?
2.11 will run happily on your machine, if you give it disk space
enough.
There doesn't seem to be a reason to the layout of
the grant continuity
cards.
Shouldn't there be one in the left side of the 3rd slot from the top in
the 183QA-D2
(system unit) ?
What is the minimum card config to start testing with ?
CPU. The CPU has a built-in serial port and will give out a diagnostic
if it cannot find RAM.
Any pointers on how the RQDX3 and RQDXE cards should
wire up ? The
RQDXE in the system unit has a wide ribbon cable running to the front
(which I presume breaks into the control/data wiring for an MFM drive
there).. but the RQDX3 doesn't connect to the RQDXE ..
IIRC, my RQDXE does connect with the wide ribbon cable to the RQDX3. The
connectors for the MFM and FD are on the RQDXE itself.
Sorry for the long post... I'm new to PDP11...
No problem, hope you'll have fun with it. :)
-Tore
7:27 a.m.
On 12/6/06, Tore Sinding Bekkedal <toresbe at ifi.uio.no> wrote:
I don't know either... I've only ever used sleds with a BA23.
I haven't tried it myself, but it may be possible to fabricate
something close enough to work with ordinary shop tools and a sheet of
plexiglass/perspex. Has anyone on the list ever tried to make DEC
drive sleds from scratch?
I would think it's to boot the machine over DDCMP from a MOP server,
but I don't have any direct experience with it.
It's just unformatted parallel I/O with, ISTR, handshaking lines. You
might be able to hook a parallel printer to one, but there's a good
chance you'd need to invert one or more of the handshake lines, and
you'd probably have to write your own driver to emulate an LPV11, but
with DRV11-W I/O instructions.
They were commonly used for a wide channel CPU-to-CPU interface, or to
attach strange peripherals that had no Qbus interfaces. I don't
recall ever seeing them used as printer ports (the PIO-driven LPV11
being much cheaper at the time).
Viking and CMD controllers were also common, IIRC.
Unless you have a small quantity of ESDI drives, I'd suggest you be on
the lookout for a Qbus SCSI controller. They aren't usually under
$250 US, but even at that price (if it hasn't gone up recently), the
ability to use more modern drives is rather nice unless you are more
interested in a 100% vintage arrangement from before the time of SCSI
(by the time the 11/83 came around, SCSI drives weren't that rare on
DEC machines, but the controllers never were inexpensive).
2BSD is a nice choice if you want Unix. RT-11 was common for smaller
systems, and RSX-11/M and RSTS were common for larger configurations.
If you aren't married to Unix, RT-11 is simple enough to pick up
quickly, especially if you have much MS-DOS or CP/M experience. I
went the other way - RT-11 first, then CP/M... made learning to get
around on a Kaypro a snap.
There are lesser-known PDP-11 OSes, but between Unix and RT-11, you
should have plenty to play around with.
-ethan
On Mon, 2006-12-04 at 15:20 -0500, Curtis H. Wilbar
Jr. wrote:
Indeed - nicely loaded machine.
OK... so I'm now the new (proud :-) ) owner
of a PDP-11/83.
Congratulations!! Anyone got
any DEC drive sleds ? I could use 4.
In my BA123 the disks have been screwed into the sled slot, I don't know
if this is doable with the BA23. What is DDCMP
control ROM ? that my M8053-MA has ?
Something related to DECnet over serial ports, that's all I know about
that, though I could guess that it's used for network booting. What is a
DRV11-WA general purpose 18/22 bit parallel interface ? Can
this be used for a parallel printer ???
It is general purpose.. :) I think this is just 64 bidirectional I/O
ports which can be used for most things, I have two or three myself, but
I haven't toyed with them. Never tried putting a Centronics cable on it. As I'd
like to have larger storage on it at some point, I'd like to
locate a SCSI
(or possibly ESDI ?) controller. What should I be looking for, anyone have
one ?
The SCSI controllers are relatively hard to come by, but the Emulex DQ07
(iirc) seems to be one of the most common, and is the one I have. I'm
looking at running BSD (2.11 ?) and other PDP11 OSes... suggestions ?
2.11 will run happily on your machine, if you give it disk space enough. 
10:16 a.m.
On 12/5/06, Ethan Dicks <ethan.dicks at
gmail.com> wrote:
Unless you have a small quantity of ESDI drives, I'd suggest you be on
the lookout for a Qbus SCSI controller. They aren't usually under
$250 US, but even at that price (if it hasn't gone up recently), the
ability to use more modern drives is rather nice unless you are more
interested in a 100% vintage arrangement from before the time of SCSI
(by the time the 11/83 came around, SCSI drives weren't that rare on
DEC machines, but the controllers never were inexpensive).
Or you can take a look of my project (http://www.mscpscsi.com). After fixing
several bugs I am more confident than ever that this project will be
successful. Now I am even trying to get a PDP11 to further test the MSCP
commands of "erase" and "format" (never used by NetBSD) but the PDP11
is
very heavy to haul and I need to find a spare time to deal with this issue.
Having 3 commitments with 3 professors, I can barely find any time.
vax, 9000
11:43 a.m.
So how big was the spike after you posted the web address?
On Tue, 5 Dec 2006, 9000 VAX wrote:
Or you can take a look of my project
(http://www.mscpscsi.com).
vax, 9000
9:01 p.m.
On 12/5/06, cctech at porky.vax-11.org <cctech at porky.vax-11.org> wrote:
So how big was the spike after you posted the web address?
I don't know. It is kindly hosted by Brian H (on the list too).
vax, 9000
On Tue, 5 Dec 2006, 9000 VAX wrote:
Or you can take a look of my project
(http://www.mscpscsi.com).
vax, 9000
11:45 a.m.
At 1:27 AM +1300 12/6/06, Ethan Dicks wrote:
It has been my experience that the Viking controllers were *very*
common and rebadged by at least a couple companies. All of my main
PDP-11's are using Viking QDT & UDT controllers.
I don't know either... I've only ever used
sleds with a BA23.
I haven't tried it myself, but it may be possible to fabricate
something close enough to work with ordinary shop tools and a sheet of
plexiglass/perspex. Has anyone on the list ever tried to make DEC
drive sleds from scratch?
I might be getting it confused with a 3rd party chassis, but I'm
pretty sure I've seen a metal drive sled, rather than the standard
DEC Plastic sleds. At the same time, getting the thickness right is
what will cause problems I suspect.
The SCSI
controllers are relatively hard to come by, but the Emulex DQ07
(iirc) seems to be one of the most common, and is the one I have.
Viking and CMD controllers were also common, IIRC. Unless you have a small quantity of ESDI drives,
I'd suggest you be on
the lookout for a Qbus SCSI controller. They aren't usually under
$250 US, but even at that price (if it hasn't gone up recently), the
ability to use more modern drives is rather nice unless you are more
interested in a 100% vintage arrangement from before the time of SCSI
(by the time the 11/83 came around, SCSI drives weren't that rare on
DEC machines, but the controllers never were inexpensive).
If he looks for a ESDI controller, I'd recommend the Webster WQESD/04
controller. Personally it is the one non-SCSI 3rd party controller
I'd want to run (I did for several years).
2BSD is a nice choice if you want Unix. RT-11 was
common for smaller
systems, and RSX-11/M and RSTS were common for larger configurations.
If you aren't married to Unix, RT-11 is simple enough to pick up
quickly, especially if you have much MS-DOS or CP/M experience. I
went the other way - RT-11 first, then CP/M... made learning to get
around on a Kaypro a snap.
I've found one of the advantages of SCSI is that it's easy to use
drive trays to run multiple OS's. RT-11 is very nice. Somehow
either RSX-11M or RSX-11M+ seem a bit more appropriate for the system
in question. I'm not sure I'd recommend RSTS/E as a first OS.
BTW, another advantage of SCSI is attaching a CD-ROM drive, which can
make installing an OS easier.
Zane
--
| Zane H. Healy | UNIX Systems Administrator |
| healyzh at aracnet.com (primary) | OpenVMS Enthusiast |
| MONK::HEALYZH (DECnet) | Classic Computer Collector |
+----------------------------------+----------------------------+
| Empire of the Petal Throne and Traveller Role Playing, |
| PDP-10 Emulation and Zane's Computer Museum. |
| http://www.aracnet.com/~healyzh/ |
10:18 p.m.
On Tuesday 05 December 2006 11:45, Zane H. Healy wrote:
At 1:27 AM +1300 12/6/06, Ethan Dicks wrote:
So, do you have any info on making them work? I've got a pair of them,
which I got out of 3rd party (embedded) 11/23 systems, but I haven't had
any luck getting them to talk to drives. The system can talk to the
controller (I stuck it into a QBUS VAX and could do a "show uqssp" to
it), but it didn't seem to see any drives, and the activity lights on
the drives didn't ever blink (though the LED on the card did blink when
it should have been talking to the SCSI bus).
Pat
--
Purdue University ITAP/RCAC --- http://www.rcac.purdue.edu/
The Computer Refuge --- http://computer-refuge.org
Viking and CMD controllers were also common, IIRC.
It has been my experience that the Viking controllers were *very*
common and rebadged by at least a couple companies. All of my main
PDP-11's are using Viking QDT & UDT controllers.
11:52 p.m.
At 10:18 PM -0500 12/5/06, Patrick Finnegan wrote:
On Tuesday 05 December 2006 11:45, Zane H. Healy
wrote:
Take a look on ftp://ftp.avanthar.com/dan/viking_scsi and you will
find the documentation. Warning, it really helps to have a bulkhead
panel that allows you to plug in a serial terminal.
The boards can be configured as Disk, Tape, Disk & Tape, or Disk &
PDP-11 boot depending on the PAL's installed. You need fairly new
firmware for them to work with a CD-ROM drive. They're pretty picky
about what CD-ROM drives they'll work with, but I've had good luck
with Plextor Caddy drives.
Zane
--
| Zane H. Healy | UNIX Systems Administrator |
| healyzh at aracnet.com (primary) | OpenVMS Enthusiast |
| MONK::HEALYZH (DECnet) | Classic Computer Collector |
+----------------------------------+----------------------------+
| Empire of the Petal Throne and Traveller Role Playing, |
| PDP-10 Emulation and Zane's Computer Museum. |
| http://www.aracnet.com/~healyzh/ |
At 1:27 AM +1300 12/6/06, Ethan Dicks wrote:
So, do you have any info on making them work? I've got a pair of them,
which I got out of 3rd party (embedded) 11/23 systems, but I haven't had
any luck getting them to talk to drives. The system can talk to the
controller (I stuck it into a QBUS VAX and could do a "show uqssp" to
it), but it didn't seem to see any drives, and the activity lights on
the drives didn't ever blink (though the LED on the card did blink when
it should have been talking to the SCSI bus). Viking and CMD controllers were also common, IIRC.
It has been my experience that the Viking controllers were *very*
common and rebadged by at least a couple companies. All of my main
PDP-11's are using Viking QDT & UDT controllers. 
11:56 p.m.
Patrick Finnegan wrote:
On Tuesday 05 December 2006 11:45, Zane H. Healy
wrote:
They're probably toast. You should ship them to me for diagnostics
and proper disposal.
Doc
At 1:27 AM +1300 12/6/06, Ethan Dicks wrote:
So, do you have any info on making them work? I've got a pair of them,
which I got out of 3rd party (embedded) 11/23 systems, but I haven't had
any luck getting them to talk to drives. The system can talk to the
controller (I stuck it into a QBUS VAX and could do a "show uqssp" to
it), but it didn't seem to see any drives, and the activity lights on
the drives didn't ever blink (though the LED on the card did blink when
it should have been talking to the SCSI bus). Viking and CMD controllers were also common, IIRC.
It has been my experience that the Viking controllers were *very*
common and rebadged by at least a couple companies. All of my main
PDP-11's are using Viking QDT & UDT controllers. 
3:08 p.m.
On Mon, 2006-12-04 at 15:20 -0500, Curtis H. Wilbar
Jr. wrote:
> OK... so I'm now the new (proud :-) ) owner of a PDP-11/83.
Congrats! I've been battling with a reluctant 11/73 today in the workshop,
on work's time :) We have some RD53s to test for a customer.....
> There doesn't seem to be a reason to the
layout of the grant continuity
> cards.
> Shouldn't there be one in the left side of the 3rd slot from the top in
> the 183QA-D2
> (system unit) ?
No, the first 3 slots of the Q22 bus carry the grant continuity on the CD
portion so a dual-height card in the AB side of slot 3 is fine.
> Any pointers on how the RQDX3 and RQDXE cards
should wire up ? The
> RQDXE in the system unit has a wide ribbon cable running to the front
> (which I presume breaks into the control/data wiring for an MFM drive
> there).. but the RQDX3 doesn't connect to the RQDXE ..
I've just done this today - the RQDXE goes in the last AB slot with the BA23
drive bay cable going to the back-most connector, the external port
(multi-coloured cable) goes in the middle connector and the cable to the
RQDX3 goes to the front-most connector, ie nearest the backplane fingers.
There are jumpers to select too, and the manual for those is available on
MANX and Bitsavers.....many thanks to the folks involved there.
--
Adrian/Witchy
Binary Dinosaurs creator/curator
Www.binarydinosaurs.co.uk - the UK's biggest private home computer
collection?
8:45 p.m.
At 8:08 PM +0000 12/5/06, Adrian Graham wrote:
We have some RD53s to test for a customer.....
You have my sympathy.
Zane
--
| Zane H. Healy | UNIX Systems Administrator |
| healyzh at aracnet.com (primary) | OpenVMS Enthusiast |
| MONK::HEALYZH (DECnet) | Classic Computer Collector |
+----------------------------------+----------------------------+
| Empire of the Petal Throne and Traveller Role Playing, |
| PDP-10 Emulation and Zane's Computer Museum. |
| http://www.aracnet.com/~healyzh/ |
6 Dec
6 Dec
2 p.m.
On 6/12/06 01:45, "Zane H. Healy" <healyzh at aracnet.com> wrote:
At 8:08 PM +0000 12/5/06, Adrian Graham wrote:
Indeed, it looks like the original boot drive (also an RD53) long gave up
the ghost, which is a shame because it had RT11 5.4 and one of the systems I
wrote in the 1980's......
--
Adrian/Witchy
Binary Dinosaurs creator/curator
Www.binarydinosaurs.co.uk - the UK's biggest private home computer
collection?
We have some RD53s to test for a customer.....
You have my sympathy. 
5:27 p.m.
Adrian Graham wrote:
On 6/12/06 01:45, "Zane H. Healy"
<healyzh at aracnet.com> wrote:
What actually fails in them?
Gordon.
At 8:08 PM +0000 12/5/06, Adrian Graham wrote:
Indeed, it looks like the original boot drive (also an RD53) long gave up
the ghost, which is a shame because it had RT11 5.4 and one of the systems I
wrote in the 1980's...... We have some RD53s to test for a customer.....
You have my sympathy.
7 Dec
7 Dec
2:20 p.m.
On 6/12/06 22:27, "Gordon JC Pearce" <gordon at gjcp.net> wrote:
Head actuator I think; it powers up and spins up, doesn't sound headcrashed
but I can't hear or feel the heads move.....
--
Adrian/Witchy
Binary Dinosaurs creator/curator
Www.binarydinosaurs.co.uk - the UK's biggest private home computer
collection?
Indeed, it
looks like the original boot drive (also an RD53) long gave up
the ghost, which is a shame because it had RT11 5.4 and one of the systems I
wrote in the 1980's......
What actually fails in them?
3:07 p.m.
Adrian Graham wrote:
On 6/12/06 22:27, "Gordon JC Pearce"
<gordon at gjcp.net> wrote:
Head actuator I think; it powers up and spins up, doesn't sound headcrashed
but I can't hear or feel the heads move.....
I know that some old MFM drives *did* end up with the heads "stuck" in
place. A few people have said that RD53s are bad for that, so it might
be worth a shot. You can't make it work any less...
Gordon.
Indeed,
it looks like the original boot drive (also an RD53) long gave up
the ghost, which is a shame because it had RT11 5.4 and one of the systems I
wrote in the 1980's......
What actually fails in them? 
9:10 p.m.
On Thu, Dec 07, 2006 at 07:20:05PM +0000, Adrian Graham wrote:
On 6/12/06 22:27, "Gordon JC Pearce"
<gordon at gjcp.net> wrote:
Head actuator I think; it powers up and spins up, doesn't sound headcrashed
but I can't hear or feel the heads move.....
Definitely check for stiction, it's a very common problem on RD53s. If
the data on them is worth saving, you can probably make a clean enough
environment in your home or office to open up the drive assembly and
nudge the head loose from the sticky rubber that it's parked against.
You can probably get at least one good read out of it without it
crashing (I know folks who've opened up their RD53s, reassembled them,
and run them successfully for months afterward. YMMV!)
-Seth
Indeed,
it looks like the original boot drive (also an RD53) long gave up
the ghost, which is a shame because it had RT11 5.4 and one of the systems I
wrote in the 1980's......
What actually fails in them? 
11:57 p.m.
Seth J. Morabito wrote:
On Thu, Dec 07, 2006 at 07:20:05PM +0000, Adrian
Graham wrote:
Stiction, as I've eperienced it (Quantum 100Meg drives as used in Suns),
keeps the
drive motor from spinning up the disk (because the heads are stuck to
the disk).
His drive spins up... he just doesn't hear the heads move... which
would lead me to
believe:
1. The problem I've seen with the rubber bumper out of adjustment
2. rubber bumper has gone sticky... and the heads can't move off of it
(in which case
it could be cured like head/platter stiction)
3. failure of PCB to operate head actuator voice coil... this would
require a replacement
drive PCB.
-- Curt
On 6/12/06 22:27, "Gordon JC Pearce"
<gordon at gjcp.net> wrote:
Head actuator I think; it powers up and spins up, doesn't sound
headcrashed
but I can't hear or feel the heads move.....
Definitely check for stiction, it's a very common problem on RD53s. If
the data on them is worth saving, you can probably make a clean enough
environment in your home or office to open up the drive assembly and
nudge the head loose from the sticky rubber that it's parked against.
You can probably get at least one good read out of it without it
crashing (I know folks who've opened up their RD53s, reassembled them,
and run them successfully for months afterward. YMMV!)
Indeed,
it looks like the original boot drive (also an RD53) long gave up
the ghost, which is a shame because it had RT11 5.4 and one of the systems I
wrote in the 1980's......
What actually fails in them?
-Seth
8 Dec
8 Dec
midnight
Seth J. Morabito wrote:
On Thu, Dec 07, 2006 at 07:20:05PM +0000, Adrian
Graham wrote:
gah... I should have read beyond 'check for stiction'... the sticktion
you describe
is what I laid out in option 2... oops... its late... shouldn't be
reading e-mail...
so I didn't read beyond the the first line before commenting... doh !
The one drive I fixed it wasn't sticking to it (physically)... but the
drive was
holding the heads against it hard electrically (felt stuck with drive
on). I
think it holds hard against this looking for track 0... then fine ajusts
for track 0
center.... if that bumper changes geometry with age, or gets moved over
time...
then it can't get a read on track 0.... hence why adjusting it by a
thousandth if
an inch in my case got the drive working nicely....
-- Curt
-- Curt
On 6/12/06 22:27, "Gordon JC Pearce"
<gordon at gjcp.net> wrote:
Head actuator I think; it powers up and spins up, doesn't sound
headcrashed
but I can't hear or feel the heads move.....
Definitely check for stiction, it's a very common problem on RD53s. If
the data on them is worth saving, you can probably make a clean enough
environment in your home or office to open up the drive assembly and
nudge the head loose from the sticky rubber that it's parked against.
You can probably get at least one good read out of it without it
crashing (I know folks who've opened up their RD53s, reassembled them,
and run them successfully for months afterward. YMMV!)
Indeed,
it looks like the original boot drive (also an RD53) long gave up
the ghost, which is a shame because it had RT11 5.4 and one of the systems I
wrote in the 1980's......
What actually fails in them?
-Seth
7 Dec
7 Dec
11:24 p.m.
Adrian Graham wrote:
On 6/12/06 22:27, "Gordon JC Pearce"
<gordon at gjcp.net> wrote:
Head actuator I think; it powers up and spins up, doesn't sound headcrashed
but I can't hear or feel the heads move.....
I personally had one fail (1325) that had to do with locating track 0
(which appears to
be initially probed for by a full stroke into a rubber bumper). I think
the rubber changes
or becomes out of adjustment with age... in my case I opened the HDA
(felt I had nothing
to lose at that point), and tweaked the position by around 1 thousandth
of an inch...
the drive then came ready every time and worked fine.
I've also heard of the spindle motor brake dragging not allowing the
drive to get up to
full speed rotation... and that can be adjusted w/o opening the HDA...
it is on the
bottom under the circuit board.
-- Curt
Indeed,
it looks like the original boot drive (also an RD53) long gave up
the ghost, which is a shame because it had RT11 5.4 and one of the systems I
wrote in the 1980's......
What actually fails in them?
6 Dec
6 Dec
11:06 p.m.
At 7:00 PM +0000 12/6/06, Adrian Graham wrote:
Indeed, it looks like the original boot drive (also an
RD53) long gave up
the ghost, which is a shame because it had RT11 5.4 and one of the systems I
wrote in the 1980's......
If it's just something like the heads sticking, it might be possible
to revive the drive, at least long enough to get the data off. BTW,
while several other people have done this over the years, I didn't
have any luck the one time I tried to revive an RD53, so you'll want
to ask someone other than me any questions. :^)
I've even heard of people running the drives for years after fixing
the problem.
Zane
--
| Zane H. Healy | UNIX Systems Administrator |
| healyzh at aracnet.com (primary) | OpenVMS Enthusiast |
| MONK::HEALYZH (DECnet) | Classic Computer Collector |
+----------------------------------+----------------------------+
| Empire of the Petal Throne and Traveller Role Playing, |
| PDP-10 Emulation and Zane's Computer Museum. |
| http://www.aracnet.com/~healyzh/ |
6410
days inactive
6414
days old
20 comments
12 participants
participants (12)
-
cctech＠porky.vax-11.org -
curtis＠hawkmountain.net -
doc＠mdrconsult.com -
ethan.dicks＠gmail.com -
gordon＠gjcp.net -
healyzh＠aracnet.com -
pat＠computer-refuge.org -
rescue＠hawkmountain.net -
sethm＠loomcom.com -
toresbe＠ifi.uio.no -
vax9000＠gmail.com -
witchy＠binarydinosaurs.co.uk