29 Oct
2015
29 Oct
'15
9:38 a.m.
From: Ben Sinclair
A while back I was talking to someone else who
suggested using a ribbon
cable from the controller to directly inside the drive.
I've heard that suggestion too...
That technically will fit if I remove the ribbon
inside the drive that
goes to the external connectors, but then I won't have a terminator
installed. I do have a terminator though!
The cable from the CPU would have to have two connectors on the RL02 end;
one would plug into the drive's logic board, and the other to the outbound
connector, where you can plug in the terminator.
AFAIK that cable is purely a bus (i.e. no radial per-drive wires), so you
should just be able to run it to the second connector, no issue. However,
I'm too lazy to check to make sure that's absolutely 100% accurate. :-)
I think what I really need, since I don't have a
cab kit or anything,
is a bc80m, which I believe is a ribbon with a ground lug on the
controller side, and whatever type of connector the drive uses on the
other end.
I think you mean a Berg connector which will plug directly into the RLV11,
not "ground lug", right? Yes, if you don't have a cab kit, that's the
cable
you need. It's not a ribbon cable, but a round cable (the connectors the
drives use only come in regular cable form, not ribbon cable - AFAIK).
Not that I can even find a cable like that anywhere
currently...
RLOx cables of _any_ kind are very hard to find. There are discussions under
way about making new ones; there is a supply (used) of the wierd-ass
connector that plugs into the back of the drive which could be used.
I unfortunately don't have an extender card...
Others have pointed you at Douglas; here's the page for all their
extender cards:
http://www.douglas.com/index.php/off-the-shelf-solutions/bread-boards-by-fu…
which includes a hex, but those aren't any use (that I can think of) to
people with QBUS machines.
(Useful things to have it you're trying to maintain a vintage PDP-11; one is,
perforce, forced to become one's own Field Circus person - unless you're lucky
and happen to live close to a PDP-11 hardware expert who's willing to come
salve one's machine.)
From: Johnny Billquist
Well, not important. We're now beyond that point.
The boards are
working well enough that we can address them...
Well, but he might still have a problem on them. Although fixing such would
be a challenge...
Noel
29 Oct
29 Oct
9:52 a.m.
Thanks! I did find someone who has the bc80m cable available, which I
believe is a ribbon type of connector with a ground strap on one end,
then a round cable to the berg connector for the back of the RL02. I
think it's the cable pictured here:
http://www.cosam.org/computers/dec/pdp11-23/20080403.html
Does that sound right?
The RLV11 and RLV12 seem hard to find, at least on eBay, so fixing
this one might be the way to go! Of course, I'll snag an extra if I
see one for a decent price.
Feel free to move to Iowa and help me with my PDP, Noel!
On Thu, Oct 29, 2015 at 11:38 AM, Noel Chiappa <jnc at mercury.lcs.mit.edu> wrote:
--
Ben Sinclair
ben at bensinclair.com
From: Ben
Sinclair
A while back I was talking to someone else who
suggested using a ribbon
cable from the controller to directly inside the drive.
I've heard that suggestion too...
That technically will fit if I remove the ribbon
inside the drive that
goes to the external connectors, but then I won't have a terminator
installed. I do have a terminator though!
The cable from the CPU would have to have two connectors on the RL02 end;
one would plug into the drive's logic board, and the other to the outbound
connector, where you can plug in the terminator.
AFAIK that cable is purely a bus (i.e. no radial per-drive wires), so you
should just be able to run it to the second connector, no issue. However,
I'm too lazy to check to make sure that's absolutely 100% accurate. :-)
I think what I really need, since I don't
have a cab kit or anything,
is a bc80m, which I believe is a ribbon with a ground lug on the
controller side, and whatever type of connector the drive uses on the
other end.
I think you mean a Berg connector which will plug directly into the RLV11,
not "ground lug", right? Yes, if you don't have a cab kit, that's the
cable
you need. It's not a ribbon cable, but a round cable (the connectors the
drives use only come in regular cable form, not ribbon cable - AFAIK).
Not that I can even find a cable like that
anywhere currently...
RLOx cables of _any_ kind are very hard to find. There are discussions under
way about making new ones; there is a supply (used) of the wierd-ass
connector that plugs into the back of the drive which could be used.
I unfortunately don't have an extender
card...
Others have pointed you at Douglas; here's the page for all their
extender cards:
http://www.douglas.com/index.php/off-the-shelf-solutions/bread-boards-by-fu…
which includes a hex, but those aren't any use (that I can think of) to
people with QBUS machines.
(Useful things to have it you're trying to maintain a vintage PDP-11; one is,
perforce, forced to become one's own Field Circus person - unless you're lucky
and happen to live close to a PDP-11 hardware expert who's willing to come
salve one's machine.)
From: Johnny Billquist
Well, not important. We're now beyond that
point. The boards are
working well enough that we can address them...
Well, but he might still have a problem on them. Although fixing such would
be a challenge...
Noel 
10:17 a.m.
On Thu, Oct 29, 2015 at 12:52 PM, Ben Sinclair <ben at bensinclair.com> wrote:
Thanks! I did find someone who has the bc80m cable
available, which I
believe is a ribbon type of connector with a ground strap on one end,
then a round cable to the berg connector for the back of the RL02. I
think it's the cable pictured here:
http://www.cosam.org/computers/dec/pdp11-23/20080403.html
Yes. That's a BC80M, but it's not a ribbon cable on the controller
end, it's the splayed end of the round cable (12 pair + 1, IIRC) with
crimped gold pins and a 44 position Berg connector. You can use those
if you don't have a cab kit (which is really just a bracket for the
rack, a 40-pin ribbon cable, and one of those odd ZIF connectors like
on the back of the drive to transition from flat cable to round cable)
but then you'll need a drive-to-drive RL cable.
The RLV11 and RLV12 seem hard to find, at least on
eBay
It's been a long time since these were easy to find.
-ethan
10:37 a.m.
I only have one RL02, so I think that cable should work. I ordered it anyway!
I'll keep an eye out for other controllers, but I think I will order
an extender and attempt to debug the one I have.
On Thu, Oct 29, 2015 at 12:17 PM, Ethan Dicks <ethan.dicks at gmail.com> wrote:
On Thu, Oct 29, 2015 at 12:52 PM, Ben Sinclair <ben
at bensinclair.com> wrote:
--
Ben Sinclair
ben at bensinclair.com
Thanks! I did find someone who has the bc80m
cable available, which I
believe is a ribbon type of connector with a ground strap on one end,
then a round cable to the berg connector for the back of the RL02. I
think it's the cable pictured here:
http://www.cosam.org/computers/dec/pdp11-23/20080403.html
Yes. That's a BC80M, but it's not a ribbon cable on the controller
end, it's the splayed end of the round cable (12 pair + 1, IIRC) with
crimped gold pins and a 44 position Berg connector. You can use those
if you don't have a cab kit (which is really just a bracket for the
rack, a 40-pin ribbon cable, and one of those odd ZIF connectors like
on the back of the drive to transition from flat cable to round cable)
but then you'll need a drive-to-drive RL cable.
The RLV11 and RLV12 seem hard to find, at least
on eBay
It's been a long time since these were easy to find.
-ethan
10:45 a.m.
On Thu, Oct 29, 2015 at 1:37 PM, Ben Sinclair <ben at bensinclair.com> wrote:
I only have one RL02, so I think that cable should
work. I ordered it anyway!
That cable (BC80M) will work even if you get a second drive. No
matter how the first drive is attached to the controller, to add a
drive, you remove the terminator from the first drive, add a
drive-to-drive cable between the two drives, then move the terminator
to the second drive.
Can anyone with experience from back in the day comment on why there
is a BC80M? Why all the controllers didn't just use the flat cable to
a cab kit and a drive-to-drive cable? Cost? Length? EMI reduction
from running the BC80M into a BA23, etc, and only
pushing shielded
cable outside the CPU enclosure? Is the flat-cable-and-cab-kit
pre-FCC only?
I'll keep an eye out for other controllers, but I
think I will order
an extender and attempt to debug the one I have.
It seems to be mostly working, so with luck, it's a single IC, once
you narrow it down.
-ethan
11:26 a.m.
On 2015-10-29 18:45, Ethan Dicks wrote:
On Thu, Oct 29, 2015 at 1:37 PM, Ben Sinclair <ben
at bensinclair.com> wrote:
When you had machines with an RL-drive "internal", you normally did not
use a cab kit. That was for external drives. The same is true for all
other DEC drives I know as well. I've certainly seen direct cabling
internally for SDI drives as well as external cabling for RX50 and TK50.
But the only machine I know have an "internal" RL drive is the VAX-86x0,
but maybe there were others as well...
And no, the VAX do not have a cab kit for the RL drive. Direct cable
I only have one RL02, so I think that cable
should work. I ordered it anyway!
That cable (BC80M) will work even if you get a second drive. No
matter how the first drive is attached to the controller, to add a
drive, you remove the terminator from the first drive, add a
drive-to-drive cable between the two drives, then move the terminator
to the second drive.
Can anyone with experience from back in the day comment on why there
is a BC80M? Why all the controllers didn't just use the flat cable to
a cab kit and a drive-to-drive cable? Cost? Length? EMI reduction
from running the BC80M into a BA23, etc, and only pushing shielded
cable outside the CPU enclosure? Is the flat-cable-and-cab-kit
pre-FCC only? from the RLV21 to the RL02.
Johnny
--
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: bqt at softjar.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
11:52 a.m.
In case anyone happens to be looking for the cab kit, conflansrd / JT
Computer has had one listed on eBay for a while:
http://www.ebay.com/itm/151628333033
CK-RLV1A-KA 15' CABLE RLV12 M8061 CABKIT FOR BA23 (USED)
Asking $50, but they have been known to accept lower offers.
12:22 p.m.
On Thu, Oct 29, 2015 at 2:52 PM, Glen Slick <glen.slick at gmail.com> wrote:
In case anyone happens to be looking for the cab kit,
conflansrd / JT
Computer has had one listed on eBay for a while:
http://www.ebay.com/itm/151628333033
CK-RLV1A-KA 15' CABLE RLV12 M8061 CABKIT FOR BA23 (USED)
That's not the cab kit I was thinking of, but it's _a_ cab kit.
The one I'm thinking of (and can't find a picture online of) is a
black-painted metal bracket with space to mount two of those ZIF
connectors, with a bit of bent metal that positions a threaded hole
about the same relationship to the drive cable as the strain-relief
screw point on the back of the drives. It's really just a metal box
with 4 sides, a hole for the ZIF connectors, and open to the side with
the round cables, with a lip for that screw. You mount this metal box
somewhere on your H960 (or other rack) and run a BC08 cable into your
RL11. I know I have one on my 11/24, and I probably have 2-3 more for
other systems.
-ethan
1:37 p.m.
On 2015-10-29 20:22, Ethan Dicks wrote:
On Thu, Oct 29, 2015 at 2:52 PM, Glen Slick
<glen.slick at gmail.com> wrote:
Sounds like the typical cab kit for large cabinets. Not something you
normally want if you have a BA23... :-)
Ie. there are several can kits, for different cabs.
Johnny
--
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: bqt at softjar.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
In case anyone happens to be looking for the cab
kit, conflansrd / JT
Computer has had one listed on eBay for a while:
http://www.ebay.com/itm/151628333033
CK-RLV1A-KA 15' CABLE RLV12 M8061 CABKIT FOR BA23 (USED)
That's not the cab kit I was thinking of, but it's _a_ cab kit.
The one I'm thinking of (and can't find a picture online of) is a
black-painted metal bracket with space to mount two of those ZIF
connectors, with a bit of bent metal that positions a threaded hole
about the same relationship to the drive cable as the strain-relief
screw point on the back of the drives. It's really just a metal box
with 4 sides, a hole for the ZIF connectors, and open to the side with
the round cables, with a lip for that screw. You mount this metal box
somewhere on your H960 (or other rack) and run a BC08 cable into your
RL11. I know I have one on my 11/24, and I probably have 2-3 more for
other systems. 
12:35 p.m.
When you had machines with an RL-drive "internal", you normally did not
use a cab kit. That was for external drives. The same is true for all
other DEC drives I know as well. I've certainly seen direct cabling
internally for SDI drives as well as external cabling for RX50 and TK50.
The RL01 version of the MINC doesn;t use the cab kit. It uses that Berg-RL
cable from the RLV11 in the MINC chassis to the first RL01, then the normal
RL-RL cable between the drives. I am not sure if that's an 'internal drive',
the
2 RL01s are fitted into a small rack cabinet, the MINC chassis fits on top held
down by 2 captive screws, it doesn't mount on slide rails or anything like that.
Conversely the VAX11/730 has an RL02 controller as part of the IDC (Integrated
Disk Controller, it talks directly to internal CPU buses rather than sitting on the
Unibus). Here, there is a Berg-Berg cable from the IDC to a connector on the
CPU distribution panel (which also carries the console terminal connector, etc) and
then RL-RL cables from that to the first RL02 and between RL02s. Again, I don't
know if you call that an internal drive, the CPU is a separate rackmouting box,
the drive is another rackmounitng unit, but it was common to have 'packaged'
configurations of this machine, some of which included RL02s.
-tony
1:41 p.m.
On 2015-10-29 20:35, tony duell wrote:
I used "internal" in a somewhat loose sense. I think of it as internal
if it was intended to be in the same cabinet. Thus, a short distance
between the CPU and the drive, and the cabling do not go outside that
cabinet.
Now, you could have a cab kit even under those circumstances. I think
mostly of "internal" as when the whole package was delivered that way
When you had machines with an RL-drive "internal", you normally did not
use a cab kit. That was for external drives. The same is true for all
other DEC drives I know as well. I've certainly seen direct cabling
internally for SDI drives as well as external cabling for RX50 and TK50.
The RL01 version of the MINC doesn;t use the cab kit. It uses that Berg-RL
cable from the RLV11 in the MINC chassis to the first RL01, then the normal
RL-RL cable between the drives. I am not sure if that's an 'internal drive',
the
2 RL01s are fitted into a small rack cabinet, the MINC chassis fits on top held
down by 2 captive screws, it doesn't mount on slide rails or anything like that.
Conversely the VAX11/730 has an RL02 controller as part of the IDC (Integrated
Disk Controller, it talks directly to internal CPU buses rather than sitting on the
Unibus). Here, there is a Berg-Berg cable from the IDC to a connector on the
CPU distribution panel (which also carries the console terminal connector, etc) and
then RL-RL cables from that to the first RL02 and between RL02s. Again, I don't
know if you call that an internal drive, the CPU is a separate rackmouting box,
the drive is another rackmounitng unit, but it was common to have 'packaged'
configurations of this machine, some of which included RL02s. from DEC.
Johnny
--
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: bqt at softjar.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
10:45 a.m.
[RL cables]
AFAIK that cable is purely a bus (i.e. no radial
per-drive wires), so you
should just be able to run it to the second connector, no issue. However,
I'm too lazy to check to make sure that's absolutely 100% accurate. :-)
It is just a bus. The internal drive cable is just a lenght of 40 wire ribbon cable
with 2 Berg sockets near one end and a single Berg socket at the other. The former
plug onto the backs of the external cable connectors. The latter plugs into a header
plug on the drive logic board.
There is one thing to be aware of. One of the 'corner' pins, I forget which one,
is
the +5V supply for the terminator. It is (obviously) not bused between drives. But
of course you do need to power the terminator. So if you make up an oddball
ribbon cable you should cut the appropriate wire between the controller and the
drive but leave it between the connector on the drive logic board and the conector
for the terminator.
[...]
> Not that I can even find a cable like that
anywhere currently...
RLOx cables of _any_ kind are very hard to find. There
are discussions under
way about making new ones; there is a supply (used) of the wierd-ass
connector that plugs into the back of the drive which could be used.
It's a pity you're not in the UK, I have some RL cabling bits in the spares box. I
could probably be persuaded to part with a twin-RL01 MINC....
-tony
3115
days inactive
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11 comments
6 participants
participants (6)
-
ard＠p850ug1.demon.co.uk -
ben＠bensinclair.com -
bqt＠update.uu.se -
ethan.dicks＠gmail.com -
glen.slick＠gmail.com -
jnc＠mercury.lcs.mit.edu