On 1/1/22 2:44 PM, Guy Dunphy via cctalk wrote:
The 'installation and configuration' manual for this machine would be huge.
They don't have it.
On bitsavers. I just paged through it to check power
consumption.
Plus, it's a mainframe. Not even any blinkenlights. Without setting it up as
On 1/1/22 12:33 PM, Paul Koning via cctalk wrote:
And mainframes may use 3-phase power supplies; CDC 6000 mainframes do,
though with those it's 3 phase 400 Hz produced by motor-generators
(which in turn run off 3-phase mains power).
I know that some IBM mainframes prefer 3ɸ power but I know
The TU77 has a 3ɸ power plug on it. That probably explains why testing
it would be problematic in a residential settings.
A TU77 can run on household 240v. If I recall it used the 240 for the
big blower motor and the rest of the stuff ran on 110.
1ɸ240V is vastly different than 3ɸ120/208V.
In my current house I have done 240V/50A wiring, 240V/50A Sub Panel,
lots of 240V/30A outlets. None of which I would advise the usual
amateur to do. :-)
This is wise, but 240v is quite nice for computer equipment. I had an
electrician run a 240v 30a (10g wire) circuit out to my work shed,
> On Jan 1, 2022, at 4:19 PM, Josh Dersch via cctalk
> wrote:
>
> On Sat, Jan 1, 2022 at 12:47 PM Guy Dunphy via cctalk
> wrote:
>
>> ...
>> But you're all focussed on that, and missing another important detail. The
>> machine has a liquid cooling system.
>> ...
>
> For clarification --
On 1/1/22 2:35 PM, ben via cctalk wrote:
On 2022-01-01 12:36 p.m., Jon Elson via cctalk wrote:
On 1/1/22 1:11 PM, Bill Gunshannon via cctalk wrote:
Just out of curiosity, how much current is needed for an
11/780?
Depending on options, the CPU cabinet would draw about
10-12 A per line,
On 1/1/22 3:19 PM, Josh Dersch via cctalk wrote:
For clarification -- the 11/780 is not liquid cooled. The seller mixed up
some photos between the TU77 listing and the 11/780 listing (the TU77
listing has photos of the 11/780's backplane in it just to make things more
fun). Agreed on all
Found here:
http://www.pdp8online.com/bklatt/43.jpg
Digital Cables Handbook
Nigel Johnson, MSc., MIEEE, MCSE VE3ID/G4AJQ/VA3MCU
Amateur Radio, the origin of the open-source concept!
Skype: tilbury2591nw.john...@ieee.org
On 2022-01-01 18:52, Ethan Dicks via cctalk wrote:
On Sat, Jan 1,
Quick question: I'm going through my old cables looking for the paddle
interface for the Current loop for my pdp8/L. I thought I saved one from
my old pdp8/I, maybe not.
Regardless, I found a M857 board with a RS232 cable on it and BC01R-25
on it. Was that for a pdp11/05 by chance?
Oddly
On Sat, Jan 1, 2022 at 6:40 PM Chris Zach via cctalk
wrote:
> Regardless, I found a M857 board with a RS232 cable on it and BC01R-25
> on it. Was that for a pdp11/05 by chance?
I found this reference from the Cables Handbook. Sounds like it was a
generic cable that probably worked with several
On Sat, Jan 1, 2022, 7:03 PM Nigel Johnson Ham via cctalk <
cctalk@classiccmp.org> wrote:
> Found here:
>
> http://www.pdp8online.com/bklatt/43.jpg
https://www.vintagecomputer.net/browse_thread.cfm?id=249
Bill
>
>
On 1/1/22 1:40 PM, Paul Koning via cctalk wrote:
On Jan 1, 2022, at 1:12 PM, Noel Chiappa via cctalk
wrote:
This:
https://www.ebay.com/itm/275084268137
The starting price is expensive, but probably not utterly unreasonable,
given that:
- the 780 was the first VAX, and thus
On 1/1/22 11:49 AM, Jonathan Chapman via cctalk wrote:
Indeed, Tuscon Buying Group deals in a lot of industrial stuff --
we buy from them at $day_job sometimes. I'd be really surprised if
they don't have 240V available for testing somewhere in their shop.
There's a difference in having
On 1/1/22 11:49 AM, John H. Reinhardt via cctalk wrote:
TU77: https://www.ebay.com/itm/275083502085 (The 11/780 is visible in
the background of the first picture)
The TU77 has a 3ɸ power plug on it. That probably explains why testing
it would be problematic in a residential settings.
On 1/1/22 12:17 PM, Dennis Boone via cctalk wrote:
IIRC nothing in the VAX cpu actually requires 3 phase. The PDU(s)
just eat that from the wall.
I think that's the same with all the /computer/ equipment that I've seen
which connects to 3ɸ power. A single phase could be used for all of it.
> On Jan 1, 2022, at 2:21 PM, Grant Taylor via cctalk
> wrote:
>
> On 1/1/22 12:17 PM, Dennis Boone via cctalk wrote:
>> IIRC nothing in the VAX cpu actually requires 3 phase. The PDU(s) just eat
>> that from the wall.
>
> I think that's the same with all the /computer/ equipment that
>
True. But if you're trying to get > $5000 for something, it doesn't seem
unreasonable to suggest that investing a bit in getting an extension cord run
to the location of the machine would be a good idea. The absence of that
effort makes me wonder if the owner knows what the outcome of such
On 1/1/22 12:44 PM, Paul Koning via cctalk wrote:
Could be. For the CDC case, I see actual 3-phase DC supplies, i.e.,
3 phase bridge rectifiers fed by 3-phase transformers.
Interesting. That brings to mind 6ɸ DC supplies. -- Two typical 3ɸ
rectifier networks (making DC pulses be 60°
On Sat, Jan 1, 2022 at 11:55 AM W2HX via cctalk
wrote:
> >
> True. But if you're trying to get > $5000 for something, it doesn't seem
> unreasonable to suggest that investing a bit in getting an extension cord
> run to the location of the machine would be a good idea. The absence of
> that
On 2022-01-01 12:36 p.m., Jon Elson via cctalk wrote:
On 1/1/22 1:11 PM, Bill Gunshannon via cctalk wrote:
Just out of curiosity, how much current is needed for an 11/780?
Depending on options, the CPU cabinet would draw about 10-12 A per line,
3-Phase 208 V. And, that is on the upper end
This:
https://www.ebay.com/itm/275084268137
The starting price is expensive, but probably not utterly unreasonable,
given that:
- the 780 was the first VAX, and thus historically important
- 780's are incredibly rare; this is the first one I recall seeing for sale
in the classic computer
> On Jan 1, 2022, at 1:12 PM, Noel Chiappa via cctalk
> wrote:
>
> This:
>
>https://www.ebay.com/itm/275084268137
>
> The starting price is expensive, but probably not utterly unreasonable,
> given that:
>
> - the 780 was the first VAX, and thus historically important
>
> - 780's are
> this is the first one I recall seeing for sale
> in the classic computer era (versus several -11/70's, /40s, etc)
Last one that went auction-style on eBay went for $1,178.00, local pick-up. I
know the buyer.
I still wouldn't think $5K is totally unreasonable, given the clean condition
and
On 1/1/2022 12:40 PM, Paul Koning via cctalk wrote:
On Jan 1, 2022, at 1:12 PM, Noel Chiappa via cctalk
wrote:
This:
https://www.ebay.com/itm/275084268137
The starting price is expensive, but probably not utterly unreasonable,
given that:
- the 780 was the first VAX, and thus
> I have questions
>
> Where are you getting two /different/ phases? -- Remember, the
> different legs on residential 120/240 wiring are really the same single
> phase.
They're 180 degrees out. Sufficiently different for a number of applications,
but certainly not all!
Thanks,
Jonathan
On 1/1/22 1:56 PM, W2HX via cctalk wrote:
The other benefit to 3phase power to something like a computer is that the
filter caps required can be much smaller. Once you rectify three phases 60* you
get MUCH less ripple because every 60 degrees you have a new peak arriving.
When you have a real
On Sat, Jan 1, 2022 at 12:47 PM Guy Dunphy via cctalk
wrote:
> At 07:50 PM 1/01/2022 +, you wrote:
> >>
> >True. But if you're trying to get > $5000 for something, it doesn't seem
> unreasonable to suggest that investing a bit in getting an extension cord
> run to the location of the
On 1/1/22 10:40 AM, Paul Koning via cctalk wrote:
On Jan 1, 2022, at 1:12 PM, Noel Chiappa via cctalk
wrote:
This:
https://www.ebay.com/itm/275084268137
The starting price is expensive, but probably not utterly unreasonable,
given that:
- the 780 was the first VAX, and thus
On 1/1/22 11:46 AM, Bill Gunshannon via cctalk wrote:
Having 240 in your house does not necessarily mean you have 240 outlets
anywhere and not everyone is capable of doing their own house wiring.
There may even be 240 V outlets but not available when / where needed.
E.g. in use (stove, dryer,
On 1/1/22 11:51 AM, Paul Koning via cctalk wrote:
True. But if you're trying to get > $5000 for something, it doesn't
seem unreasonable to suggest that investing a bit in getting an
extension cord run to the location of the machine would be a good idea.
The absence of that effort makes me
On 1/1/22 1:53 PM, Grant Taylor via cctalk wrote:
On 1/1/22 11:46 AM, Bill Gunshannon via cctalk wrote:
Having 240 in your house does not necessarily mean you have 240
outlets anywhere and not everyone is capable of doing their own house
wiring.
There may even be 240 V outlets but not
On 1/1/22 12:51 PM, Paul Koning via cctalk wrote:
True. But if you're trying to get > $5000 for something, it doesn't seem
unreasonable to suggest that investing a bit in getting an extension cord run to
the location of the machine would be a good idea. The absence of that effort
makes
On 1/1/2022 1:10 PM, Jon Elson via cctalk wrote:
On 1/1/22 12:12 PM, Noel Chiappa via cctalk wrote:
This:
https://www.ebay.com/itm/275084268137
The starting price is expensive, but probably not utterly unreasonable,
given that:
They don't have a front picture, but there is a rear
On 1/1/22 1:11 PM, Bill Gunshannon via cctalk wrote:
Just out of curiosity, how much current is needed for an
11/780?
Depending on options, the CPU cabinet would draw about 10-12
A per line, 3-Phase 208 V. And, that is on the upper end of
the range. Starting surge would be a lot more,
Sorta nitpick, but:
> 3-phase 208/240 V WYE power
Not a thing. It's 120/208Y or 240 delta, high leg or not. Nameplates suggest
120/208Y which is the most common "not a machine shop" configuration.
Thanks,
Jonathan
On 1/1/22 12:59 PM, Jonathan Chapman via cctalk wrote:
They're 180 degrees out. Sufficiently different for a number of
applications, but certainly not all!
They are 180° out of phase with respect to each other. But they are the
same single phase when viewed by anything outside of them.
It splits the input 3 phase 120/208 30A input to separate 120V circuits.
3*30A 120V circuits if you want. Mine used about 3KVA, so it'll actually
(just barely) run off of a single 30A/120V or multiple 15/20A 120V circuits
if you rewire the input a bit.
Patrick Finnegan
On Sat, Jan 1, 2022, 14:11
> On Jan 1, 2022, at 3:08 PM, Grant Taylor via cctalk
> wrote:
>
> On 1/1/22 12:44 PM, Paul Koning via cctalk wrote:
>> ...
>> And of course 400 Hz gave them an additional advantage in reduced
>> transformer size and reduced ripple (for a given filter capacitor).
>
> I was going to ask how
On 1/1/22 1:50 PM, W2HX via cctalk wrote:
True. But if you're trying to get > $5000 for something, it doesn't seem
unreasonable to suggest that investing a bit in getting an extension cord run to
the location of the machine would be a good idea. The absence of that effort
makes me wonder if
> On Jan 1, 2022, at 1:46 PM, Bill Gunshannon via cctalk
> wrote:
>
> On 1/1/22 1:40 PM, Paul Koning via cctalk wrote:
>>> On Jan 1, 2022, at 1:12 PM, Noel Chiappa via cctalk
>>> wrote:
>>>
>>> This:
>>>
>>>https://www.ebay.com/itm/275084268137
>>>
>>> The starting price is
On 1/1/22 12:12 PM, Noel Chiappa via cctalk wrote:
This:
https://www.ebay.com/itm/275084268137
The starting price is expensive, but probably not utterly unreasonable,
given that:
They don't have a front picture, but there is a rear picture
of a TU-77/TU-78 tape drive interior.
As for
> In my current house I have done 240V/50A wiring, 240V/50A Sub Panel,
> lots of 240V/30A outlets. None of which I would advise the usual
> amateur to do. :-)
IIRC nothing in the VAX cpu actually requires 3 phase. The PDU(s) just
eat that from the wall.
De
> I think that's the same with all the /computer/ equipment that I've seen
> which connects to 3ɸ power. A single phase could be used for all of it.
Computer exist which require three phase at a unit power supply level. It's
often also used for large blowers if the cabinet(s) don't strictly
> On Jan 1, 2022, at 2:38 PM, Grant Taylor via cctalk
> wrote:
>
> On 1/1/22 12:33 PM, Paul Koning via cctalk wrote:
>> And mainframes may use 3-phase power supplies; CDC 6000 mainframes do,
>> though with those it's 3 phase 400 Hz produced by motor-generators (which in
>> turn run off
> I know that some IBM mainframes prefer 3ɸ power but I know of multiple
> people that have re-wired their CECs to use 1ɸ power.
My Multiprise 2003/205 claims to want a pair of 3-phase inputs. I've
run it on two "phases" on a single side. It bitches, of course, and one
loses the intended
On 1/1/22 12:43 PM, Dennis Boone via cctalk wrote:
My Multiprise 2003/205 claims to want a pair of 3-phase inputs.
Is it assumed that those 2 x 3ɸ inputs are feed from different paths,
thus path redundancy? I'd think that the phases would be the same.
I've run it on two "phases" on a
The other benefit to 3phase power to something like a computer is that the
filter caps required can be much smaller. Once you rectify three phases 60* you
get MUCH less ripple because every 60 degrees you have a new peak arriving.
When you have a real gas (electron) guzzler like one of these,
At 07:50 PM 1/01/2022 +, you wrote:
>>
>True. But if you're trying to get > $5000 for something, it doesn't seem
>unreasonable to suggest that investing a bit in getting an extension cord run
>to the location of the machine would be a good idea. The absence of that
>effort makes me wonder
> Way more because of inertia. Not quite a UPS, but short power glitches enough
> to blink the computer room lights are not going to be seen by the mainframe.
Indeed, one can purchase flywheel systems to ride through genset startup time
on inertia!
Thanks,
Jonathan
TU77: https://www.ebay.com/itm/275083502085 (The 11/780 is visible in
That looks complete with the TM03 formatter.
RM05: https://www.ebay.com/itm/284587865252
That looks like it's missing the MassBus adapter. I think two RM05's
shared a cabinet between them that contained the MBA logic. Not
On 1/1/22 2:00 PM, Chris Zach via cctalk wrote:
This is wise, but 240v is quite nice for computer equipment. I had an
electrician run a 240v 30a (10g wire) circuit out to my work shed, where
a subpanel is installed with 120v 15a and 240v 15a circuits for the
equipment.
I had two 120v 20A
Can anyone help me to understand why all my RF30 disks report the same
diagnostic code 0x300B?
Thanks
Rob
> -Original Message-
> From: Rob Jarratt
> Sent: 23 December 2021 17:46
> To: r...@jarratt.me.uk; 'Rob Jarratt' ;
'General
> Discussion: On-Topic and Off-Topic Posts'
> Subject:
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