Hi folks,
I'm looking to build an X.25 packet data network for semi-active use
at the Connections Museum in Seattle. Please contact me off-list
(<astrid at xrtc.net>) if you have any X.25-capable networking gear
(routers, PADs, cable, etc) that wants a new home.
Why? Some of our newer equipment has serial management consoles.
Plumbing those into a proper-vintage data network would be a lot
spiffier than running around with usb-serial devices. I'm not looking
for serial-to-telnet IP converters.
I'm also interested in setting up a public federated X.25-over-TCP
network, much like https://ckts.info/ but for circuit switched data.
Cisco IOS 12 has support for DNS-based routing of XOT connections,
which I've been learning how to configure.
Thanks,
--
?strid smith (she/her)
=<[ c y b e r ]>=
antique telephone collectors association member #4870
> From: Barry M
> H960 120 lbs (not sure if this includes the side panels)
The H960 has a whole constellation of appurtenances which can add to the
weight: sides, back door, back mounting frame, top fan(s), floor screen,
stabilizer feet, etc, etc.
I happen to have an empty H960 (well, it does have the two top fans, which I
was too lazy to take out - they are only a couple of pounds each) out in my
garage, so I stuck it on a bathroom floor scale, and it seems to be about
100 pounds.
If you want the weight on any of the other bits (above), let me know, it
would be easy to weigh them.
Noel
> On May 23, 2021, at 9:14 PM, Marc Howard via cctech <cctech at classiccmp.org> wrote:
> In my case I'm looking for the weight of an RK05 and full height 19" DEC
> rack.
I have not see these published, but can attest that it is somewhere between 1 25-yr-old-can-load-in-station-wagon and 1 53-yr-old-can-load-in-station-wagon...
Marc,
I am not aware of a single document that lists the weights of various
sub-systems. I did find the weights or the RK05 and H960 rack:
RK05 110 lbs
See: DEC-00-RK05-DA RK05 DISK DRIVE MAINTENANCE MANUAL Page 1-2
H960 120 lbs (not sure if this includes the side panels)
See: DEC-11H45SM-E-D PDP-11/45 System Maintenance Manual Page C-5
--barrym
On Sun, May 23, 2021 at 10:15 PM Marc Howard via cctech <
cctech at classiccmp.org> wrote:
> Hi,
>
> Is there a doc anywhere that breaks out the individual weights of various
> PDP gear?
>
> In my case I'm looking for the weight of an RK05 and full height 19" DEC
> rack.
>
> Thanks,
>
> Marc
>
> On May 23, 2021, at 5:18 PM, Wayne S <wayne.sudol at hotmail.com> wrote:
>
> ISTR That the 2 main issues hindering wide spread adoption of TR was cost and and not knowing where TR development was headed.
> The Type 1 cabling needed to each port on the hub was expensive vs thick/thin Ethernet with taps (as were the hubs). Also, there was no second source for TR chips so everyone who wanted to make TR hardware was at the mercy of the IBM chip pricing so there weren?t too many TR cards being manufactured by anyone other than IBM. I recall the Madge TR cards for IBM ps/2 machines being about $400 ea circa 1992.
> So you had a lot of cost standing in the way if you were thinking about going/staying with TR and had hundreds of workstations.
There was also the bogus addressing and strange bridging.
> As for development, there was an ethernet roadmap ( don?t remember the group that put it together) stating that 100 mbit was next running over shielded twisted pair then unshielded tp. And 1000 mbit was possible.
> For TR, No one knew if IBM would up the speed past 16 mb and allow TR chips to be made cheaply.
>
> Also the fact that token passing is inherently slower than CSMA/CD did not help to sell TR.
> The analogy was that if you had a long street with many stop lights, using TR would be like having every light be red and having to stop at each light, where using Ethernet some of the lights would be green and no stop required.
>
> IBM tried to use that to their advantage and use to say since the amount of time it takes to token pass could be measured precisely that the network response as a whole could be determined and capacity planning was more deterministic using TR than Ethernet.
While at DEC in the network architecture group I contributed to a DEC marketing document that was a detailed point by point reply to an IBM document. IBM tried to claim TR was superior, we demolished that in detail. The deterministic argument was in there; unfortunately for IBM it is true that the network is deterministic -- has an upper bound on transmit latency -- but that upper bound is so crazy large that the property has no practical value whatsoever. BTW, this is where FDDI is vastly better, since it uses 802.4 timed token protocol rather than 802.5 token passing.
paul
> Is there a controller to attach an RS64 disk to a PDP-8? The only
> controller for the RS64 I can find is the UNIBUS RC11. Thanks.
I never saw any reply, so I gather the answer is 'no'. I looked through the
stuff on BitSavers for a bunch of other machines (IIRC, PDP-9 and PDP-12
and maybe one more), didn't see anything.
The odd thing is that based on the RS64 manual cover/format, it dates to the
same time period as the early -11's; and that manual is very careful to
separate the drive info from the controller. Very strange that it wasn't
interfaced to something else (like an -8 or -9). Maybe there was at one point
a plan to do so, but plans changed?
I note that there is an RS32 - I onder if they are any relation?
Noel
Is anyone familiar with the 4000/90 diagnostics? It looks like it will fail the test of the LCSPX graphics board, if it?s not plugged into a monitor, or is missing a loopback device. Is that correct?
T 2 fails, but the manual makes it sound like I need a loopback
T 100 succeeds when testing the LCSPX graphics board.
The system had been a boat anchor until a short time ago, as the battery in the Dallas DS1287A RTC was dead. Amazon just delivered two DS12887?s. Once I replaced it, it came right up. I was surprised to see I had a 4GB and a 2GB drive in it.
Now to dig out the mouse, and wait for the parts to hook it up to a monitor. :-)
Zane
Does anyone have experience using a SCSI2SD board to replace a Hard Drive on a VAXstation or an AlphaStation? I?m thinking about using them on some of my systems to reduce the amount of noise. I?ve gotten used to a quiet office. :-)
Zane
On 5/23/21 10:35 AM, Warner Losh wrote:
> I'm out in Brighton:)
Has it been wet there for you too for the last ~36 hours?
Are you suggesting splitzies on Rich's collection? Or is that a veiled
threat / invitation to share a beverage and chat? ;-)
--
Grant. . . .
unix || die
