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Re: What is the oldest computer that could be used today for real work? [message #411251 is a reply to message #411247] Sat, 25 September 2021 07:19 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: J. Clarke

On 25 Sep 2021 04:22:50 -0300, Mike Spencer
<mds@bogus.nodomain.nowhere> wrote:

>
> J. Clarke <jclarke.873638@gmail.com> writes:
>
>> On 24 Sep 2021 03:10:29 -0300, Mike Spencer
>> <mds@bogus.nodomain.nowhere> wrote:
>>
>>> AIUI, the US Navy now navigates with Windoes, has for many years. And
>>> in addition has dropped astral navigation skills as a requirement for
>>> officers. Furrfu.
>>
>> You do know that a handheld GPS can provide the same information as
>> celestial nav, with vastly greater precision, do you not? And likely
>> has accurate charts these days.
>
> Yes, I do know that. But the US Navy operates *war*ships. If the
> Navy is ever again confronted with an actual war -- something beyond
> sending helicopter gunships or drones after "insurgents" or showing
> the flag in the South China Sea -- against a capable opponent,
> GPS/satnav is going to be the opponent's early target. Naval mariners
> have long had the attitude that they should be prepared to cope when X
> fails for almost all values of X.

Satnav isn't that easy to kill you know. It's not like you can shoot
one down with a MiG 21. Besides, there are 4 different systems. To
render satnav unusable would require destroying upwards of 100
different satellites.

In addition, google SINS. Have you asked yourself how a submarine
could sail around the world submerged in 1960? The answer is inertial
navigation. It's not as precise as GPS--you can't use it to enter a
harbor in a fog after 25,000 miles--but it works well enough if you
are aware of its limitations.

> I once toured a Canadian naval ship and asked about a hand-crank
> bolted to a bulkhead in a hold near the bilges. The answer: If you
> have a cold ship -- boilers cold, no shore power, nothing operating --
> you unbolt the crank, use it to hand-start an antique single-banger
> diesel. That generates enough power to start the big 8-cyl diesel
> which in turn compresses enough air to start the two really big
> 16-cyl diesels which then generate enough power to fire up and run
> everything else.
Re: What is the oldest computer that could be used today for real work? [message #411273 is a reply to message #411223] Sat, 25 September 2021 15:28 Go to previous messageGo to next message
Peter Flass is currently offline  Peter Flass
Messages: 7973
Registered: December 2011
Karma: 0
Senior Member
J. Clarke <jclarke.873638@gmail.com> wrote:
> On 24 Sep 2021 03:10:29 -0300, Mike Spencer
> <mds@bogus.nodomain.nowhere> wrote:
>
>>
>> J. Clarke <jclarke.873638@gmail.com> writes:
>>
>>> On Thu, 23 Sep 2021 18:31:34 GMT, Charlie Gibbs
>>> <cgibbs@kltpzyxm.invalid> wrote:
>>>
>>>> On 2021-09-23, Scott Lurndal <scott@slp53.sl.home> wrote:
>>>>
>>>> > Running critical infrastructure on windows should be a criminal offense.
>>>>
>>>> Hear, hear!
>>>
>>> That ship, however, has sailed.
>>
>> AIUI, the US Navy now navigates with Windoes, has for many years. And
>> in addition has dropped astral navigation skills as a requirement for
>> officers. Furrfu.
>
> You do know that a handheld GPS can provide the same information as
> celestial nav, with vastly greater precision, do you not? And likely
> has accurate charts these days.
>

Sure, but only, as someone has said, if the satellites are working. Heck,
my iPhone has good GPS.

--
Pete
Re: What is the oldest computer that could be used today for real work? [message #411276 is a reply to message #411273] Sat, 25 September 2021 15:56 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: J. Clarke

On Sat, 25 Sep 2021 12:28:22 -0700, Peter Flass
<peter_flass@yahoo.com> wrote:

> J. Clarke <jclarke.873638@gmail.com> wrote:
>> On 24 Sep 2021 03:10:29 -0300, Mike Spencer
>> <mds@bogus.nodomain.nowhere> wrote:
>>
>>>
>>> J. Clarke <jclarke.873638@gmail.com> writes:
>>>
>>>> On Thu, 23 Sep 2021 18:31:34 GMT, Charlie Gibbs
>>>> <cgibbs@kltpzyxm.invalid> wrote:
>>>>
>>>> > On 2021-09-23, Scott Lurndal <scott@slp53.sl.home> wrote:
>>>> >
>>>> >> Running critical infrastructure on windows should be a criminal offense.
>>>> >
>>>> > Hear, hear!
>>>>
>>>> That ship, however, has sailed.
>>>
>>> AIUI, the US Navy now navigates with Windoes, has for many years. And
>>> in addition has dropped astral navigation skills as a requirement for
>>> officers. Furrfu.
>>
>> You do know that a handheld GPS can provide the same information as
>> celestial nav, with vastly greater precision, do you not? And likely
>> has accurate charts these days.
>>
>
> Sure, but only, as someone has said, if the satellites are working. Heck,
> my iPhone has good GPS.

Why would they not be? There are 100 orbital launches or so a year.
It would take that many to knock down all the satnav satellites. And
there aren't very many orbital launch facilities in the
world--furthermore none of them are hardened.
Re: What is the oldest computer that could be used today for real work? [message #411278 is a reply to message #411276] Sat, 25 September 2021 17:21 Go to previous messageGo to next message
Ahem A Rivet's Shot is currently offline  Ahem A Rivet's Shot
Messages: 4471
Registered: January 2012
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Senior Member
On Sat, 25 Sep 2021 15:56:30 -0400
J. Clarke <jclarke.873638@gmail.com> wrote:

> Why would they not be? There are 100 orbital launches or so a year.
> It would take that many to knock down all the satnav satellites. And
> there aren't very many orbital launch facilities in the
> world--furthermore none of them are hardened.

This and the possibility that there is a separate constellation for
military use with an authenticated and encrypted protocol and hardened
satellites. It would be easy enough to do and hide and an elementary common
sense precaution and it's really hard to steal a private key if the only
copy is on a satellite.

--
Steve O'Hara-Smith
Odds and Ends at http://www.sohara.org/
Re: What is the oldest computer that could be used today for real work? [message #411279 is a reply to message #410772] Sat, 25 September 2021 19:48 Go to previous messageGo to next message
lawrence is currently offline  lawrence
Messages: 105
Registered: July 2012
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Senior Member
Grant Taylor <gtaylor@tnetconsulting.net> writes:

> On 9/6/21 2:14 AM, Ahem A Rivet's Shot wrote:
>> Erm KA9Q was originally TCP/IP over souped up RTTY (aka packet
>> radio) was it not. OK it was not Linux (that was still in the
>> future) but it did come with email, usenet, ftp and a multi-tasking
>> kernel to run them under messy dos - I never saw the CP/M version
>> but 64K is awfully tight for TCP/IP.
>
> Was it Usenet (UUCP / NNTP) or FTP proper? Or was it other
> non-standard services that provided similar function to the proper
> services?
>

It was a full TCP/IP stack for late-80s-vintage IBM PC Hardware. The
'dominant' transport was IP-over-AX.25, but it also could use early
Ethernet drivers, and there was a version that supported SL/IP (but I
don't recall ever seeing a PPP implementation)

It included 'application' support for FTP, SMTP transport,a mail
client called Bdale's Mailer, and a complete TELNET client
implementation. It also provided a keyboard-to-keyboard-chat feature as
a TELNET server.

--NK1G
Re: What is the oldest computer that could be used today for real work? [message #411283 is a reply to message #410715] Sun, 26 September 2021 00:24 Go to previous messageGo to next message
Charlie Gibbs is currently offline  Charlie Gibbs
Messages: 5048
Registered: January 2012
Karma: 0
Senior Member
On 2021-09-25, Andreas Kohlbach <ank@spamfence.net> wrote:

> On Sat, 25 Sep 2021 07:19:54 -0400, J. Clarke wrote:
>>
>> On 25 Sep 2021 04:22:50 -0300, Mike Spencer
>> <mds@bogus.nodomain.nowhere> wrote:
>>
>>> Yes, I do know that. But the US Navy operates *war*ships. If the
>>> Navy is ever again confronted with an actual war -- something beyond
>>> sending helicopter gunships or drones after "insurgents" or showing
>>> the flag in the South China Sea -- against a capable opponent,
>>> GPS/satnav is going to be the opponent's early target. Naval mariners
>>> have long had the attitude that they should be prepared to cope when X
>>> fails for almost all values of X.
>>
>> Satnav isn't that easy to kill you know. It's not like you can shoot
>> one down with a MiG 21. Besides, there are 4 different systems. To
>> render satnav unusable would require destroying upwards of 100
>> different satellites.
>
> From what I read there are 31 (US) GPS satellites in orbit. Cannot find
> out the distance to one to another. Might be less than 1000
> kilometers. If one nuke is fired at a distance of 500 kilometers between
> two satellites it might take out both of them. So you (China, or who ever
> is the enemy in a future war) need 15 nukes to take out the whole
> system. Shouldn't be a problem. Should be even enough to take down only a
> few of them to make the system useless.

Not really. If you can pick up three satellites you have a 2D position.
Four satellites will give you a 3D position. Five will give you RAIM
(redundant autonomous integrity monitoring). As long as you have that
much of a subset in view, you can still navigate, although perhaps at
reduced precision.

Occasionally NOTAMs (notices to airmen) are issued warning about possible
interruptions to GPS service. They specify a time range when GPS signals
may become unreliable within a certain radius of a given spot (smaller
radii at low altitudes, larger ones at higher altitudes). The specified
location is always at a military base; they're experimenting with jamming
the signals.

--
/~\ Charlie Gibbs | Life is perverse.
\ / <cgibbs@kltpzyxm.invalid> | It can be beautiful -
X I'm really at ac.dekanfrus | but it won't.
/ \ if you read it the right way. | -- Lily Tomlin
Re: What is the oldest computer that could be used today for real work? [message #411284 is a reply to message #411234] Sun, 26 September 2021 00:24 Go to previous messageGo to next message
Charlie Gibbs is currently offline  Charlie Gibbs
Messages: 5048
Registered: January 2012
Karma: 0
Senior Member
[top-posting corrected]

On 2021-09-25, Branimir Maksimovic <branimir.maksimovic@gmail.com> wrote:

> On 2021-09-24, maus <maus@dmaus.org> wrote:
>
>> I occasion get a message demainding money or else. So far, nothing
>> happens.
>
> I have learned that NOTHING IS FREE. If you PAY HONESTLY it is cheaper
> then to use something virtually free.

If they CHARGE HONESTLY I'd more likely to pay.

--
/~\ Charlie Gibbs | Life is perverse.
\ / <cgibbs@kltpzyxm.invalid> | It can be beautiful -
X I'm really at ac.dekanfrus | but it won't.
/ \ if you read it the right way. | -- Lily Tomlin
Re: What is the oldest computer that could be used today for real work? [message #411288 is a reply to message #411283] Sun, 26 September 2021 03:10 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: Branimir Maksimovic

On 2021-09-26, Charlie Gibbs <cgibbs@kltpzyxm.invalid> wrote:
>
> Not really. If you can pick up three satellites you have a 2D position.
> Four satellites will give you a 3D position. Five will give you RAIM
> (redundant autonomous integrity monitoring). As long as you have that
> much of a subset in view, you can still navigate, although perhaps at
> reduced precision.
>
> Occasionally NOTAMs (notices to airmen) are issued warning about possible
> interruptions to GPS service. They specify a time range when GPS signals
> may become unreliable within a certain radius of a given spot (smaller
> radii at low altitudes, larger ones at higher altitudes). The specified
> location is always at a military base; they're experimenting with jamming
> the signals.
>
Not really jonosfere, you need only one.
Also, who first build Tesla Weapon planes will became thing of the past.
Also to improve radar for detecting objects that does not reflect signals
from 20km range...

--

7-77-777
Evil Sinner!
Re: What is the oldest computer that could be used today for real work? [message #411289 is a reply to message #411284] Sun, 26 September 2021 03:19 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: Branimir Maksimovic

On 2021-09-26, Charlie Gibbs <cgibbs@kltpzyxm.invalid> wrote:
>> I have learned that NOTHING IS FREE. If you PAY HONESTLY it is cheaper
>> then to use something virtually free.
>
> If they CHARGE HONESTLY I'd more likely to pay.
>
Well, in 2000 I gave away all my money, thrhoughed
last 1600deutch marks behind left shoulder for luck,
and started to sleep on streets :P
In order to test theory how you can reach Kingdom Of Heaven :P
I despise money :P
Think it is ANTICHRIST :P
When I want to buy small chocolate that costs less then
1 euro, I pay 40, and when seller runs for me I say:
keep it sister, you *earned it*.
I beleive that if you are alum it will be taken from you,
but i fyou don't care and trow away you will be *given*
more then you need :P


--

7-77-777
Evil Sinner!
Re: What is the oldest computer that could be used today for real work? [message #411294 is a reply to message #411283] Sun, 26 September 2021 12:10 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: J. Clarke

On Sun, 26 Sep 2021 04:24:58 GMT, Charlie Gibbs
<cgibbs@kltpzyxm.invalid> wrote:

> On 2021-09-25, Andreas Kohlbach <ank@spamfence.net> wrote:
>
>> On Sat, 25 Sep 2021 07:19:54 -0400, J. Clarke wrote:
>>>
>>> On 25 Sep 2021 04:22:50 -0300, Mike Spencer
>>> <mds@bogus.nodomain.nowhere> wrote:
>>>
>>>> Yes, I do know that. But the US Navy operates *war*ships. If the
>>>> Navy is ever again confronted with an actual war -- something beyond
>>>> sending helicopter gunships or drones after "insurgents" or showing
>>>> the flag in the South China Sea -- against a capable opponent,
>>>> GPS/satnav is going to be the opponent's early target. Naval mariners
>>>> have long had the attitude that they should be prepared to cope when X
>>>> fails for almost all values of X.
>>>
>>> Satnav isn't that easy to kill you know. It's not like you can shoot
>>> one down with a MiG 21. Besides, there are 4 different systems. To
>>> render satnav unusable would require destroying upwards of 100
>>> different satellites.
>>
>> From what I read there are 31 (US) GPS satellites in orbit. Cannot find
>> out the distance to one to another. Might be less than 1000
>> kilometers. If one nuke is fired at a distance of 500 kilometers between
>> two satellites it might take out both of them. So you (China, or who ever
>> is the enemy in a future war) need 15 nukes to take out the whole
>> system. Shouldn't be a problem. Should be even enough to take down only a
>> few of them to make the system useless.
>
> Not really. If you can pick up three satellites you have a 2D position.
> Four satellites will give you a 3D position. Five will give you RAIM
> (redundant autonomous integrity monitoring). As long as you have that
> much of a subset in view, you can still navigate, although perhaps at
> reduced precision.
>
> Occasionally NOTAMs (notices to airmen) are issued warning about possible
> interruptions to GPS service. They specify a time range when GPS signals
> may become unreliable within a certain radius of a given spot (smaller
> radii at low altitudes, larger ones at higher altitudes). The specified
> location is always at a military base; they're experimenting with jamming
> the signals.

In addition to what Charlie says:

There are four constellations. We have one, Russia has one, the EU
has one, and China has one. India is working on one. In a war in
which the US is involved, we can count on access to at least two of
those.

Andreas could not find out the distance between the satellites because
there is no fixed distance. They are in 6 orbital planes with 4 or
more satellites per plane, at an orbital radius of roughly 16503
miles. The gory details can be found in
https://www.gps.gov/technical/ps/2020-SPS-performance-standa rd.pdf.
You may find
https://www.faa.gov/about/office_org/headquarters_offices/av s/offices/aam/cami/library/online_libraries/aerospace_medici ne/tutorial/media/iii.4.1.4_describing_orbits.pdf
helpful in understanding the nomenclature used.

Calculating the actual closest approach is more effort than I want to
go into for a casual conversation. For a rough estimate of the
distance between them consider a sphere of radius 16503 miles. That
has an area of 3,422,438,583 square miles. Divide that by 24 and you
get 142601607 square miles per satellite. Figure the radius of a
circle of that area and you get 6737. Double that and you have 13474
miles. Very very rough estimate, and will vary.

Next, there's the notion of using a nuclear weapon to kill two
satellites. Let's look at that. Assume the weapon yield is 60
megatons. The largest nuclear weapon ever demonstrated (Tsar Bomba,
Soviet test AN602) had a yield of 50-58 megatons depending on whose
data you believe so that is a reasonable limit. There are no currently
operational launch systems which could carry a weapon that size to the
altitude required to attack GPS.

Blast effects. In air the overpressure at 40 miles would be down to 1
psi. At that overpressure breaking windows is the major effect.
That's in air--space is a vacuum so the blast effects occur over a
much smaller radius.

Thermal effects: Beyond 50 miles the thermal intensity is enough to
produce a sunburn in humans.

Radiation: A Tsar Bomba sized weapon could produce enough radiation
to damage unshielded rad-hard ICs at up to about 7500 miles. The
amount of shielding installed on GPS satellites does not appear to be
available in unclassified documents. At the

EMP:
This is the one that people always trot out. EMP is an atmospheric
effect--it is the result of interaction of the nuclear weapon with
both the magnetic field and the atmosphere and depends on gamma rays
stripping electrons from atoms in the atmosphere. Its nature is that
it is directed downward, not upward and there's not enough atmosphere
at the altitude of GPS satellites to generate an effective E1 or E2
pulse at their altitude. An E3 pulse could still occur but it
requires very long transmission lines to have an effect, and that is
something that satellites do not have.

Intensification of the Van Allen Belt:
This is something that was demonstrated in several US and Soviet
nuclear tests. It is not an issue for GPS as they are above the lower
belt and below the upper one.

Bottom line:
Trying to take out two satellites with one nuclear weapon is unlikely
to take out either and would require a Starship/Long March 9/Saturn
V/N1 class launch vehicle, none of which exist in operational form at
this time. And if there is to be more than 1 such attempt there will
have to be hardened silos for such vehicles, which again do not exist
anywhere at this time--after the first attempt the launch facility
would become a priority target.

Note also that ICBMs are not designed to attack satellites. They
could be repurposed to do so but it would require essentially
reworking them into orbital launchers and their payload would be
significantly reduced.
Re: What is the oldest computer that could be used today for real work? [message #411295 is a reply to message #411284] Sun, 26 September 2021 12:11 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: J. Clarke

On Sun, 26 Sep 2021 04:24:59 GMT, Charlie Gibbs
<cgibbs@kltpzyxm.invalid> wrote:

> [top-posting corrected]
>
> On 2021-09-25, Branimir Maksimovic <branimir.maksimovic@gmail.com> wrote:
>
>> On 2021-09-24, maus <maus@dmaus.org> wrote:
>>
>>> I occasion get a message demainding money or else. So far, nothing
>>> happens.
>>
>> I have learned that NOTHING IS FREE. If you PAY HONESTLY it is cheaper
>> then to use something virtually free.
>
> If they CHARGE HONESTLY I'd more likely to pay.

While the money to develop Linux comes from somewhere, nobody is
obligated to pay for it.
Re: What is the oldest computer that could be used today for real work? [message #411296 is a reply to message #411279] Sun, 26 September 2021 12:55 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: Grant Taylor

On 9/25/21 5:48 PM, Lawrence Statton (NK1G) wrote:
> It was a full TCP/IP stack for late-80s-vintage IBM PC Hardware.
> The 'dominant' transport was IP-over-AX.25, but it also could use
> early Ethernet drivers, and there was a version that supported SL/IP
> (but I don't recall ever seeing a PPP implementation)

Thank you for the clarification Lawrence.

I had wondered if you might be referring to similar functionality that
many BBS packages provided using different technology. But you have
satisfactorily clarified my misunderstanding.

> It included 'application' support for FTP, SMTP transport,a mail client
> called Bdale's Mailer, and a complete TELNET client implementation.
> It also provided a keyboard-to-keyboard-chat feature as a TELNET
> server.

Interesting.

Thank you again.



--
Grant. . . .
unix || die
Re: What is the oldest computer that could be used today for real work? [message #411299 is a reply to message #411279] Sun, 26 September 2021 15:50 Go to previous messageGo to next message
John Levine is currently offline  John Levine
Messages: 1299
Registered: December 2011
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Senior Member
According to Lawrence Statton (NK1G) <lawrence@cluon.com>:
> [KA9Q] was a full TCP/IP stack for late-80s-vintage IBM PC Hardware. The
> 'dominant' transport was IP-over-AX.25, but it also could use early
> Ethernet drivers, and there was a version that supported SL/IP (but I
> don't recall ever seeing a PPP implementation)

In 1990 I used a couple of old PCs and Wavelan proto-wifi cards to set up a connection
from my house in Cambridge MA to a friend's house a block away and share his connection
to the local Internet co-op. It was quite the kludge, with a yagi antenna sticking out
of an attic window but it worked great.

I believe I used PC-ROUTE, packet drivers for the Ethernet card and perhaps an NDIS
shim for the Wavelan, but I don't think I had to write any software.

--
Regards,
John Levine, johnl@taugh.com, Primary Perpetrator of "The Internet for Dummies",
Please consider the environment before reading this e-mail. https://jl.ly
Re: What is the oldest computer that could be used today for real work? [message #411311 is a reply to message #411221] Mon, 27 September 2021 08:52 Go to previous messageGo to next message
cross is currently offline  cross
Messages: 9
Registered: May 2013
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Junior Member
In article <2fkskgluiu6o31kjfcgsmbh28m4jrek0bq@4ax.com>,
J. Clarke <jclarke.873638@gmail.com> wrote:
> On Fri, 24 Sep 2021 19:13:06 -0000 (UTC),
> cross@spitfire.i.gajendra.net (Dan Cross) wrote:
>> Sure it is. The level of difficulty depends entirely on
>> your processes and practices and how robust your test and
>> staging infrastructure is. Some places do it very well.
>> Others, not so much.
>
> If you feel like robusticizing the "processes and practices and test
> and staging infrastructure" for a Fortune 500 financial services
> company, I can give you a name to which you can send your sales pitch.
> Make it shiny enough and put a big enough hook in it and he may even
> bite.

So you admit that those processes and practices are below
those of industry standards in more modern organizations.
Cool.

- Dan C.
Re: What is the oldest computer that could be used today for real work? [message #411333 is a reply to message #410715] Tue, 28 September 2021 09:10 Go to previous messageGo to next message
usenet is currently offline  usenet
Messages: 555
Registered: May 2013
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Senior Member
On Fri, 24 Sep 2021 20:23:33 -0500, Dave Garland <dave.garland@wizinfo.com>
wrote:
> On 9/24/2021 5:50 PM, J. Clarke wrote:
>> You do know that a handheld GPS can provide the same information as
>> celestial nav, with vastly greater precision, do you not? And likely
>> has accurate charts these days.
>>
> Works so long as the satellites are still functioning, not turned off,
> not jammed, not spoofed. Remember a few years ago Iran fooled a US
> drone into landing at one of their airfields? Or google "China GPS
> spoofing" for fun and games with ships near to China. Or the 20 ships
> in the Black Sea in 2017 whose location returned as an airport 32km
> inland. I would expect every competent military has tools to deal with
> satnav these days. (You can buy a jammer off AliBaba for as little as
> $200, spoofing probably costs a lot more.)
>
> It's way harder to spoof the stars.

If you can see them. Warship operations can't be dependent on a lack of fog or
an overcast sky.
Re: What is the oldest computer that could be used today for real work? [message #411334 is a reply to message #411247] Tue, 28 September 2021 09:10 Go to previous messageGo to next message
usenet is currently offline  usenet
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On 25 Sep 2021 04:22:50 -0300, Mike Spencer <mds@bogus.nodomain.nowhere> wrote:
> J. Clarke <jclarke.873638@gmail.com> writes:
>> On 24 Sep 2021 03:10:29 -0300, Mike Spencer
>> <mds@bogus.nodomain.nowhere> wrote:
>>> AIUI, the US Navy now navigates with Windoes, has for many years. And
>>> in addition has dropped astral navigation skills as a requirement for
>>> officers. Furrfu.
>>
>> You do know that a handheld GPS can provide the same information as
>> celestial nav, with vastly greater precision, do you not? And likely
>> has accurate charts these days.
>
> Yes, I do know that. But the US Navy operates *war*ships. If the
> Navy is ever again confronted with an actual war -- something beyond
> sending helicopter gunships or drones after "insurgents" or showing
> the flag in the South China Sea -- against a capable opponent,
> GPS/satnav is going to be the opponent's early target. Naval mariners
> have long had the attitude that they should be prepared to cope when X
> fails for almost all values of X.
>
> I once toured a Canadian naval ship and asked about a hand-crank
> bolted to a bulkhead in a hold near the bilges. The answer: If you
> have a cold ship -- boilers cold, no shore power, nothing operating --
> you unbolt the crank, use it to hand-start an antique single-banger
> diesel. That generates enough power to start the big 8-cyl diesel
> which in turn compresses enough air to start the two really big
> 16-cyl diesels which then generate enough power to fire up and run
> everything else.

Circling back to something on topic: this reminds me of bootstraping
a DEC KI-10. From memory, subject to errors: first you set a code
in a switch register that selects which device to use, for example, paper tape,
then push another button. That loads into memory and executes a small
loader program that reads a bigger bootstrap loader from disk, which in
turn loads and starts the operating system (i.e., the monitor in TOPS-10
parlance).
Re: What is the oldest computer that could be used today for real work? [message #411335 is a reply to message #411278] Tue, 28 September 2021 09:11 Go to previous messageGo to next message
usenet is currently offline  usenet
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On Sat, 25 Sep 2021 22:21:51 +0100, Ahem A Rivet's Shot <steveo@eircom.net>
wrote:
> On Sat, 25 Sep 2021 15:56:30 -0400
> J. Clarke <jclarke.873638@gmail.com> wrote:
>> Why would they not be? There are 100 orbital launches or so a year.
>> It would take that many to knock down all the satnav satellites. And
>> there aren't very many orbital launch facilities in the
>> world--furthermore none of them are hardened.
>
> This and the possibility that there is a separate constellation for
> military use with an authenticated and encrypted protocol and hardened
> satellites. It would be easy enough to do and hide and an elementary common
> sense precaution and it's really hard to steal a private key if the only
> copy is on a satellite.

Easy to do -- perhaps. Easy to hide? No. There are bird watchers, train
spotters, and similarly, people who track satellites. They have the orbital
characteristics for known commercial and military satellites, and watch for
them. So-called "black" satellites tend to stand out because when they are
observed from the ground, their orbits don't match any satellites that people
are claiming credit for.
Re: What is the oldest computer that could be used today for real work? [message #411337 is a reply to message #411294] Tue, 28 September 2021 09:13 Go to previous messageGo to next message
usenet is currently offline  usenet
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On Sun, 26 Sep 2021 12:10:34 -0400, J. Clarke <jclarke.873638@gmail.com> wrote:
> On Sun, 26 Sep 2021 04:24:58 GMT, Charlie Gibbs
> <cgibbs@kltpzyxm.invalid> wrote:
>> On 2021-09-25, Andreas Kohlbach <ank@spamfence.net> wrote:
>>> On Sat, 25 Sep 2021 07:19:54 -0400, J. Clarke wrote:
>>>> On 25 Sep 2021 04:22:50 -0300, Mike Spencer
>>>> <mds@bogus.nodomain.nowhere> wrote:
>>>> >Yes, I do know that. But the US Navy operates *war*ships. If the
>>>> >Navy is ever again confronted with an actual war -- something beyond
>>>> >sending helicopter gunships or drones after "insurgents" or showing
>>>> >the flag in the South China Sea -- against a capable opponent,
>>>> >GPS/satnav is going to be the opponent's early target. Naval mariners
>>>> >have long had the attitude that they should be prepared to cope when X
>>>> >fails for almost all values of X.
>>>>
>>>> Satnav isn't that easy to kill you know. It's not like you can shoot
>>>> one down with a MiG 21. Besides, there are 4 different systems. To
>>>> render satnav unusable would require destroying upwards of 100
>>>> different satellites.
>>>
>>> From what I read there are 31 (US) GPS satellites in orbit. Cannot find
>>> out the distance to one to another. Might be less than 1000
>>> kilometers. If one nuke is fired at a distance of 500 kilometers between
>>> two satellites it might take out both of them. So you (China, or who ever
>>> is the enemy in a future war) need 15 nukes to take out the whole
>>> system. Shouldn't be a problem. Should be even enough to take down only a
>>> few of them to make the system useless.
>>
>> Not really. If you can pick up three satellites you have a 2D position.
>> Four satellites will give you a 3D position. Five will give you RAIM
>> (redundant autonomous integrity monitoring). As long as you have that
>> much of a subset in view, you can still navigate, although perhaps at
>> reduced precision.
>>
>> Occasionally NOTAMs (notices to airmen) are issued warning about possible
>> interruptions to GPS service. They specify a time range when GPS signals
>> may become unreliable within a certain radius of a given spot (smaller
>> radii at low altitudes, larger ones at higher altitudes). The specified
>> location is always at a military base; they're experimenting with jamming
>> the signals.
>
> In addition to what Charlie says:
>
> There are four constellations. We have one, Russia has one, the EU
> has one, and China has one. India is working on one. In a war in
> which the US is involved, we can count on access to at least two of
> those.
>
> Andreas could not find out the distance between the satellites because
> there is no fixed distance. They are in 6 orbital planes with 4 or
> more satellites per plane, at an orbital radius of roughly 16503
> miles. The gory details can be found in
> https://www.gps.gov/technical/ps/2020-SPS-performance-standa rd.pdf.
> You may find
> https://www.faa.gov/about/office_org/headquarters_offices/av s/offices/aam/cami/library/online_libraries/aerospace_medici ne/tutorial/media/iii.4.1.4_describing_orbits.pdf
> helpful in understanding the nomenclature used.
>
> Calculating the actual closest approach is more effort than I want to
> go into for a casual conversation. For a rough estimate of the
> distance between them consider a sphere of radius 16503 miles. That
> has an area of 3,422,438,583 square miles. Divide that by 24 and you
> get 142601607 square miles per satellite. Figure the radius of a
> circle of that area and you get 6737. Double that and you have 13474
> miles. Very very rough estimate, and will vary.

The problem with your calculation is that assumes the satellites are equally
likely to be anywhere around the planet, when in fact by your statement they are
in one of six orbital planes. I don't know what the width of those planes is,
but go ahead and calculate their total area, taking into account where they
overlap. I'll let you simplify the problem by assuming flat bands, instead of
matching the Earth's curvature. I'm sure the total area is much smaller.
Targeting the area where one or more planes intersect may increase
effectiveness.

I don't have any major problem with the rest of your analysis, which leads me to
suggest that a far more practical method to take out the GPS network would be to
launch a payload of small ball bearings into the same orbital plane but going in
the other direction from the satellites. The collateral damage from setting off
a Kessler Syndrome may be very high, but hey, war is hell, right?


> Next, there's the notion of using a nuclear weapon to kill two
> satellites. Let's look at that. Assume the weapon yield is 60
> megatons. The largest nuclear weapon ever demonstrated (Tsar Bomba,
> Soviet test AN602) had a yield of 50-58 megatons depending on whose
> data you believe so that is a reasonable limit. There are no currently
> operational launch systems which could carry a weapon that size to the
> altitude required to attack GPS.
>
> Blast effects. In air the overpressure at 40 miles would be down to 1
> psi. At that overpressure breaking windows is the major effect.
> That's in air--space is a vacuum so the blast effects occur over a
> much smaller radius.
>
> Thermal effects: Beyond 50 miles the thermal intensity is enough to
> produce a sunburn in humans.
>
> Radiation: A Tsar Bomba sized weapon could produce enough radiation
> to damage unshielded rad-hard ICs at up to about 7500 miles. The
> amount of shielding installed on GPS satellites does not appear to be
> available in unclassified documents. At the
>
> EMP:
> This is the one that people always trot out. EMP is an atmospheric
> effect--it is the result of interaction of the nuclear weapon with
> both the magnetic field and the atmosphere and depends on gamma rays
> stripping electrons from atoms in the atmosphere. Its nature is that
> it is directed downward, not upward and there's not enough atmosphere
> at the altitude of GPS satellites to generate an effective E1 or E2
> pulse at their altitude. An E3 pulse could still occur but it
> requires very long transmission lines to have an effect, and that is
> something that satellites do not have.
>
> Intensification of the Van Allen Belt:
> This is something that was demonstrated in several US and Soviet
> nuclear tests. It is not an issue for GPS as they are above the lower
> belt and below the upper one.
>
> Bottom line:
> Trying to take out two satellites with one nuclear weapon is unlikely
> to take out either and would require a Starship/Long March 9/Saturn
> V/N1 class launch vehicle, none of which exist in operational form at
> this time. And if there is to be more than 1 such attempt there will
> have to be hardened silos for such vehicles, which again do not exist
> anywhere at this time--after the first attempt the launch facility
> would become a priority target.
>
> Note also that ICBMs are not designed to attack satellites. They
> could be repurposed to do so but it would require essentially
> reworking them into orbital launchers and their payload would be
> significantly reduced.
Re: What is the oldest computer that could be used today for real work? [message #411338 is a reply to message #411335] Tue, 28 September 2021 09:48 Go to previous messageGo to next message
Ahem A Rivet's Shot is currently offline  Ahem A Rivet's Shot
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On Tue, 28 Sep 2021 13:11:34 GMT
usenet@only.tnx (Questor) wrote:

> On Sat, 25 Sep 2021 22:21:51 +0100, Ahem A Rivet's Shot
> <steveo@eircom.net> wrote:
>> On Sat, 25 Sep 2021 15:56:30 -0400
>> J. Clarke <jclarke.873638@gmail.com> wrote:
>>> Why would they not be? There are 100 orbital launches or so a year.
>>> It would take that many to knock down all the satnav satellites. And
>>> there aren't very many orbital launch facilities in the
>>> world--furthermore none of them are hardened.
>>
>> This and the possibility that there is a separate constellation for
>> military use with an authenticated and encrypted protocol and hardened
>> satellites. It would be easy enough to do and hide and an elementary
>> common sense precaution and it's really hard to steal a private key if
>> the only copy is on a satellite.
>
> Easy to do -- perhaps. Easy to hide? No. There are bird watchers, train
> spotters, and similarly, people who track satellites. They have the

Sure, there are known to be many satellites with undeclared
purpose, who's to say that some of them aren't an encrypted military only
GPS system ?

--
Steve O'Hara-Smith
Odds and Ends at http://www.sohara.org/
Re: What is the oldest computer that could be used today for real work? [message #411343 is a reply to message #411333] Tue, 28 September 2021 15:03 Go to previous messageGo to next message
Charlie Gibbs is currently offline  Charlie Gibbs
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On 2021-09-28, Questor <usenet@only.tnx> wrote:

> On Fri, 24 Sep 2021 20:23:33 -0500, Dave Garland
> <dave.garland@wizinfo.com> wrote:
>
>> On 9/24/2021 5:50 PM, J. Clarke wrote:
>>
>>> You do know that a handheld GPS can provide the same information as
>>> celestial nav, with vastly greater precision, do you not? And likely
>>> has accurate charts these days.
>>
>> Works so long as the satellites are still functioning, not turned
>> off, not jammed, not spoofed. Remember a few years ago Iran fooled
>> a US drone into landing at one of their airfields? Or google "China
>> GPS spoofing" for fun and games with ships near to China. Or the 20
>> ships in the Black Sea in 2017 whose location returned as an airport
>> 32km inland. I would expect every competent military has tools to
>> deal with satnav these days. (You can buy a jammer off AliBaba for
>> as little as $200, spoofing probably costs a lot more.)
>>
>> It's way harder to spoof the stars.
>
> If you can see them. Warship operations can't be dependent on a lack
> of fog or an overcast sky.

True, but it's one more option in your toolkit when conditions permit.
There's an old saying about not putting all your eggs in one basket,
but that seems to have fallen into disfavour these days...

--
/~\ Charlie Gibbs | Life is perverse.
\ / <cgibbs@kltpzyxm.invalid> | It can be beautiful -
X I'm really at ac.dekanfrus | but it won't.
/ \ if you read it the right way. | -- Lily Tomlin
Re: bootstrap, was What is the oldest computer that could be used today for real work? [message #411391 is a reply to message #411334] Wed, 29 September 2021 18:10 Go to previous messageGo to next message
John Levine is currently offline  John Levine
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According to Questor <usenet@only.tnx>:
> Circling back to something on topic: this reminds me of bootstraping
> a DEC KI-10. From memory, subject to errors: first you set a code
> in a switch register that selects which device to use, for example, paper tape,
> then push another button. That loads into memory and executes a small
> loader program that reads a bigger bootstrap loader from disk, which in
> turn loads and starts the operating system (i.e., the monitor in TOPS-10
> parlance).

Sounds like S/360. You set the device number of the IPL (initial program load)
device in the switches and pressed the IPL button. That ran a fixed one instruction
channel program pretending to be at location 0, that read 24 bytes into 0-23, then
executed whatever was read into locaion 8, typically another read command to read
a disk or tape block with real bootstrap, then started the computer by restoring the status word at
location 0 which runs the bootstrap just read in to start up the computer.






--
Regards,
John Levine, johnl@taugh.com, Primary Perpetrator of "The Internet for Dummies",
Please consider the environment before reading this e-mail. https://jl.ly
Re: bootstrap, was What is the oldest computer that could be used today for real work? [message #411396 is a reply to message #411391] Wed, 29 September 2021 23:16 Go to previous messageGo to next message
Anne &amp; Lynn Wheel is currently offline  Anne &amp; Lynn Wheel
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John Levine <johnl@taugh.com> writes:
> Sounds like S/360. You set the device number of the IPL (initial
> program load) device in the switches and pressed the IPL button. That
> ran a fixed one instruction channel program pretending to be at
> location 0, that read 24 bytes into 0-23, then executed whatever was
> read into locaion 8, typically another read command to read a disk or
> tape block with real bootstrap, then started the computer by restoring
> the status word at location 0 which runs the bootstrap just read in to
> start up the computer.

old post to ibm-main & alt.folklore.computers
http://www.garlic.com/~lynn/2007f.html#1
discussing 360 "3card loader" and BPS (card) loader ... also
references "How to cread CDROM IPL Images" for use with hercules
(mainframe emulator)
https://www.cbttape.org/~jjaeger/cdrom.html

following is from old assemble program ... it can bootstrap load the
assembler program it is included in ... the "xxx"s originally were
EBCDIC HEX

************************************************************ *********** 00046000
* * 00047000
* TWO-CARD ABSOLUTE LOADER -- THE FOLLOWING ARE SELF-LOADING * 00048000
* IPL-ABLE CARDS THAT LOAD A CHANNEL PROGRAM WHICH FUNCTIONS * 00049000
* AS AN ABSOLUTE TXT CARD LOADER, EXECUTING AS A COMMAND CHAIN * 00050000
* FROM THE INITIAL IPL READ. IF PUNCHED BEFORE ANY ASSEMBLED * 00051000
* INSTRUCTIONS OR DATA, THE TEXT FILE THE ASSEMBLER PRODUCES * 00052000
* MAY BE CONVERTED INTO A SELF-LOADING DECK BY USING AN EDITOR * 00053000
* TO DELETE ANY RECORDS PRECEDING THE TWO LOADER CARDS, WHICH * 00054000
* IMMEDIATELY PRECEDE THE FIRST TXT RECORD IN THE TEXT OUTPUT. * 00055000
* * 00056000
* NO CONSTANTS MAY BE ASSEMBLED IN THE ABSOLUTE ADDRESS RANGE * 00057000
* X'10' TO X'43', AS THEIR LOADING WOULD OVERWRITE THE LOADER * 00058000
* AND CAUSE IPL FAILURES. THE LOADER OPERATION IS TERMINATED * 00059000
* BY LOADING AN ORDINARY NOP CCW AT LOCATION X'40'. WHEN THE * 00060000
* ASSEMBLY BEGINS WITH A 'LABEL START 0' STATEMENT, THIS COULD * 00061000
* BE ACCOMPLISHED BY INSERTING THE SEQUENCE: * 00062000
* * 00063000
* ORG LABEL+X'40' * 00064000
* CCW X'03',0,X'20',1 * 00065000
* * 00066000
* FOLLOWING THE FINAL STATEMENT SPECIFYING ASSEMBLED OUTPUT TO * 00067000
* BE LOADED. * 00068000
* * 00069000
* * 00071000
PUNCH 'xxxxxxxxxxxxxxxxxxxxxxxxFIRST LOADABLE RECORD' CARD 1 * 00072000
PUNCH 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx' CARD 2 * 00073000
* * 00074000
************************************************************ *********** 00075000

recent post (to facebook) about early CP67, including discussion of
(assemble output) BPS "TXT" deck loading
http://www.garlic.com/~lynn/2021i.html#61


--
virtualization experience starting Jan1968, online at home since Mar1970
Re: What is the oldest computer that could be used today for real work? [message #411409 is a reply to message #410756] Thu, 30 September 2021 09:34 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: 711 Spooky Mart

On 9/6/21 1:30 AM, Jason Evans wrote:
> On Mon, 06 Sep 2021 00:06:43 -0400, J. Clarke wrote:
>
>> You can run Unix from a teletype. Not something anyone in their right
>> mind wants to do these days but you can do it.
>
> Linux via ham radio RTTY would be stupid and awesome, lol.
>

I've been poking around for packet radio equipment. I want to automate
backups of some critical data files to a solar-powered rig located
several miles from my home office without requiring Internet to do it. A
very simple CLI debian netinstall would probably get the job done.

Any decent, modern packet radio requires a more modern computer board.
Anything legacy is going to be really slow and potentially unreliable.

I've even thought about a LIDAR setup, although those are quite pricey
right now.

--
████████████████████ ███████████████
█░░░░░░░░░░░█░░░░░░░ ░███░░░░░░░░███
█░░███████░░█░░████░ ░███░░████░░███ [chan] 711
█░░░░░░░██░░█░░░░██░ ░███░░░░██░░███ spooky mart
██████░░██░░███░░██░ ░█████░░██░░███ always open
██████░░██░░███░░██░ ░█████░░██░░███ stay spooky
██████░░██░░█░░░░██░ ░░░█░░░░██░░░░█ https://bitmessage.org
██████░░██░░█░░█████ █░░█░░██████░░█
██████░░░░░░█░░░░░░░ ░░░█░░░░░░░░░░█
████████████████████ ███████████████
Re: bootstrap, was What is the oldest computer that could be used today for real work? [message #411410 is a reply to message #411391] Thu, 30 September 2021 10:29 Go to previous messageGo to next message
scott is currently offline  scott
Messages: 3946
Registered: February 2012
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Senior Member
John Levine <johnl@taugh.com> writes:
> According to Questor <usenet@only.tnx>:
>> Circling back to something on topic: this reminds me of bootstraping
>> a DEC KI-10. From memory, subject to errors: first you set a code
>> in a switch register that selects which device to use, for example, paper tape,
>> then push another button. That loads into memory and executes a small
>> loader program that reads a bigger bootstrap loader from disk, which in
>> turn loads and starts the operating system (i.e., the monitor in TOPS-10
>> parlance).
>
> Sounds like S/360. You set the device number of the IPL (initial program load)
> device in the switches and pressed the IPL button. That ran a fixed one instruction
> channel program pretending to be at location 0, that read 24 bytes into 0-23, then
> executed whatever was read into locaion 8, typically another read command to read
> a disk or tape block with real bootstrap, then started the computer by restoring the status word at
> location 0 which runs the bootstrap just read in to start up the computer.

The Burroughs B3500 coldstart process was similar. The operator would
enter an Initiate I/O (IIO) instruction at address zero and execute it[*];
it would read in the first card and transfer control to data read from
the card, which would read in subsequent cards to complete the bootstrap
program, which would then read in the MCP from tape (or disk (100byte sectors)
or pack (180 byte sectors)) to memory and transfer control to the MCP.

The MCP would complete the coldstart process by initializing the disk
data structures (directory, free list, disk bootstrap sector, etc),
reading in the configuration file (from cards) and completing the coldstart process.

[*] The FE would strap the disk bootstrap channel in the processor so the
halt/load (bootstrap) button would read the first sector of a disk on that
channel and transfer control to it when booting subsequent to the coldstart.
Re: bootstrap, was What is the oldest computer that could be used today for real work? [message #411412 is a reply to message #411391] Thu, 30 September 2021 10:41 Go to previous messageGo to next message
Charles Richmond is currently offline  Charles Richmond
Messages: 2667
Registered: December 2011
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Senior Member
On 9/29/2021 5:10 PM, John Levine wrote:
> According to Questor <usenet@only.tnx>:
>> Circling back to something on topic: this reminds me of bootstraping
>> a DEC KI-10. From memory, subject to errors: first you set a code
>> in a switch register that selects which device to use, for example, paper tape,
>> then push another button. That loads into memory and executes a small
>> loader program that reads a bigger bootstrap loader from disk, which in
>> turn loads and starts the operating system (i.e., the monitor in TOPS-10
>> parlance).
>
> Sounds like S/360. You set the device number of the IPL (initial program load)
> device in the switches and pressed the IPL button. That ran a fixed one instruction
> channel program pretending to be at location 0, that read 24 bytes into 0-23, then
> executed whatever was read into locaion 8, typically another read command to read
> a disk or tape block with real bootstrap, then started the computer by restoring the status word at
> location 0 which runs the bootstrap just read in to start up the computer.
>

If it's like the IBM IPL I know... sit down and be prepared to wait
a-while. Where I went to uni, the IBM 370/155 took about 20 minutes to
IPL. Something about "waiting for the time-base generator to come up to
speed" I think... Power supply voltage levels were involved, and
sequencing the power-on of equipment to prevent power surges.

'course that's been a *long* time ago for me!!!


--

Charles Richmond


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Re: What is the oldest computer that could be used today for real work? [message #411413 is a reply to message #411343] Thu, 30 September 2021 10:46 Go to previous messageGo to next message
Charles Richmond is currently offline  Charles Richmond
Messages: 2667
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Senior Member
On 9/28/2021 2:03 PM, Charlie Gibbs wrote:
> On 2021-09-28, Questor <usenet@only.tnx> wrote:
>
>> On Fri, 24 Sep 2021 20:23:33 -0500, Dave Garland
>> <dave.garland@wizinfo.com> wrote:
>>
>>> On 9/24/2021 5:50 PM, J. Clarke wrote:
>>>
>>>> You do know that a handheld GPS can provide the same information as
>>>> celestial nav, with vastly greater precision, do you not? And likely
>>>> has accurate charts these days.
>>>
>>> Works so long as the satellites are still functioning, not turned
>>> off, not jammed, not spoofed. Remember a few years ago Iran fooled
>>> a US drone into landing at one of their airfields? Or google "China
>>> GPS spoofing" for fun and games with ships near to China. Or the 20
>>> ships in the Black Sea in 2017 whose location returned as an airport
>>> 32km inland. I would expect every competent military has tools to
>>> deal with satnav these days. (You can buy a jammer off AliBaba for
>>> as little as $200, spoofing probably costs a lot more.)
>>>
>>> It's way harder to spoof the stars.
>>
>> If you can see them. Warship operations can't be dependent on a lack
>> of fog or an overcast sky.
>
> True, but it's one more option in your toolkit when conditions permit.
> There's an old saying about not putting all your eggs in one basket,
> but that seems to have fallen into disfavour these days...
>

All true! Now-a-days the one basket for "all your eggs" is called the
smart cell phone. Now when a person loses their smart cell phone, that
person is put back to counting rocks at the opening of the cave where
they live. ;-)

--

Charles Richmond

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Re: bootstrap, was What is the oldest computer that could be used today for real work? [message #411414 is a reply to message #411412] Thu, 30 September 2021 11:03 Go to previous messageGo to next message
Dan Espen is currently offline  Dan Espen
Messages: 3749
Registered: January 2012
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Senior Member
Charles Richmond <codescott@aquaporin4.com> writes:

> On 9/29/2021 5:10 PM, John Levine wrote:
>> According to Questor <usenet@only.tnx>:
>>> Circling back to something on topic: this reminds me of bootstraping
>>> a DEC KI-10. From memory, subject to errors: first you set a code
>>> in a switch register that selects which device to use, for example, paper tape,
>>> then push another button. That loads into memory and executes a small
>>> loader program that reads a bigger bootstrap loader from disk, which in
>>> turn loads and starts the operating system (i.e., the monitor in TOPS-10
>>> parlance).
>> Sounds like S/360. You set the device number of the IPL (initial
>> program load)
>> device in the switches and pressed the IPL button. That ran a fixed one instruction
>> channel program pretending to be at location 0, that read 24 bytes into 0-23, then
>> executed whatever was read into locaion 8, typically another read command to read
>> a disk or tape block with real bootstrap, then started the computer by restoring the status word at
>> location 0 which runs the bootstrap just read in to start up the computer.
>>
>
> If it's like the IBM IPL I know... sit down and be prepared to wait
> a-while. Where I went to uni, the IBM 370/155 took about 20 minutes
> to IPL. Something about "waiting for the time-base generator to come
> up to speed" I think... Power supply voltage levels were involved,
> and sequencing the power-on of equipment to prevent power surges.
>
> 'course that's been a *long* time ago for me!!!

I think that was characteristic of OS/VS.

DOS and DOS/VS managed a minute or 2.

The IBM 1401 booted just about the same as the other machines mentioned.
Clear 1-80, read a card into 1-80, branch to 1.

Unlike the S/360, I don't remember any way to make a 1401 boot from
other media.

--
Dan Espen
Re: What is the oldest computer that could be used today for real work? [message #411420 is a reply to message #411413] Thu, 30 September 2021 13:44 Go to previous messageGo to next message
Charlie Gibbs is currently offline  Charlie Gibbs
Messages: 5048
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Senior Member
On 2021-09-30, Charles Richmond <codescott@aquaporin4.com> wrote:

> On 9/28/2021 2:03 PM, Charlie Gibbs wrote:
>
>> On 2021-09-28, Questor <usenet@only.tnx> wrote:
>>
>>> On Fri, 24 Sep 2021 20:23:33 -0500, Dave Garland
>>> <dave.garland@wizinfo.com> wrote:
>>>
>>>> On 9/24/2021 5:50 PM, J. Clarke wrote:
>>>>
>>>> > You do know that a handheld GPS can provide the same information as
>>>> > celestial nav, with vastly greater precision, do you not? And likely
>>>> > has accurate charts these days.
>>>>
>>>> Works so long as the satellites are still functioning, not turned
>>>> off, not jammed, not spoofed. Remember a few years ago Iran fooled
>>>> a US drone into landing at one of their airfields? Or google "China
>>>> GPS spoofing" for fun and games with ships near to China. Or the 20
>>>> ships in the Black Sea in 2017 whose location returned as an airport
>>>> 32km inland. I would expect every competent military has tools to
>>>> deal with satnav these days. (You can buy a jammer off AliBaba for
>>>> as little as $200, spoofing probably costs a lot more.)
>>>>
>>>> It's way harder to spoof the stars.
>>>
>>> If you can see them. Warship operations can't be dependent on a lack
>>> of fog or an overcast sky.
>>
>> True, but it's one more option in your toolkit when conditions permit.
>> There's an old saying about not putting all your eggs in one basket,
>> but that seems to have fallen into disfavour these days...
>
> All true! Now-a-days the one basket for "all your eggs" is called the
> smart cell phone. Now when a person loses their smart cell phone, that
> person is put back to counting rocks at the opening of the cave where
> they live. ;-)

Yup. The other example of one basket for all your eggs is the Cloud.
And it's not even your own basket.

"All your data are belong to us."

--
/~\ Charlie Gibbs | Life is perverse.
\ / <cgibbs@kltpzyxm.invalid> | It can be beautiful -
X I'm really at ac.dekanfrus | but it won't.
/ \ if you read it the right way. | -- Lily Tomlin
Re: What is the oldest computer that could be used today for real work? [message #411422 is a reply to message #411420] Thu, 30 September 2021 14:10 Go to previous messageGo to next message
Ahem A Rivet's Shot is currently offline  Ahem A Rivet's Shot
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On Thu, 30 Sep 2021 17:44:06 GMT
Charlie Gibbs <cgibbs@kltpzyxm.invalid> wrote:

> On 2021-09-30, Charles Richmond <codescott@aquaporin4.com> wrote:
>
>> All true! Now-a-days the one basket for "all your eggs" is called the
>> smart cell phone. Now when a person loses their smart cell phone, that
>> person is put back to counting rocks at the opening of the cave where
>> they live. ;-)

Nah it's fine they have it all backed up in the cloud, they just
get a new one and the nice man at the shop helps them to get it all back.

> Yup. The other example of one basket for all your eggs is the Cloud.
> And it's not even your own basket.

Yes well there is that. However you can do what I do and run your
own 'cloud services' and then persuade the phone to use them instead of the
default ones. Not that there's much on the phone outside of the contact
list which rather has to be there.

> "All your data are belong to us."

Keep your data close.

--
Steve O'Hara-Smith
Odds and Ends at http://www.sohara.org/
Re: bootstrap, was What is the oldest computer that could be used today for real work? [message #411426 is a reply to message #411414] Thu, 30 September 2021 15:16 Go to previous messageGo to next message
Anne &amp; Lynn Wheel is currently offline  Anne &amp; Lynn Wheel
Messages: 3081
Registered: January 2012
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Senior Member
Dan Espen <dan1espen@gmail.com> writes:
> I think that was characteristic of OS/VS.
>
> DOS and DOS/VS managed a minute or 2.
>
> The IBM 1401 booted just about the same as the other machines mentioned.
> Clear 1-80, read a card into 1-80, branch to 1.
>
> Unlike the S/360, I don't remember any way to make a 1401 boot from
> other media.

CP/67 and VM/370 came up in several seconds. Early on CP/67 (that
carried over to VM/370) for being up 7/24 dark room with no operator.
There was even special handling for system crash, automatically take
dump core image ... and automagically re-ipl and be back up and running.

Also back to days when all IBM mainframes were rented and charges based
on "system meter" reading that ran whenever the CPU and/or any channel
was running ... CP/67 developed special channel programs that let
channel go idle but would immediately wake-up for any characters
arriving on a line ... to reduce offshift, light load costs
(and help encourage leaving system up and available 7x24, also
goes for running w/o an operator/human present).

All activity had to be idle for 400ms before "system meter" would
actually stop running. Note: long after IBM had switched mainframes from
lease/rent to sales ... MVS (VS/2) still had a timer task that woke up
every 400ms (to guarantee that system meter never stopped)


--
virtualization experience starting Jan1968, online at home since Mar1970
Re: bootstrap, was What is the oldest computer that could be used today for real work? [message #411436 is a reply to message #411410] Thu, 30 September 2021 20:43 Go to previous messageGo to next message
Peter Flass is currently offline  Peter Flass
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Scott Lurndal <scott@slp53.sl.home> wrote:
> John Levine <johnl@taugh.com> writes:
>> According to Questor <usenet@only.tnx>:
>>> Circling back to something on topic: this reminds me of bootstraping
>>> a DEC KI-10. From memory, subject to errors: first you set a code
>>> in a switch register that selects which device to use, for example, paper tape,
>>> then push another button. That loads into memory and executes a small
>>> loader program that reads a bigger bootstrap loader from disk, which in
>>> turn loads and starts the operating system (i.e., the monitor in TOPS-10
>>> parlance).
>>
>> Sounds like S/360. You set the device number of the IPL (initial program load)
>> device in the switches and pressed the IPL button. That ran a fixed one instruction
>> channel program pretending to be at location 0, that read 24 bytes into 0-23, then
>> executed whatever was read into locaion 8, typically another read command to read
>> a disk or tape block with real bootstrap, then started the computer by
>> restoring the status word at
>> location 0 which runs the bootstrap just read in to start up the computer.
>
> The Burroughs B3500 coldstart process was similar. The operator would
> enter an Initiate I/O (IIO) instruction at address zero and execute it[*];
> it would read in the first card and transfer control to data read from
> the card, which would read in subsequent cards to complete the bootstrap
> program, which would then read in the MCP from tape (or disk (100byte sectors)
> or pack (180 byte sectors)) to memory and transfer control to the MCP.
>
> The MCP would complete the coldstart process by initializing the disk
> data structures (directory, free list, disk bootstrap sector, etc),
> reading in the configuration file (from cards) and completing the coldstart process.
>
> [*] The FE would strap the disk bootstrap channel in the processor so the
> halt/load (bootstrap) button would read the first sector of a disk on that
> channel and transfer control to it when booting subsequent to the coldstart.
>
we
On the CDC6400, the operator had to toggle in a small “dead start” program
on the console to boot the system.

--
Pete
Re: bootstrap, was What is the oldest computer that could be used today for real work? [message #411437 is a reply to message #411414] Thu, 30 September 2021 20:43 Go to previous messageGo to next message
Peter Flass is currently offline  Peter Flass
Messages: 7973
Registered: December 2011
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Dan Espen <dan1espen@gmail.com> wrote:
> Charles Richmond <codescott@aquaporin4.com> writes:
>
>> On 9/29/2021 5:10 PM, John Levine wrote:
>>> According to Questor <usenet@only.tnx>:
>>>> Circling back to something on topic: this reminds me of bootstraping
>>>> a DEC KI-10. From memory, subject to errors: first you set a code
>>>> in a switch register that selects which device to use, for example, paper tape,
>>>> then push another button. That loads into memory and executes a small
>>>> loader program that reads a bigger bootstrap loader from disk, which in
>>>> turn loads and starts the operating system (i.e., the monitor in TOPS-10
>>>> parlance).
>>> Sounds like S/360. You set the device number of the IPL (initial
>>> program load)
>>> device in the switches and pressed the IPL button. That ran a fixed one instruction
>>> channel program pretending to be at location 0, that read 24 bytes into 0-23, then
>>> executed whatever was read into locaion 8, typically another read command to read
>>> a disk or tape block with real bootstrap, then started the computer by
>>> restoring the status word at
>>> location 0 which runs the bootstrap just read in to start up the computer.
>>>
>>
>> If it's like the IBM IPL I know... sit down and be prepared to wait
>> a-while. Where I went to uni, the IBM 370/155 took about 20 minutes
>> to IPL. Something about "waiting for the time-base generator to come
>> up to speed" I think... Power supply voltage levels were involved,
>> and sequencing the power-on of equipment to prevent power surges.
>>
>> 'course that's been a *long* time ago for me!!!
>
> I think that was characteristic of OS/VS.
>
> DOS and DOS/VS managed a minute or 2.
>
> The IBM 1401 booted just about the same as the other machines mentioned.
> Clear 1-80, read a card into 1-80, branch to 1.
>
> Unlike the S/360, I don't remember any way to make a 1401 boot from
> other media.
>

I believe I just read that the IBM 1130 had to be booted from the card
reader. Of china course, since it had core memory it could be powered down
and up without having to to reboot, so I’m not sure I ever experienced
this.

--
Pete
Re: bootstrap, was What is the oldest computer that could be used today for real work? [message #411444 is a reply to message #411437] Fri, 01 October 2021 01:18 Go to previous messageGo to next message
Ahem A Rivet's Shot is currently offline  Ahem A Rivet's Shot
Messages: 4471
Registered: January 2012
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Senior Member
On Thu, 30 Sep 2021 17:43:23 -0700
Peter Flass <peter_flass@yahoo.com> wrote:

> I believe I just read that the IBM 1130 had to be booted from the card
> reader.

That is correct, the card was punched with a binary that could load
the real boot code from disk. I used it fairly often, the 1130 was an easy
machine for students to crash.

--
Steve O'Hara-Smith
Odds and Ends at http://www.sohara.org/
Re: What is the oldest computer that could be used today for real work? [message #411449 is a reply to message #411153] Fri, 01 October 2021 06:48 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: Vir Campestris

On 23/09/2021 02:15, Dan Espen wrote:
> You only update software when the benefit justifies the cost.

The problem is that a lot of updates don't add any real functionality,
they just plug security holes that someone has found.

Andy
Re: What is the oldest computer that could be used today for real work? [message #411450 is a reply to message #410715] Fri, 01 October 2021 07:38 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: vladimir...@gmail.com

A real life example. My father-in-law is a math professor of some notoriety, he had his own wiki page for a while. He is semi-retired and works from home. I was surprised to see that his system is a P-100 running Windows 95. He uses LATEX, a pascal compiler and Outlook email client. SO he completely refused to talk about upgrading because his current system does everything he needs.
Re: What is the oldest computer that could be used today for real work? [message #411458 is a reply to message #411449] Fri, 01 October 2021 13:43 Go to previous messageGo to next message
Charlie Gibbs is currently offline  Charlie Gibbs
Messages: 5048
Registered: January 2012
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Senior Member
On 2021-10-01, Vir Campestris <vir.campestris@invalid.invalid> wrote:

> On 23/09/2021 02:15, Dan Espen wrote:
>
>> You only update software when the benefit justifies the cost.
>
> The problem is that a lot of updates don't add any real functionality,
> they just plug security holes that someone has found.

Or they add security holes when the vendors decide they don't
don't have their hooks into you deeply enough.

--
/~\ Charlie Gibbs |
\ / <cgibbs@kltpzyxm.invalid> | "Alexa, define 'bugging'."
X I'm really at ac.dekanfrus |
/ \ if you read it the right way. |
Re: What is the oldest computer that could be used today for real work? [message #411459 is a reply to message #411450] Fri, 01 October 2021 13:43 Go to previous messageGo to next message
Charlie Gibbs is currently offline  Charlie Gibbs
Messages: 5048
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Senior Member
On 2021-10-01, vladimir...@gmail.com <vladimir.rodionov@gmail.com>
wrote:

> A real life example. My father-in-law is a math professor of some
> notoriety, he had his own wiki page for a while. He is semi-retired
> and works from home. I was surprised to see that his system is a P-100
> running Windows 95. He uses LATEX, a pascal compiler and Outlook email
> client. SO he completely refused to talk about upgrading because his
> current system does everything he needs.

I love to mess with salesmen's minds by gushing over how much
I love something that they sold me a few years ago, crushing
their hopes of selling me a newer model. Jeff Bezos can take
his "divine discontent" and shove it wherever his ingenuity
may devise and complacency permit.

--
/~\ Charlie Gibbs | Life is perverse.
\ / <cgibbs@kltpzyxm.invalid> | It can be beautiful -
X I'm really at ac.dekanfrus | but it won't.
/ \ if you read it the right way. | -- Lily Tomlin
Re: bootstrap, was What is the oldest computer that could be used today for real work? [message #411484 is a reply to message #411436] Fri, 01 October 2021 23:04 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: drb

> On the CDC6400, the operator had to toggle in a small “dead start” program
> on the console to boot the system.

Actually, a switch panel stashed in one of the cabinets held 17B PP
words worth of deadstart program. It was rarely fiddled with.

De
Re: What is the oldest computer that could be used today for real work? [message #411554 is a reply to message #411450] Sun, 03 October 2021 15:14 Go to previous messageGo to next message
Peter Flass is currently offline  Peter Flass
Messages: 7973
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vladimir...@gmail.com <vladimir.rodionov@gmail.com> wrote:
> A real life example. My father-in-law is a math professor of some
> notoriety, he had his own wiki page for a while. He is semi-retired and
> works from home. I was surprised to see that his system is a P-100
> running Windows 95. He uses LATEX, a pascal compiler and Outlook email
> client. SO he completely refused to talk about upgrading because his
> current system does everything he needs.
>

Makes sense. Every time you “upgrade” you have to waste a lot of time
re-doing the customizations from your old system that make it so easy to
use. You also have to learn new”muscle memory” things like key combinations
(ctrl-alt-del for example). Your old software may not work, and new
versions may not work the same. It’s a lot of work just to get back to
where you were before.

--
Pete
Re: What is the oldest computer that could be used today for real work? [message #411555 is a reply to message #411458] Sun, 03 October 2021 16:43 Go to previous messageGo to previous message
Anonymous
Karma:
Originally posted by: Vir Campestris

On 01/10/2021 18:43, Charlie Gibbs wrote:
> On 2021-10-01, Vir Campestris <vir.campestris@invalid.invalid> wrote:
>
>> On 23/09/2021 02:15, Dan Espen wrote:
>>
>>> You only update software when the benefit justifies the cost.
>>
>> The problem is that a lot of updates don't add any real functionality,
>> they just plug security holes that someone has found.
>
> Or they add security holes when the vendors decide they don't
> don't have their hooks into you deeply enough.
>

I'm paranoid, but I'm not _that_ paranoid.

Do you have a source for that assertion?

Andy
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