In any case it's become very clear that a major update is needed for
the US airport/routing system. Knowing the govt process, the stuff
will already be obsolete by the time it's installed, but not nearly
SO obsolete.
There are few radiation-hardened chips coming out these days. We're
still talking 80s tech. Slow - but robust. Big enough transistors so
cosmic rays and such won't compromise things.
On Fri, 13 Jun 2025 22:38:38 -0400, c186282 wrote:
In any case it's become very clear that a major update is needed for
the US airport/routing system. Knowing the govt process, the stuff
will already be obsolete by the time it's installed, but not nearly
SO obsolete.
In the early '70s we had a contract to build the controllers for the ALS system. The heart of the controller was an Eagle Signal electromechanical stepping switch which was pretty much obsolete. The harnesses had to be
laced since the FAA wasn't sure about those new-fangled nylon cable ties.
There are few radiation-hardened chips coming out these days. We're
still talking 80s tech. Slow - but robust. Big enough transistors so
cosmic rays and such won't compromise things.
One project I worked on used TI's TMS9900 microprocessor of TI-99/4 fame.
Or notoriety, take your pick. Its claim to fame was TI produced rad-hard parts. TI had ties to the defense industry that made them a natural.
TI was also involved with the 'expert systems' flavor of AI after neural networks fell on their face in the '80s.
On 6/13/25 11:35 PM, rbowman wrote:
On Fri, 13 Jun 2025 22:38:38 -0400, c186282 wrote:
In any case it's become very clear that a major update is needed for >>> the US airport/routing system. Knowing the govt process, the stuff
will already be obsolete by the time it's installed, but not nearly
SO obsolete.
In the early '70s we had a contract to build the controllers for the ALS
system. The heart of the controller was an Eagle Signal electromechanical
stepping switch which was pretty much obsolete. The harnesses had to be
laced since the FAA wasn't sure about those new-fangled nylon cable ties.
Ooooh ! Nylon ! EVIL !!! :-)
But yes, it's VERY typical for govt projects to be
WAY behind the tech curve. The specs are writ, but
then there's a HUGE delay in the implementation.
The lunar-lander computer still used "rope memory"
because of that - even though PROMS and erasable
PROMS were widely available by the late 60s.
Took a tour of an attack sub in the late 80s - a bud
of mine was crew so I got the better tour. Ever put
your hand on a torpedo ? The sonar 'room' was highest
tech ... but that tech involved a cubic-meter CPU box
with a few of the old removable-stack hard drives ...
early 70s/late-60s tech. Same reasons as mentioned -
the vast delay between conception and realization.
The sonar guy seemed well versed in making best USE
of that equipment, but STILL !!!
Some of this is why I'd like people like Musk in the
loop - chop years, maybe a decade, out of that awful
process. It's NOT good to be too far behind the curve.
There are few radiation-hardened chips coming out these days. We're
still talking 80s tech. Slow - but robust. Big enough transistors so >>> cosmic rays and such won't compromise things.
One project I worked on used TI's TMS9900 microprocessor of TI-99/4 fame.
Or notoriety, take your pick. Its claim to fame was TI produced rad-hard
parts. TI had ties to the defense industry that made them a natural.
c186282 <c186282@nnada.net> wrote:
On 6/13/25 11:35 PM, rbowman wrote:
On Fri, 13 Jun 2025 22:38:38 -0400, c186282 wrote:Ooooh ! Nylon ! EVIL !!! :-)
In any case it's become very clear that a major update is needed for >>>> the US airport/routing system. Knowing the govt process, the stuff >>>> will already be obsolete by the time it's installed, but not nearly >>>> SO obsolete.
In the early '70s we had a contract to build the controllers for the ALS >>> system. The heart of the controller was an Eagle Signal electromechanical >>> stepping switch which was pretty much obsolete. The harnesses had to be
laced since the FAA wasn't sure about those new-fangled nylon cable ties. >>
Not so much that as: Ooooh!, we don't know how well this new "tie"
method will withstand extremes of cold, hot and vibration, and the
current regs. specify "laced" and we *do* know how lacing withstands extremes of cold, hot and vibration.
But yes, it's VERY typical for govt projects to be
WAY behind the tech curve. The specs are writ, but
then there's a HUGE delay in the implementation.
The lunar-lander computer still used "rope memory"
because of that - even though PROMS and erasable
PROMS were widely available by the late 60s.
Also because (esp. for EPROMS) the rope memory was much more radiation hardened than EPROMS of the day were. Also, for 'long duration'
projects such as that, often each component is designed and built, then
in the end the various parts are pieced together to produce the "flying candle" you see on launch. But the "computer" might have been designed
and built five years before that launch, and minus five years from
today might have meant no PROM or EPROMS were even available at the
time.
For electronics that have to go into space, radiation hardened is a
must. Send your phone into space and in very short order all kinds of weirdness and corruption will occur.
c186282 <c186282@nnada.net> wrote:
On 6/13/25 11:35 PM, rbowman wrote:
On Fri, 13 Jun 2025 22:38:38 -0400, c186282 wrote:Ooooh ! Nylon ! EVIL !!! :-)
In any case it's become very clear that a major update is needed for >>>> the US airport/routing system. Knowing the govt process, the stuff >>>> will already be obsolete by the time it's installed, but not nearly >>>> SO obsolete.
In the early '70s we had a contract to build the controllers for the ALS >>> system. The heart of the controller was an Eagle Signal electromechanical >>> stepping switch which was pretty much obsolete. The harnesses had to be
laced since the FAA wasn't sure about those new-fangled nylon cable ties. >>
Not so much that as: Ooooh!, we don't know how well this new "tie"
method will withstand extremes of cold, hot and vibration, and the
current regs. specify "laced" and we *do* know how lacing withstands extremes of cold, hot and vibration.
But yes, it's VERY typical for govt projects to be
WAY behind the tech curve. The specs are writ, but
then there's a HUGE delay in the implementation.
The lunar-lander computer still used "rope memory"
because of that - even though PROMS and erasable
PROMS were widely available by the late 60s.
Also because (esp. for EPROMS) the rope memory was much more radiation hardened than EPROMS of the day were. Also, for 'long duration'
projects such as that, often each component is designed and built, then
in the end the various parts are pieced together to produce the "flying candle" you see on launch. But the "computer" might have been designed
and built five years before that launch, and minus five years from
today might have meant no PROM or EPROMS were even available at the
time.
Took a tour of an attack sub in the late 80s - a bud
of mine was crew so I got the better tour. Ever put
your hand on a torpedo ? The sonar 'room' was highest
tech ... but that tech involved a cubic-meter CPU box
with a few of the old removable-stack hard drives ...
early 70s/late-60s tech. Same reasons as mentioned -
the vast delay between conception and realization.
Yep, the entire sub likely took 10+ years to design and build. By the
time the submariners get to launch their "new" sub, most of the tech on
board would look dated (by the standards of the commercial world)
because it was designed minus ten or minus fifteen years ago, with
posssiby cutting edge tech then, but no longer cutting edge "today".
Few commercial products see more than a couple years of total sales
before they get a "redesign", none of them have been undergoing design
and build for fifteen years when they hit the market.
The sonar guy seemed well versed in making best USE
of that equipment, but STILL !!!
Some of this is why I'd like people like Musk in the
loop - chop years, maybe a decade, out of that awful
process. It's NOT good to be too far behind the curve.
Musk isn't the savior here. His method (fire everyone then oops..
hire back some we really needed) won't work for projects that do really
need years to design and build (because they are largely "one-offs" --
i.e., Navy might have built 10 or 20 subs, Apple builds a million plus iphones a week). For something like a sub, you simply won't build one
in six months to a year like for a phone (well, not unless you want it
to implode at depth like that carbon fiber one did a couple years ago).
There are few radiation-hardened chips coming out these days. We're >>>> still talking 80s tech. Slow - but robust. Big enough transistors so >>>> cosmic rays and such won't compromise things.
One project I worked on used TI's TMS9900 microprocessor of TI-99/4 fame. >>> Or notoriety, take your pick. Its claim to fame was TI produced rad-hard >>> parts. TI had ties to the defense industry that made them a natural.
For electronics that have to go into space, radiation hardened is a
must. Send your phone into space and in very short order all kinds of weirdness and corruption will occur.
On 14/06/2025 17:34, Rich wrote:
c186282 <c186282@nnada.net> wrote:There is another issue I ran into. On an undersea cable repeater. IN
On 6/13/25 11:35 PM, rbowman wrote:
On Fri, 13 Jun 2025 22:38:38 -0400, c186282 wrote:
In any case it's become very clear that a major update is
needed for
the US airport/routing system. Knowing the govt process, the >>>>> stuff
will already be obsolete by the time it's installed, but not >>>>> nearly
SO obsolete.
In the early '70s we had a contract to build the controllers for the
ALS
system. The heart of the controller was an Eagle Signal
electromechanical
stepping switch which was pretty much obsolete. The harnesses had to be >>>> laced since the FAA wasn't sure about those new-fangled nylon cable
ties.
Ooooh ! Nylon ! EVIL !!! :-)
Not so much that as: Ooooh!, we don't know how well this new "tie"
method will withstand extremes of cold, hot and vibration, and the
current regs. specify "laced" and we *do* know how lacing withstands
extremes of cold, hot and vibration.
But yes, it's VERY typical for govt projects to be
WAY behind the tech curve. The specs are writ, but
then there's a HUGE delay in the implementation.
The lunar-lander computer still used "rope memory"
because of that - even though PROMS and erasable
PROMS were widely available by the late 60s.
Also because (esp. for EPROMS) the rope memory was much more radiation
hardened than EPROMS of the day were. Also, for 'long duration'
projects such as that, often each component is designed and built, then
in the end the various parts are pieced together to produce the "flying
candle" you see on launch. But the "computer" might have been designed
and built five years before that launch, and minus five years from
today might have meant no PROM or EPROMS were even available at the
time.
1988 or thereabouts the company was overjoyed to finally be able to use silicon, because up till the early 80s silicon simply hadn't been around
long enough to be deemed suitable for long term use (>25yrs).
Rope memory was tried and tested, Fusible link PROMS had no track record
and EEPROMS were definitely subject to ageing
On 6/14/25 7:38 PM, The Natural Philosopher wrote:
On 14/06/2025 17:34, Rich wrote:
Also because (esp. for EPROMS) the rope memory was much moreThere is another issue I ran into. On an undersea cable repeater.
radiation hardened than EPROMS of the day were. Also, for 'long
duration' projects such as that, often each component is designed
and built, then in the end the various parts are pieced together to
produce the "flying candle" you see on launch. But the "computer"
might have been designed and built five years before that launch,
and minus five years from today might have meant no PROM or EPROMS
were even available at the time.
IN 1988 or thereabouts the company was overjoyed to finally be able
to use silicon, because up till the early 80s silicon simply hadn't
been around long enough to be deemed suitable for long term use
25yrs).
Rope memory was tried and tested, Fusible link PROMS had no track
record and EEPROMS were definitely subject to ageing
I'd argue that fuse PROMS didn't NEED a 'track record'
because they're SO straight-up.
UV-EPROMS are also pretty stable (and NOT nearly so sensitive as
some here suggest).
EEPROM was more complicated. Most Flash is even more suspect.
On 6/14/25 12:34 PM, Rich wrote:
c186282 <c186282@nnada.net> wrote:
On 6/13/25 11:35 PM, rbowman wrote:
On Fri, 13 Jun 2025 22:38:38 -0400, c186282 wrote:Ooooh ! Nylon ! EVIL !!! :-)
In any case it's become very clear that a major update is needed for >>>>> the US airport/routing system. Knowing the govt process, the stuff >>>>> will already be obsolete by the time it's installed, but not nearly >>>>> SO obsolete.
In the early '70s we had a contract to build the controllers for the ALS >>>> system. The heart of the controller was an Eagle Signal electromechanical >>>> stepping switch which was pretty much obsolete. The harnesses had to be >>>> laced since the FAA wasn't sure about those new-fangled nylon cable ties. >>>
Not so much that as: Ooooh!, we don't know how well this new "tie"
method will withstand extremes of cold, hot and vibration, and the
current regs. specify "laced" and we *do* know how lacing withstands
extremes of cold, hot and vibration.
Nylon has been around in quantity since the 40s. Somehow I doubt
it's qualities were 'unknown' in the 50s and beyond :-)
MORE likely some senator was vested in a biz that made the older
materials.
There ARE circumstances where 'natural fibers' CAN outperform
plastics - esp at very low temperatures where the plastics become
more brittle.
However those circumstances are few. 'Natural fibers' also tend to
hold MOISTURE - which is bad for HV electricity apps and can lead
to mold/fungi problems.
Also because (esp. for EPROMS) the rope memory was much more
radiation hardened than EPROMS of the day were. Also, for 'long
duration' projects such as that, often each component is designed
and built, then in the end the various parts are pieced together to
produce the "flying candle" you see on launch. But the "computer"
might have been designed and built five years before that launch,
and minus five years from today might have meant no PROM or EPROMS
were even available at the time.
I'd argue about UV-erasable PROMS and space radiation ...
the damned things weren't THAT damned sensitive.
There were also 'fuse PROMS' back then - literal made or broken
wire connections. You CAN still buy them, checked recently. So
long as they're socketed the firmware can be replaced pretty quick
and easy. Low cap by today's standards, but in 1968 or so ...
Nylon has been around in quantity since the 40s. Somehow I doubt it's
qualities were 'unknown'
in the 50s and beyond
MORE likely some senator was vested in a biz that made the older
materials.
There ARE circumstances where 'natural fibers' CAN outperform
plastics - esp at very low temperatures where the plastics become
more brittle. However those circumstances are few. 'Natural fibers'
also tend to hold MOISTURE - which is bad for HV electricity apps and
can lead to mold/fungi problems.
And just what do you have at altitude? Very low temperatures, just
exactly what you state "where the plastics become more brittle":
c186282 <c186282@nnada.net> wrote:
On 6/14/25 12:34 PM, Rich wrote:
c186282 <c186282@nnada.net> wrote:
On 6/13/25 11:35 PM, rbowman wrote:
On Fri, 13 Jun 2025 22:38:38 -0400, c186282 wrote:Ooooh ! Nylon ! EVIL !!! :-)
In any case it's become very clear that a major update is needed for
the US airport/routing system. Knowing the govt process, the stuff >>>>>> will already be obsolete by the time it's installed, but not nearly
SO obsolete.
In the early '70s we had a contract to build the controllers for the ALS >>>>> system. The heart of the controller was an Eagle Signal electromechanical >>>>> stepping switch which was pretty much obsolete. The harnesses had to be >>>>> laced since the FAA wasn't sure about those new-fangled nylon cable ties. >>>>
Not so much that as: Ooooh!, we don't know how well this new "tie"
method will withstand extremes of cold, hot and vibration, and the
current regs. specify "laced" and we *do* know how lacing withstands
extremes of cold, hot and vibration.
Nylon has been around in quantity since the 40s. Somehow I doubt
it's qualities were 'unknown' in the 50s and beyond :-)
What's more likely is its qualities were well known, and known to be unsuitable for use in aircraft wiring harnesses.
MORE likely some senator was vested in a biz that made the older
materials.
In your specific example of aviation wire looms, likely not -- see
below.
There ARE circumstances where 'natural fibers' CAN outperform
plastics - esp at very low temperatures where the plastics become
more brittle.
And just what do you have at altitude? Very low temperatures, just
exactly what you state "where the plastics become more brittle":
https://matmake.com/properties/standard-atmosphere.html
10k-20k feet -> -60C
25k feet (typical passenger aircraft cruse altutude) -> -50C
However those circumstances are few. 'Natural fibers' also tend to
hold MOISTURE - which is bad for HV electricity apps and can lead
to mold/fungi problems.
Yes, that can be a problem, but having your wire loom become brittle at
-60C as you climb through 10k to 20k in altitude and crack apart is not
going to be very good for your aircraft maintaining its intended flight
path.
Also because (esp. for EPROMS) the rope memory was much more
radiation hardened than EPROMS of the day were. Also, for 'long
duration' projects such as that, often each component is designed
and built, then in the end the various parts are pieced together to
produce the "flying candle" you see on launch. But the "computer"
might have been designed and built five years before that launch,
and minus five years from today might have meant no PROM or EPROMS
were even available at the time.
I'd argue about UV-erasable PROMS and space radiation ...
the damned things weren't THAT damned sensitive.
Clearly you are unaware of the kind, and amount, of radiation impact
devices sustain once they are outside the shielded environment here on
the surface. If UV light is energetic enough to erase them in 15
minutes (which was about what it took during their heyday) then there
is way more energetic radiation in space that will wipe your uv-eprom
for you. Keep in mind, these satelites are usually designed for a
multi-year service life (often decades). That means your UV Eprom must
not lose its programming after being bomarded by significant amounts
of radiation for 10 or 20 years -- not just a 15 minute soak. Absent
an actual "radiation hardened" version the standard ones you'd have
been using during the day would not have lasted more than a week or two before their stored program would have been erased.
There were also 'fuse PROMS' back then - literal made or broken
wire connections. You CAN still buy them, checked recently. So
long as they're socketed the firmware can be replaced pretty quick
and easy. Low cap by today's standards, but in 1968 or so ...
Those might have been suitable, at least it is unlikely the space
radiation would have blown an unblown fuse (or reconnected a blown
one). Of course all the read out transistors also have to not be
impacted by the radiation sufficient to produce bit flips, over the
service life of the satelite, for them to be suitable for use.
c186282 <c186282@nnada.net> wrote:
On 6/14/25 7:38 PM, The Natural Philosopher wrote:
On 14/06/2025 17:34, Rich wrote:
Also because (esp. for EPROMS) the rope memory was much moreThere is another issue I ran into. On an undersea cable repeater.
radiation hardened than EPROMS of the day were. Also, for 'long
duration' projects such as that, often each component is designed
and built, then in the end the various parts are pieced together to
produce the "flying candle" you see on launch. But the "computer"
might have been designed and built five years before that launch,
and minus five years from today might have meant no PROM or EPROMS
were even available at the time.
IN 1988 or thereabouts the company was overjoyed to finally be able
to use silicon, because up till the early 80s silicon simply hadn't
been around long enough to be deemed suitable for long term use
25yrs).
Rope memory was tried and tested, Fusible link PROMS had no track
record and EEPROMS were definitely subject to ageing
I'd argue that fuse PROMS didn't NEED a 'track record'
because they're SO straight-up.
While true, that's just not how getting things in space work. They
have to be exposed to the radiation environment they will see in space,
and their success/failure determined from those tests. I.e., they have
to have a "track record".
UV-EPROMS are also pretty stable (and NOT nearly so sensitive as
some here suggest).
Stable here on the surface, where we are shielded from almost all of
the space radiation. But UV-EPROMS work on the same principle as flash
(a charged, insulated, floating gate stores the bits). UV erases them because the UV radiation is energetic enouogh to cause the charge to
drain from the floating gates. Well, guess what, there's lots of
radiation in space that is far more energetic than UV radiation, so
your UV EEPROM will likely lose its stored program (either in short
order, or well before the service lifetime of the satelite it is
installed into). Both of which make it unsuitable.
EEPROM was more complicated. Most Flash is even more suspect.
The only real difference between the UV model and the EE/flash models is
the EE/flash models don't need UV light to initiate the discharge of
the floating gates. But the mechanism of storage is the same in all of
them.
On Sat, 14 Jun 2025 22:41:25 -0400, c186282 wrote:
Nylon has been around in quantity since the 40s. Somehow I doubt it's
qualities were 'unknown'
in the 50s and beyond
MORE likely some senator was vested in a biz that made the older
materials.
There ARE circumstances where 'natural fibers' CAN outperform
plastics - esp at very low temperatures where the plastics become
more brittle. However those circumstances are few. 'Natural fibers'
also tend to hold MOISTURE - which is bad for HV electricity apps and
can lead to mold/fungi problems.
https://www.specialized.net/installation-equipment-supplies/cable- installation/lacing-needles-twine/trueconect-44800nat-lacing-twine-9-ply- waxed-poly-191-yd-spool.html
I don't know what material was used in the '70s but today's lacing twine
is polyester.
I doubt any senator was a lacing twine mogul but ALS for civilian use goes back to the '50s. Bureaucracies are reluctant to change anything. I wonder what new controllers use? You'd probably have to prowl eBay to find Eagle steppers now.
I don't know if the DOT regulations for commercial drivers were updated
but even in the '90s the regulations laid down in the '30s were still in effect. If you followed them religiously you were locked into a 19 hour
cycle that played hell with circadian rhythms.
On 6/15/25 10:19 AM, Rich wrote:
c186282 <c186282@nnada.net> wrote:
On 6/14/25 12:34 PM, Rich wrote:
c186282 <c186282@nnada.net> wrote:
On 6/13/25 11:35 PM, rbowman wrote:
On Fri, 13 Jun 2025 22:38:38 -0400, c186282 wrote:
In any case it's become very clear that a major update is needed for
the US airport/routing system. Knowing the govt process, the stuff
will already be obsolete by the time it's installed, but not nearly
SO obsolete.
In the early '70s we had a contract to build the controllers for the ALS >>>>>> system. The heart of the controller was an Eagle Signal electromechanical
stepping switch which was pretty much obsolete. The harnesses had to be >>>>>> laced since the FAA wasn't sure about those new-fangled nylon cable ties.
Ooooh ! Nylon ! EVIL !!! :-)
Not so much that as: Ooooh!, we don't know how well this new "tie"
method will withstand extremes of cold, hot and vibration, and the
current regs. specify "laced" and we *do* know how lacing withstands
extremes of cold, hot and vibration.
Nylon has been around in quantity since the 40s. Somehow I doubt
it's qualities were 'unknown' in the 50s and beyond :-)
What's more likely is its qualities were well known, and known to be
unsuitable for use in aircraft wiring harnesses.
MORE likely some senator was vested in a biz that made the older
materials.
In your specific example of aviation wire looms, likely not -- see
below.
There ARE circumstances where 'natural fibers' CAN outperform
plastics - esp at very low temperatures where the plastics become
more brittle.
And just what do you have at altitude? Very low temperatures, just
exactly what you state "where the plastics become more brittle":
https://matmake.com/properties/standard-atmosphere.html
10k-20k feet -> -60C
25k feet (typical passenger aircraft cruse altutude) -> -50C
You DO have a fair point here. Not ALL plastics get
brittle, but maybe Nylon does. In any case I'm sure
they're not using hemp string for aircraft harnesses
anymore.
USA, they DID make some revisions about 20 years ago limiting driving
times. The truckers and employers did NOT like it. The tradition was
to push through on strong coffee, sugar and amphetamines, get it
there as fast and direct as possible. One of my first jobs was at a
truck stop complex ... I know
c186282 <c186282@nnada.net> wrote:
On 6/15/25 10:19 AM, Rich wrote:
c186282 <c186282@nnada.net> wrote:
On 6/14/25 12:34 PM, Rich wrote:
c186282 <c186282@nnada.net> wrote:
On 6/13/25 11:35 PM, rbowman wrote:
On Fri, 13 Jun 2025 22:38:38 -0400, c186282 wrote:
In any case it's become very clear that a major update is needed for
the US airport/routing system. Knowing the govt process, the stuff
will already be obsolete by the time it's installed, but not nearly
SO obsolete.
In the early '70s we had a contract to build the controllers for the ALS
system. The heart of the controller was an Eagle Signal electromechanical
stepping switch which was pretty much obsolete. The harnesses had to be >>>>>>> laced since the FAA wasn't sure about those new-fangled nylon cable ties.
Ooooh ! Nylon ! EVIL !!! :-)
Not so much that as: Ooooh!, we don't know how well this new "tie"
method will withstand extremes of cold, hot and vibration, and the
current regs. specify "laced" and we *do* know how lacing withstands >>>>> extremes of cold, hot and vibration.
Nylon has been around in quantity since the 40s. Somehow I doubt
it's qualities were 'unknown' in the 50s and beyond :-)
What's more likely is its qualities were well known, and known to be
unsuitable for use in aircraft wiring harnesses.
MORE likely some senator was vested in a biz that made the older
materials.
In your specific example of aviation wire looms, likely not -- see
below.
There ARE circumstances where 'natural fibers' CAN outperform
plastics - esp at very low temperatures where the plastics become
more brittle.
And just what do you have at altitude? Very low temperatures, just
exactly what you state "where the plastics become more brittle":
https://matmake.com/properties/standard-atmosphere.html
10k-20k feet -> -60C
25k feet (typical passenger aircraft cruse altutude) -> -50C
You DO have a fair point here. Not ALL plastics get
brittle, but maybe Nylon does. In any case I'm sure
they're not using hemp string for aircraft harnesses
anymore.
A little digging indicates that nylon's 'brittleness' temperature is somewhere in the -50C to -60C zone. So the typical temperature of the environment is right in the "brittle zone" for nylon. Then one has to
factor in the impact of vibration (which might cause a not yet fully
brittle nylon tie to shatter at -40C instead of -55C) and I think we
can see why nylon ties might not be aircraft rated.
On Sun, 15 Jun 2025 22:40:00 -0400, c186282 wrote:
USA, they DID make some revisions about 20 years ago limiting driving
times. The truckers and employers did NOT like it. The tradition was
to push through on strong coffee, sugar and amphetamines, get it
there as fast and direct as possible. One of my first jobs was at a
truck stop complex ... I know
Most OTR truckers are paid by the mile which is an incentive to get the
goods delivered and move on to the next load.
https://www.fmcsa.dot.gov/regulations/hours-service/summary-hours-service- regulations
They did switch it up a little. In the '90s you could drive 10 hours with
a half hour break and then had to show 8 hours off. You also had to show
15 minutes for inspection so it came out to 18.75 hours.
We could log 62 mph, or 620 miles for the 10 hours. This was before all
the electronic snooping so you averaged 62 mph, end of story. LA to Denver
is about 1000 miles, or about 16.25 hours driving time. So, in theory, you drove 10 hours and had to take an 8 hour break in Utah, technically at a
rest area on the San Rafael Swell since there is nothing between Salina
and Green River, and I mean nothing. Of course you weren't tired and
couldn't sleep, so after 8 hours of admiring the scenery you could
continue on your merry way.
Or, leave LA early in the morning, drive straight through, get into Denver Sunday afternoon, have supper, and get a good night's sleep after some creative writing in you log book. Ski season sucked because you had the traffic coming back from Vail and the other resorts but 78,000 lbs.
rolling downhill beats a BMW any day.
Diet Coke and Mini-Thins. It was a set back when the ?US banned ephedra around 2001 because some high school jock died after chugging several cans
of energy drink.
On 6/15/25 10:19 AM, Rich wrote:
c186282 <c186282@nnada.net> wrote:
There ARE circumstances where 'natural fibers' CAN outperform
plastics - esp at very low temperatures where the plastics become
more brittle.
And just what do you have at altitude? Very low temperatures, just
exactly what you state "where the plastics become more brittle":
https://matmake.com/properties/standard-atmosphere.html
10k-20k feet -> -60C
25k feet (typical passenger aircraft cruse altutude) -> -50C
You DO have a fair point here. Not ALL plastics get
brittle, but maybe Nylon does. In any case I'm sure
they're not using hemp string for aircraft harnesses
anymore.
There is SOME sane combo of reality and puritan
bullshit out there ... but DON'T expect it to ever
become legal reality. It NEVER works that way.
Took a couple of bennies once ... at Xmas, in a big
shopping mall. It suddenly became SO EASY to weave
through the consumer throngs, like a super-power.
But they're NOT good for you at all.
Umm ... we seem to have departed Linux again .....
On 2025-06-16, c186282 <c186282@nnada.net> wrote:
On 6/15/25 10:19 AM, Rich wrote:
c186282 <c186282@nnada.net> wrote:
There ARE circumstances where 'natural fibers' CAN outperform
plastics - esp at very low temperatures where the plastics become
more brittle.
And just what do you have at altitude? Very low temperatures, just
exactly what you state "where the plastics become more brittle":
https://matmake.com/properties/standard-atmosphere.html
10k-20k feet -> -60C
25k feet (typical passenger aircraft cruse altutude) -> -50C
You missed the notation on the chart: those altitudes are in
meters, not feet.
Basically, the standard atmosphere specifies a temperature of 15C at
sea level, decreasing by 2C per 1000 feet up to the tropopause, which
is typically around 35,000 feet. There the temperature levels off at
about -55C and stays there up to well beyond the service ceiling of
any aeroplane (as opposed to rocket). In real life these numbers
vary, and aviation weather stations provide forecasts of actual
conditions in the current time frame.
Still, given that airliners cruise at 25,000 to 40,000 feet,
they're exposed to some pretty intense cold.
You DO have a fair point here. Not ALL plastics get brittle, but
maybe Nylon does. In any case I'm sure they're not using hemp
string for aircraft harnesses anymore.
Yesterday I felt a something catching while moving the controls in
our small plane. I found that various bits of plumbing behind the
panel had shifted to where they were touching things they shouldn't.
Time to get out those good old nylon zap straps and tie things back
where they belong, just like the mechanics do. Mind you, we don't
get much above 10,000 feet...
On 6/15/25 11:00 PM, Rich wrote:
A little digging indicates that nylon's 'brittleness' temperature is
somewhere in the -50C to -60C zone. So the typical temperature of
the environment is right in the "brittle zone" for nylon. Then one
has to factor in the impact of vibration (which might cause a not
yet fully brittle nylon tie to shatter at -40C instead of -55C) and
I think we can see why nylon ties might not be aircraft rated.
Borderline ... but perhaps relevant. Maybe not SO much for
commercial craft, but decidedly for military and space apps.
Other sources say that polyester cord has become the modern
standard. I've seen some info that says many polyesters are good
to about -100c. Good for aircraft, good for antarctic gear.
On Sat, 14 Jun 2025 00:29:12 -0400
c186282 <c186282@nnada.net> wrote:
I've done TMS-9900 programming ... odd but interesting chip. Seems to
have evolved when there was little diff between on-chip cache memory
and main memory (not the tech to PUT a lot of ram into the CPU
either). Also had a sort of hardware solution to multi-user/multi-
processing which was very unique. Still remember "BLWP" - Branch And
Load Workspace Pointer". The 990 minis weren't so bad.
Always found that one intriguing. Yeah, like the 6502's zero-page, it's
a design from a different era as far as CPU-vs.-RAM-speed goes, but a
clever design-around for fairly elegant multi-tasking in light of it. Oneathesedays I wanna take one of the later iterations (the TMS99105,
IIRC, is the last one that kept the memory-resident register-file
property; some later TI microcontrollers borrow the basic architecture,
but ditch that) and throw together a little homebrew hobbyist system...
On 2025-06-16, c186282 <c186282@nnada.net> wrote:
On 6/15/25 10:19 AM, Rich wrote:
c186282 <c186282@nnada.net> wrote:
There ARE circumstances where 'natural fibers' CAN outperform
plastics - esp at very low temperatures where the plastics become
more brittle.
And just what do you have at altitude? Very low temperatures, just
exactly what you state "where the plastics become more brittle":
https://matmake.com/properties/standard-atmosphere.html
10k-20k feet -> -60C
25k feet (typical passenger aircraft cruse altutude) -> -50C
You missed the notation on the chart: those altitudes are in
meters, not feet. Basically, the standard atmosphere specifies
a temperature of 15C at sea level, decreasing by 2C per 1000
feet up to the tropopause, which is typically around 35,000
feet. There the temperature levels off at about -55C and stays
there up to well beyond the service ceiling of any aeroplane
(as opposed to rocket). In real life these numbers vary, and
aviation weather stations provide forecasts of actual conditions
in the current time frame.
Still, given that airliners cruise at 25,000 to 40,000 feet,
they're exposed to some pretty intense cold.
You DO have a fair point here. Not ALL plastics get
brittle, but maybe Nylon does. In any case I'm sure
they're not using hemp string for aircraft harnesses
anymore.
Yesterday I felt a something catching while moving the controls
in our small plane. I found that various bits of plumbing
behind the panel had shifted to where they were touching things
they shouldn't. Time to get out those good old nylon zap straps
and tie things back where they belong, just like the mechanics do.
Mind you, we don't get much above 10,000 feet...
John Ames <commodorejohn@gmail.com> wrote:
On Sat, 14 Jun 2025 00:29:12 -0400
c186282 <c186282@nnada.net> wrote:
I've done TMS-9900 programming ... odd but interesting chip. Seems to
have evolved when there was little diff between on-chip cache memory
and main memory (not the tech to PUT a lot of ram into the CPU
either). Also had a sort of hardware solution to multi-user/multi-
processing which was very unique. Still remember "BLWP" - Branch And
Load Workspace Pointer". The 990 minis weren't so bad.
Always found that one intriguing. Yeah, like the 6502's zero-page, it's
a design from a different era as far as CPU-vs.-RAM-speed goes, but a
clever design-around for fairly elegant multi-tasking in light of it.
Oneathesedays I wanna take one of the later iterations (the TMS99105,
IIRC, is the last one that kept the memory-resident register-file
property; some later TI microcontrollers borrow the basic architecture,
but ditch that) and throw together a little homebrew hobbyist system...
A similar effect played out in the HP3000 stack based CPU systems [1]
The stack was kept in memory, and the CPU only had "registers" for the
top two, four or eight stack slots.
But reality was that all the way up until somewhere around the iapx286
time range, RAM memory was faster than the CPU's it was attached to, so
large register files on the CPU, or giant caches, were not needed. The
CPU was as fast as it was, and the RAM wasn't what was holding it back.
After sometime around the 286 time range, CPU speed started greatly
outpacing RAM speed and large on chip register files and caches (the
bigger the better) came into play.
[1] https://en.wikipedia.org/wiki/HP3000#Use_of_stack_instead_of_registers
On 6/16/25 1:52 PM, Charlie Gibbs wrote:
Yesterday I felt a something catching while moving the controls
in our small plane. I found that various bits of plumbing
behind the panel had shifted to where they were touching things
they shouldn't. Time to get out those good old nylon zap straps
and tie things back where they belong, just like the mechanics do.
Mind you, we don't get much above 10,000 feet...
Always MANY failure modes alas ...
However AIRLINE corps are SUPPOSED to keep abreast
and ahead of these issues.
About the time I quit flying was during a huge OPEC
oil embargo. Fuel prices quadrupled or more and too
often you couldn't even GET the right fuel for the
planes. Valve lock in a 4-cyl engine - NOT good.
Green gas was NOT red gas !
I hear they've now recovered both boxes from the
crashed plane. In maybe a week we'll at least get
a preliminary report.
SEEMS like some kind of software error - the big
engines just wouldn't produce the needed power.
The pilots didn't have enough time to maybe fix it.
Boom.
Dunno what gods the one survivor prays to - but :-)
You missed the notation on the chart: those altitudes are in meters, not feet.
On Mon, 16 Jun 2025 17:52:09 GMT, Charlie Gibbs wrote:
You missed the notation on the chart: those altitudes are in meters, not
feet.
We call them “metres”. Since when do we use Yank spelling for units that Yanks don’t even use anyway?
On 2025-06-17, c186282 <c186282@nnada.net> wrote:
On 6/16/25 1:52 PM, Charlie Gibbs wrote:
Yesterday I felt a something catching while moving the controls
in our small plane. I found that various bits of plumbing
behind the panel had shifted to where they were touching things
they shouldn't. Time to get out those good old nylon zap straps
and tie things back where they belong, just like the mechanics do.
Mind you, we don't get much above 10,000 feet...
Always MANY failure modes alas ...
However AIRLINE corps are SUPPOSED to keep abreast
and ahead of these issues.
<cough>Boeing<cough>
About the time I quit flying was during a huge OPEC
oil embargo. Fuel prices quadrupled or more and too
often you couldn't even GET the right fuel for the
planes. Valve lock in a 4-cyl engine - NOT good.
Green gas was NOT red gas !
And now it's replaced by blue gas - 100LL (low lead).
Much less lead than good old green gas (100/130), but
still three times as much as in the red gas (80/87)
that a lot of engines were designed for. Beware of
lead fouling the plugs!
I hear they've now recovered both boxes from the
crashed plane. In maybe a week we'll at least get
a preliminary report.
That'll be good to hear. Until then, it's just ignorant
talking heads on the news, with nothing to fill their
time slot but idle speculation and improvised crap.
SEEMS like some kind of software error - the big
engines just wouldn't produce the needed power.
The pilots didn't have enough time to maybe fix it.
Boom.
Dunno what gods the one survivor prays to - but :-)
That was pretty amazing. I bet the seat he was sitting in
(well, one in the same position) will command a hefty premium
on future 787 flights.
On Mon, 16 Jun 2025 17:52:09 GMT, Charlie Gibbs wrote:
You missed the notation on the chart: those altitudes are in meters, not
feet.
We call them “metres”. Since when do we use Yank spelling for units that Yanks don’t even use anyway?
On Sat, 14 Jun 2025 00:29:12 -0400
c186282 <c186282@nnada.net> wrote:
I've done TMS-9900 programming ... odd but interesting chip. Seems to
have evolved when there was little diff between on-chip cache memory
and main memory (not the tech to PUT a lot of ram into the CPU
either). Also had a sort of hardware solution to multi-user/multi-
processing which was very unique. Still remember "BLWP" - Branch And
Load Workspace Pointer". The 990 minis weren't so bad.
Always found that one intriguing. Yeah, like the 6502's zero-page, it's
a design from a different era as far as CPU-vs.-RAM-speed goes, but a
clever design-around for fairly elegant multi-tasking in light of it. Oneathesedays I wanna take one of the later iterations (the TMS99105,
IIRC, is the last one that kept the memory-resident register-file
property; some later TI microcontrollers borrow the basic architecture,
but ditch that) and throw together a little homebrew hobbyist system...
Meters, metres (my spellcheck doesn't like that)
are convenient, but centimeters/millimeters are too small - the
English units are more, well, 'human scale'.
On 6/17/25 2:20 PM, Charlie Gibbs wrote:
On 2025-06-17, c186282 <c186282@nnada.net> wrote:
On 6/16/25 1:52 PM, Charlie Gibbs wrote:
Yesterday I felt a something catching while moving the controls
in our small plane. I found that various bits of plumbing
behind the panel had shifted to where they were touching things
they shouldn't. Time to get out those good old nylon zap straps
and tie things back where they belong, just like the mechanics do.
Mind you, we don't get much above 10,000 feet...
Always MANY failure modes alas ...
However AIRLINE corps are SUPPOSED to keep abreast
and ahead of these issues.
<cough>Boeing<cough>
About the time I quit flying was during a huge OPEC
oil embargo. Fuel prices quadrupled or more and too
often you couldn't even GET the right fuel for the
planes. Valve lock in a 4-cyl engine - NOT good.
Green gas was NOT red gas !
And now it's replaced by blue gas - 100LL (low lead).
Much less lead than good old green gas (100/130), but
still three times as much as in the red gas (80/87)
that a lot of engines were designed for. Beware of
lead fouling the plugs!
In the 70s, engines made for Red did NOT take
well to 100LL. It was both ignition and
especially the VALVES. KEPT having valves
stick ... NOT good. Besides, oil embargoes
drove fuel prices through the roof - could
NOT afford it then.
On 18 Jun 2025 03:55:32 GMT
rbowman <bowman@montana.com> wrote:
Besides 'metre' goes back to the French National Assembly that wanted
to reinvent everything including 10 day weeks with the days named
after plants.
Frustratingly, the year persisted in having 365.25[...] days no matter
how severely they threatened to guillotine it ;)
Frustratingly, the year persisted in having 365.25[...] days no matter
how severely they threatened to guillotine it ;)
On 2025-06-18, John Ames <commodorejohn@gmail.com> wrote:
On 18 Jun 2025 03:55:32 GMT
rbowman <bowman@montana.com> wrote:
Besides 'metre' goes back to the French National Assembly that wanted
to reinvent everything including 10 day weeks with the days named
after plants.
Frustratingly, the year persisted in having 365.25[...] days no matter
how severely they threatened to guillotine it ;)
Just as pi has resisted any attempts to re-define it as 3.
(355/113 works pretty well, though...)
In comp.os.linux.misc c186282 <c186282@nnada.net> wrote:
On 6/17/25 2:20 PM, Charlie Gibbs wrote:
On 2025-06-17, c186282 <c186282@nnada.net> wrote:
On 6/16/25 1:52 PM, Charlie Gibbs wrote:
Yesterday I felt a something catching while moving the controls
in our small plane. I found that various bits of plumbing
behind the panel had shifted to where they were touching things
they shouldn't. Time to get out those good old nylon zap straps
and tie things back where they belong, just like the mechanics do.
Mind you, we don't get much above 10,000 feet...
Always MANY failure modes alas ...
However AIRLINE corps are SUPPOSED to keep abreast
and ahead of these issues.
<cough>Boeing<cough>
About the time I quit flying was during a huge OPEC
oil embargo. Fuel prices quadrupled or more and too
often you couldn't even GET the right fuel for the
planes. Valve lock in a 4-cyl engine - NOT good.
Green gas was NOT red gas !
And now it's replaced by blue gas - 100LL (low lead).
Much less lead than good old green gas (100/130), but
still three times as much as in the red gas (80/87)
that a lot of engines were designed for. Beware of
lead fouling the plugs!
In the 70s, engines made for Red did NOT take
well to 100LL. It was both ignition and
especially the VALVES. KEPT having valves
stick ... NOT good. Besides, oil embargoes
drove fuel prices through the roof - could
NOT afford it then.
Was 'red' a leaded fuel? Tetraethyl lead as a gasoline additive
provided more than simply an octane boost. The leftover residue from combustion provided a lubricating effect, and as a result for many
(most?) engines designed in the days of leaded fuel the designers took advantage of that lubricating effect from the tetraethyl lead for (at
least) the valve stems (esp. the exhaust valve, which operated at temperatures that made only oil lubrication difficult) and for
cushioning the valve seats when the valves closed. When running
unleaded fuel in an engine that took advantage if the lead lubrication effect, eventually one got stuck valves or very worn valve seats.
On 6/18/25 12:15 PM, Charlie Gibbs wrote:
On 2025-06-18, John Ames <commodorejohn@gmail.com> wrote:
On 18 Jun 2025 03:55:32 GMT
rbowman <bowman@montana.com> wrote:
Besides 'metre' goes back to the French National Assembly that wanted
to reinvent everything including 10 day weeks with the days named
after plants.
Frustratingly, the year persisted in having 365.25[...] days no matter
how severely they threatened to guillotine it ;)
Just as pi has resisted any attempts to re-define it as 3.
(355/113 works pretty well, though...)
Well, just change to base-pi ... then it's
conveniently 1
Might be a bit messy to calculate how to make
change at the convenience store however :-)
Yeah, and then you have all those people who just got converted to base
e and don't want to change again.
On 2025-06-18, c186282 <c186282@nnada.net> wrote:
On 6/18/25 12:15 PM, Charlie Gibbs wrote:
On 2025-06-18, John Ames <commodorejohn@gmail.com> wrote:
On 18 Jun 2025 03:55:32 GMT
rbowman <bowman@montana.com> wrote:
Besides 'metre' goes back to the French National Assembly that wanted >>>>> to reinvent everything including 10 day weeks with the days named
after plants.
Frustratingly, the year persisted in having 365.25[...] days no matter >>>> how severely they threatened to guillotine it ;)
Just as pi has resisted any attempts to re-define it as 3.
(355/113 works pretty well, though...)
Well, just change to base-pi ... then it's
conveniently 1
Might be a bit messy to calculate how to make
change at the convenience store however :-)
Yeah, and then you have all those people who just got converted
to base e and don't want to change again.
Programmers use base-16.
On Fri, 20 Jun 2025 08:36:57 -0400, Chris Ahlstrom wrote:
Programmers use base-16.
And 2, 8, and 10. ARM processors are bringing bit twiddling back into
style.
On Fri, 20 Jun 2025 08:36:57 -0400, Chris Ahlstrom wrote:
Programmers use base-16.
And 2, 8, and 10. ARM processors are bringing bit twiddling back into
style.
rbowman wrote this post while blinking in Morse code:
On Fri, 20 Jun 2025 08:36:57 -0400, Chris Ahlstrom wrote:
Programmers use base-16.
And 2, 8, and 10. ARM processors are bringing bit twiddling back into
style.
Dang, I forgot about base 2!
Base 8 is kind of annoying, you know.
rbowman wrote this post while blinking in Morse code:
On Fri, 20 Jun 2025 08:36:57 -0400, Chris Ahlstrom wrote:
Programmers use base-16.
And 2, 8, and 10. ARM processors are bringing bit twiddling back into
style.
Dang, I forgot about base 2!
Base 8 is kind of annoying, you know.
On 2025-06-21, Chris Ahlstrom <OFeem1987@teleworm.us> wrote:
rbowman wrote this post while blinking in Morse code:
On Fri, 20 Jun 2025 08:36:57 -0400, Chris Ahlstrom wrote:
Programmers use base-16.
And 2, 8, and 10. ARM processors are bringing bit twiddling back into
style.
Dang, I forgot about base 2!
There are 10 kinds of people:
those who understand binary and those who don't.
Base 8 is kind of annoying, you know.
"Base 8 is just like base 10, really - if you're missing two fingers."
-- Tom Lehrer
On Sat, 21 Jun 2025 23:57:23 GMT, Charlie Gibbs wrote:
On 2025-06-21, Chris Ahlstrom <OFeem1987@teleworm.us> wrote:
rbowman wrote this post while blinking in Morse code:
On Fri, 20 Jun 2025 08:36:57 -0400, Chris Ahlstrom wrote:
Programmers use base-16.
And 2, 8, and 10. ARM processors are bringing bit twiddling back into >>>> style.
Dang, I forgot about base 2!
There are 10 kinds of people:
those who understand binary and those who don't.
Base 8 is kind of annoying, you know.
"Base 8 is just like base 10, really - if you're missing two fingers."
-- Tom Lehrer
It sounds far-fetched but supposedly one culture used base 8 because they counted with the spaces between their fingers rather than their fingers.
Still wonder about the Babylonian base-60 thing ...
On 2025-06-21, Chris Ahlstrom <OFeem1987@teleworm.us> wrote:
rbowman wrote this post while blinking in Morse code:
On Fri, 20 Jun 2025 08:36:57 -0400, Chris Ahlstrom wrote:
Programmers use base-16.
And 2, 8, and 10. ARM processors are bringing bit twiddling back into
style.
Dang, I forgot about base 2!
There are 10 kinds of people:
those who understand binary and those who don't.
Base 8 is kind of annoying, you know.
"Base 8 is just like base 10, really - if you're missing two fingers."
-- Tom Lehrer
On Sat, 21 Jun 2025 21:24:07 -0400, c186282 wrote:
Still wonder about the Babylonian base-60 thing ...
Yeah, every time I have to convert degrees/minutes/seconds into something
I can work with. The jury is still out if that can be blamed on them or
not. The French tried to metrify that and more or less failed.
On Sat, 21 Jun 2025 23:57:23 GMT, Charlie Gibbs wrote:
On 2025-06-21, Chris Ahlstrom <OFeem1987@teleworm.us> wrote:
rbowman wrote this post while blinking in Morse code:
On Fri, 20 Jun 2025 08:36:57 -0400, Chris Ahlstrom wrote:
Programmers use base-16.
And 2, 8, and 10. ARM processors are bringing bit twiddling back into >>>> style.
Dang, I forgot about base 2!
There are 10 kinds of people:
those who understand binary and those who don't.
Base 8 is kind of annoying, you know.
"Base 8 is just like base 10, really - if you're missing two fingers."
-- Tom Lehrer
It sounds far-fetched but supposedly one culture used base 8 because they counted with the spaces between their fingers rather than their fingers.
On Sat, 21 Jun 2025 06:50:53 -0400, Chris Ahlstrom wrote:
rbowman wrote this post while blinking in Morse code:
On Fri, 20 Jun 2025 08:36:57 -0400, Chris Ahlstrom wrote:
Programmers use base-16.
And 2, 8, and 10. ARM processors are bringing bit twiddling back into
style.
Dang, I forgot about base 2!
Base 8 is kind of annoying, you know.
For some processors octal works well for opcodes. Then there is chmod and friends.
On Sat, 21 Jun 2025 21:24:07 -0400, c186282 wrote:
Still wonder about the Babylonian base-60 thing ...
Yeah, every time I have to convert degrees/minutes/seconds into something
I can work with. The jury is still out if that can be blamed on them or
not. The French tried to metrify that and more or less failed.
On Sat, 21 Jun 2025 23:57:23 GMT, Charlie Gibbs wrote:
On 2025-06-21, Chris Ahlstrom <OFeem1987@teleworm.us> wrote:
rbowman wrote this post while blinking in Morse code:
On Fri, 20 Jun 2025 08:36:57 -0400, Chris Ahlstrom wrote:
Programmers use base-16.
And 2, 8, and 10. ARM processors are bringing bit twiddling back into >>>> style.
Dang, I forgot about base 2!
There are 10 kinds of people:
those who understand binary and those who don't.
Base 8 is kind of annoying, you know.
"Base 8 is just like base 10, really - if you're missing two fingers."
-- Tom Lehrer
It sounds far-fetched but supposedly one culture used base 8 because they counted with the spaces between their fingers rather than their fingers.
On 6/22/25 2:14 AM, rbowman wrote:
On Sat, 21 Jun 2025 21:24:07 -0400, c186282 wrote:
Still wonder about the Babylonian base-60 thing ...
Yeah, every time I have to convert degrees/minutes/seconds into something
I can work with. The jury is still out if that can be blamed on them or
not. The French tried to metrify that and more or less failed.
It WAS a really weird system for sure.
PROBABLY based on 360 degrees, but we
can't be sure. '
Odd factoid, the old Greek scientists had
to change their crap number system to
Babylonian, do the calx, then convert
back to the Greek system.
Anyway, 60 different numbers ... likely twice
as many symbols as needed to write the main lang.
Wow.
On 22/06/2025 07:14, rbowman wrote:
On Sat, 21 Jun 2025 21:24:07 -0400, c186282 wrote:
Still wonder about the Babylonian base-60 thing ...
Yeah, every time I have to convert degrees/minutes/seconds into something
I can work with. The jury is still out if that can be blamed on them or
not. The French tried to metrify that and more or less failed.
Even Socialism cant make the year 1000 days long
On 2025-06-22, c186282 <c186282@nnada.net> wrote:
On 6/22/25 2:14 AM, rbowman wrote:
On Sat, 21 Jun 2025 21:24:07 -0400, c186282 wrote:
Still wonder about the Babylonian base-60 thing ...
Yeah, every time I have to convert degrees/minutes/seconds into
something I can work with. The jury is still out if that can be blamed
on them or not. The French tried to metrify that and more or less
failed.
It WAS a really weird system for sure.
PROBABLY based on 360 degrees, but we can't be sure. '
Odd factoid, the old Greek scientists had to change their crap
number system to Babylonian, do the calx, then convert back to the
Greek system.
Anyway, 60 different numbers ... likely twice as many symbols as
needed to write the main lang.
Wow.
And then there's base-64...
On 2025-06-22, rbowman <bowman@montana.com> wrote:
On Sat, 21 Jun 2025 21:24:07 -0400, c186282 wrote:
Still wonder about the Babylonian base-60 thing ...
Yeah, every time I have to convert degrees/minutes/seconds into
something I can work with. The jury is still out if that can be blamed
on them or not. The French tried to metrify that and more or less
failed.
Fortunately, my GPS (thank you, Garmin!) lets me select the notation
when entering latitude and longitude. Some sources write it as degrees/minutes/seconds, some use degrees/minutes with decimals, some
use decimal degrees.
We allowed users to configure the display values to decimal degrees,
minutes, or seconds as well as UTM and USNG but the values were stored as double in decimal degrees. Your average dispatcher has no idea where any
of them are.
If you want to have real fun with your Garmin set the datum to NAD27.
When he first started a geocacher was using that instead of WGS 84. The coordinates were about 100 yards away, which is fun when you're looking
for a hidden ammo can on the side of a mountain.
Decimal degrees do make number crunching a lot easier.
If you want to have real fun with your Garmin set the datum to
NAD27. When he first started a geocacher was using that instead of
WGS 84. The coordinates were about 100 yards away, which is fun
when you're looking for a hidden ammo can on the side of a
mountain.
On 2025-06-22, c186282 <c186282@nnada.net> wrote:
On 6/22/25 2:14 AM, rbowman wrote:
On Sat, 21 Jun 2025 21:24:07 -0400, c186282 wrote:
Still wonder about the Babylonian base-60 thing ...
Yeah, every time I have to convert degrees/minutes/seconds into something >>> I can work with. The jury is still out if that can be blamed on them or
not. The French tried to metrify that and more or less failed.
It WAS a really weird system for sure.
PROBABLY based on 360 degrees, but we
can't be sure. '
Odd factoid, the old Greek scientists had
to change their crap number system to
Babylonian, do the calx, then convert
back to the Greek system.
Anyway, 60 different numbers ... likely twice
as many symbols as needed to write the main lang.
Wow.
And then there's base-64...
On 2025-06-22, The Natural Philosopher <tnp@invalid.invalid> wrote:
On 22/06/2025 07:14, rbowman wrote:
On Sat, 21 Jun 2025 21:24:07 -0400, c186282 wrote:
Still wonder about the Babylonian base-60 thing ...
Yeah, every time I have to convert degrees/minutes/seconds into something >>> I can work with. The jury is still out if that can be blamed on them or
not. The French tried to metrify that and more or less failed.
Even Socialism cant make the year 1000 days long
It can make it seem like it.
Of course, the same is true of any ideology taken to extremes...
On Sun, 22 Jun 2025 21:55:47 GMT, Charlie Gibbs wrote:
Decimal degrees do make number crunching a lot easier.
Trig calculations are most easily done in radians.
If you want to have real fun with your Garmin set the datum to
NAD27. When he first started a geocacher was using that instead of
WGS 84. The coordinates were about 100 yards away, which is fun
when you're looking for a hidden ammo can on the side of a
mountain.
That 100 yards sounds about right for the distance between Greenwich Observatory and the current location of the 0° longitude line ...
On Sun, 22 Jun 2025 21:55:47 GMT, Charlie Gibbs wrote:
Decimal degrees do make number crunching a lot easier.
Trig calculations are most easily done in radians.
If you want to have real fun with your Garmin set the datum to NAD27.
When he first started a geocacher was using that instead of WGS 84.
The coordinates were about 100 yards away, which is fun when you're
looking for a hidden ammo can on the side of a mountain.
That 100 yards sounds about right for the distance between Greenwich Observatory and the current location of the 0° longitude line ...
I've written call accounting software for local 911 centres. The
switches give us latitude and longitude in degrees with six decimals.
That narrows it down to about 4 inches, which seems a bit optimistic,
unless you somehow have access to a differential GPS setup.
A friend
who calibrated aeronautical navaids before he retired told me how they'd
set up a differential GPS transmitter at an airport and get 1-centimeter accuracy while flying an approach.
(Worst-case WAAS is 20 feet vertically, less horizontally - competitive
with ILS.)
Years ago Trimble was a big player when emergency services started using
AVL and they had their own format. Geocom, another player, sent the coordinated in hex. It's been a long time but there was also a magic
number involved where x and y were the hex values.
*lat = (double) x * 5.729577957 * .0000001;
*lon = (double) y * 5.729577957 * .0000001;
Six decimal places in a double might imply accuracy that isn't really
there, but you definitely don't want to try to cram it into a float and expect a happy ending when you start your conversions.
But yea, the universe rarely cooperates with 'logical'
systems humans might try to devise. Remember the old Greeks and their
obsession with 'perfect' circular motion in the cosmos ? The cosmos
was supposed to be 'divine', and therefore only 'perfect' geometry
would be seen.
On 6/22/25 11:49 AM, Charlie Gibbs wrote:
On 2025-06-22, c186282 <c186282@nnada.net> wrote:
On 6/22/25 2:14 AM, rbowman wrote:
On Sat, 21 Jun 2025 21:24:07 -0400, c186282 wrote:
Still wonder about the Babylonian base-60 thing ...
Yeah, every time I have to convert degrees/minutes/seconds into
something I can work with. The jury is still out if that can be
blamed on them or not. The French tried to metrify that and more or
less failed.
It WAS a really weird system for sure.
PROBABLY based on 360 degrees, but we can't be sure. '
Odd factoid, the old Greek scientists had to change their crap
number system to Babylonian, do the calx, then convert back to the
Greek system.
Anyway, 60 different numbers ... likely twice as many symbols as
needed to write the main lang.
Wow.
And then there's base-64...
Don't see that often ...
On 2025-06-23, rbowman <bowman@montana.com> wrote:
Years ago Trimble was a big player when emergency services started
using AVL and they had their own format. Geocom, another player, sent
the coordinated in hex. It's been a long time but there was also a
magic number involved where x and y were the hex values.
*lat = (double) x * 5.729577957 * .0000001;
*lon = (double) y * 5.729577957 * .0000001;
That number looks suspiciously like the number of degrees in a radian, divided by 10.
... 60 is a number with a nice complement of small factors:
2 * 2 * 3 * 5
which makes it evenly divisible by:
2, 3, 4, 5, 6, 10, 12, 15, 20, 30
Many of the world's ills are caused by people using floating point when
they really shouldn't. "Oh, there's a decimal in dollar amounts;
that means we _must_ use floating point." They obviously never heard of decimal pennies (or suitable fractions of pennies).
On Mon, 23 Jun 2025 01:01:45 -0400, c186282 wrote:
But yea, the universe rarely cooperates with 'logical'
systems humans might try to devise. Remember the old Greeks and their
obsession with 'perfect' circular motion in the cosmos ? The cosmos
was supposed to be 'divine', and therefore only 'perfect' geometry
would be seen.
The universe laughs as humans invent arbitrary systems to explain it, and then pride themselves on how consistent their inventions are.
On Mon, 23 Jun 2025 16:43:35 GMT, Charlie Gibbs wrote:
Many of the world's ills are caused by people using floating point when
they really shouldn't. "Oh, there's a decimal in dollar amounts;
that means we _must_ use floating point." They obviously never heard of
decimal pennies (or suitable fractions of pennies).
Remember that, in the current IEEE 754 spec, floating-point can be decimal
or binary.
Very few languages include fixed-point types (with a fractional part) as standard -- Ada being an exception, as I recall.
On Mon, 23 Jun 2025 16:43:35 GMT, Charlie Gibbs wrote:
Many of the world's ills are caused by people using floating point when
they really shouldn't. "Oh, there's a decimal in dollar amounts;
that means we _must_ use floating point." They obviously never heard of
decimal pennies (or suitable fractions of pennies).
Remember that, in the current IEEE 754 spec, floating-point can be decimal
or binary.
Very few languages include fixed-point types (with a fractional part) as standard -- Ada being an exception, as I recall.
On 2025-06-23, rbowman <bowman@montana.com> wrote:
On Mon, 23 Jun 2025 01:01:45 -0400, c186282 wrote:
But yea, the universe rarely cooperates with 'logical'
systems humans might try to devise. Remember the old Greeks and
their obsession with 'perfect' circular motion in the cosmos ? The
cosmos was supposed to be 'divine', and therefore only 'perfect'
geometry would be seen.
The universe laughs as humans invent arbitrary systems to explain it,
and then pride themselves on how consistent their inventions are.
Irrational numbers must drive those people nuts.
On 2025-06-23, rbowman <bowman@montana.com> wrote:
On Mon, 23 Jun 2025 01:01:45 -0400, c186282 wrote:
But yea, the universe rarely cooperates with 'logical'
systems humans might try to devise. Remember the old Greeks and their >>> obsession with 'perfect' circular motion in the cosmos ? The cosmos
was supposed to be 'divine', and therefore only 'perfect' geometry
would be seen.
The universe laughs as humans invent arbitrary systems to explain it, and
then pride themselves on how consistent their inventions are.
Irrational numbers must drive those people nuts.
Irrational numbers must drive those people nuts.
On 2025-06-24, Lawrence D'Oliveiro <ldo@nz.invalid> wrote:
Very few languages include fixed-point types (with a fractional part)
as standard -- Ada being an exception, as I recall.
Meanwhile we have to fake it:
printf("%8ld.%02d\n", amount / 100L, amount % 100L);
Handling negative amounts is left as an exercise for the user.
On Mon, 23 Jun 2025 01:01:45 -0400, c186282 wrote:Indeed it does.
But yea, the universe rarely cooperates with 'logical'
systems humans might try to devise. Remember the old Greeks and their
obsession with 'perfect' circular motion in the cosmos ? The cosmos
was supposed to be 'divine', and therefore only 'perfect' geometry
would be seen.
The universe laughs as humans invent arbitrary systems to explain it, and then pride themselves on how consistent their inventions are.
The universe laughs as humans invent arbitrary systems to explain it,
and then pride themselves on how consistent their inventions are.
Indeed it does.
On Tue, 24 Jun 2025 01:34:54 -0000 (UTC)
Lawrence D'Oliveiro <ldo@nz.invalid> wrote:
2, 3, 4, 5, 6, 10, 12, 15, 20, 30
Base 30 (= 2 × 3 × 5) has exactly the same exact divisors.
There is no point in repeating prime factors in the base.
30 / 4 = ...?
30 / 12 = ...?
30 / 20 = ...?
On Tue, 24 Jun 2025 10:19:55 +0100, The Natural Philosopher wrote:
The universe laughs as humans invent arbitrary systems to explain it,
and then pride themselves on how consistent their inventions are.
Indeed it does.
That’s a very ... um ... anthropomorphic mentality ...
On Tue, 24 Jun 2025 22:25:45 -0000 (UTC), Lawrence D'Oliveiro wrote:
On Tue, 24 Jun 2025 10:19:55 +0100, The Natural Philosopher wrote:
The universe laughs as humans invent arbitrary systems to explain it,
and then pride themselves on how consistent their inventions are.
Indeed it does.
That’s a very ... um ... anthropomorphic mentality ...
It's the Zen catch-22. The chatter invented by humans is inadequate for expressing reality so you do the best you can.
On Tue, 24 Jun 2025 10:19:55 +0100, The Natural Philosopher wrote:
The universe laughs as humans invent arbitrary systems to explain it,
and then pride themselves on how consistent their inventions are.
Indeed it does.
That’s a very ... um ... anthropomorphic mentality ...
On Tue, 24 Jun 2025 22:24:57 -0000 (UTC)
Lawrence D'Oliveiro <ldo@nz.invalid> wrote:
30 / 4 = ...?
30 / 12 = ...?
30 / 20 = ...?
Using letters a .. t to represent the 20 additional digits, in base-30
these become
10 ÷ 4 = 7.f0
10 ÷ c = 2.f0
10 ÷ k = 0.f0
Try something a bit less simplistic?
1 ÷ 3 = 0.a
All these fractions are exact -- no repeating digits.
Gotcha - that does strictly fit what I said, but I guess I was thinking
of even divisibility (no fractions needed for a fairly common divisor)
as an additional point of convenience.
On Mon, 23 Jun 2025 11:27:13 -0700, John Ames wrote:
... 60 is a number with a nice complement of small factors:
2 * 2 * 3 * 5
which makes it evenly divisible by:
2, 3, 4, 5, 6, 10, 12, 15, 20, 30
Base 30 (= 2 × 3 × 5) has exactly the same exact divisors.
On Di 24 Jun 2025 at 01:34, Lawrence D'Oliveiro <ldo@nz.invalid> wrote:
On Mon, 23 Jun 2025 11:27:13 -0700, John Ames wrote:
... 60 is a number with a nice complement of small factors:
2 * 2 * 3 * 5
which makes it evenly divisible by:
2, 3, 4, 5, 6, 10, 12, 15, 20, 30
Base 30 (= 2 × 3 × 5) has exactly the same exact divisors.
Well, not quite - 20 ist *not* a divisor of 30.
On 6/21/25 7:57 PM, Charlie Gibbs wrote:
On 2025-06-21, Chris Ahlstrom <OFeem1987@teleworm.us> wrote:
rbowman wrote this post while blinking in Morse code:
On Fri, 20 Jun 2025 08:36:57 -0400, Chris Ahlstrom wrote:
Programmers use base-16.
And 2, 8, and 10. ARM processors are bringing bit twiddling back into >>>> style.
Dang, I forgot about base 2!
There are 10 kinds of people:
those who understand binary and those who don't.
10 ???
c186282 <c186282@nnada.net> wrote:
On 6/21/25 7:57 PM, Charlie Gibbs wrote:
On 2025-06-21, Chris Ahlstrom <OFeem1987@teleworm.us> wrote:
rbowman wrote this post while blinking in Morse code:
On Fri, 20 Jun 2025 08:36:57 -0400, Chris Ahlstrom wrote:
Programmers use base-16.
And 2, 8, and 10. ARM processors are bringing bit twiddling back into >>>>> style.
Dang, I forgot about base 2!
There are 10 kinds of people:
those who understand binary and those who don't.
10 ???
10 -- binary for "two".
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