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rickman <gnuarm@gmail.com>: Aug 31 10:00PM -0400 Someone was talking about decimal time where the second is shortened by about 15% allowing 100 secs/minute, 100 minutes/hr, 10 hr/day.   I think the utility of this is limited and it would cause a lot of changes in society. We presently have a large number of convenient time increments which would not be so convenient in the new system.   First, the hour would be 2.4 times longer leaving us with no convenient unit about the same length of time as the hour. The closest would be the quad-deci-hour which would be 0.96 old hours. The deci-hour would be pretty convenient about 4% shorter than a quarter hour. The old half hour would now be about a fifth of a new hour, so we could call it a "fifth" which might become confused with a non-metric liquor measure, a fifth of a gallon which has since become 750 ml in metric.   The inconvenience would come from the need to totally recalibrate every type of measurement we use that considers time... speed limits, work days, time zones... Would we extend this change to measurements of angles which often are done in degrees, minutes, seconds?   How would we adjust the work day? Do we go to 3 hour work days which would be about 7.2 old hours? Shift work would have to split hours to get three shifts while some businesses that use two 12 old hour shifts would hum along just fine with 5 new hour shifts. Many businesses opening at 9 AM would now open at 4:00 (I assume we would just count 0 to 9 hours rather than the annoying AM/PM thing), folks would take a lunch break at 5:00 and banks would close around 6:00 while retail would remain open until 9:00 or 9:50 (hmmm, that is still about the same).   The minutes gets pretty whacked gaining 26.4 old seconds. So "give me a minute" becomes a quarter more weighty of a request. The original pulse was conceived to match the human pulse so our normal pulse rate will become 86 bpm instead of 60 bpm.   In science the changes would be enormous. With a redefinition of the second every time related measurement would have to change including many in EE such as capacitance/charge/current, heck, the definition of the gravitational constant and even the speed of light would have to change. Every text book would change and every instrument. This would create so much confusion that we really would need new names for the second, minute and hour.   This could go on all day (the one measurement that doesn't change) with a huge list of changes we will have to make and the many adaptations we as a society would need to accommodate. Then, in the end, we would still have leap years.   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

Tom Biasi <tombiasi@optonline.net>: Aug 31 10:16PM -0400 On 8/31/2017 10:00 PM, rickman wrote: > a huge list of changes we will have to make and the many adaptations we > as a society would need to accommodate.  Then, in the end, we would > still have leap years.   Anyone old enough may remember when the USA tried to go metric. The people just would not go for it and it was abandoned.

rickman <gnuarm@gmail.com>: Aug 31 10:36PM -0400 Tom Biasi wrote on 8/31/2017 10:16 PM: >> leap years.   > Anyone old enough may remember when the USA tried to go metric. The people > just would not go for it and it was abandoned.   I don't remember that "people just would not go for it". I don't recall much resistance at all. I think the "resistance" was at other levels. We had a partnership with Canada to change together and had a multi-step program. We completed the first two or three steps and quit. That's why metric is taught today in schools, it was part of step two or three. When we had to take a step that would actually change something (I think it was highway signs) we told Canada to go on without us and we'd catch up later... *much* later.   I can't believe that even today we still use English units in many engineering fields. Mechanical engineers often use inches and feet. God knows what civil engineers use, probably rods. It was just recently that I learned the acre comes from 160 square rods.   Actually I just looked it up and the acre was defined as 1 chain by 1 furlong while a rod is a quarter of a chain. A chain is 0.1 furlong, so they are all a related system of measurement.   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

Tom Biasi <tombiasi@optonline.net>: Aug 31 11:13PM -0400 On 8/31/2017 10:36 PM, rickman wrote:   > Actually I just looked it up and the acre was defined as 1 chain by 1 > furlong while a rod is a quarter of a chain.  A chain is 0.1 furlong, so > they are all a related system of measurement.   Well you and I remember differently. I was involved in the teaching of the metric system to the people of the USA. There was great resistance and money for the project soon got thin. When I studied engineering in the 70's we used the metric system exclusively. We didn't call it SI, it was just the way the scientific community did it.

rickman <gnuarm@gmail.com>: Sep 01 03:57AM -0400 Tom Biasi wrote on 8/31/2017 11:13 PM: > for the project soon got thin. When I studied engineering in the 70's we > used the metric system exclusively. We didn't call it SI, it was just the > way the scientific community did it.   What teaching were you involved in? I assume it was companies asking you to educate employees? That is not related to the government. It also has nothing to do with the "resistance" from the average person. No one was overly enthusiastic about it since it was a big change, but people were willing to go with the flow. Mostly they just didn't understand it as there had been only notification that it would happen and the education was only in the schools. I believe it was industry that resisted the change much to our detriment over the decades.   I don't know what you mean about metric not being "SI". I didn't know diddly about metric until I was in college (before the conversion program started) and was taught the SI system. I believe prior to SI there was a metric system that had a few units that were different from today's SI by some powers of 10. CGS and dynes come to mind.   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

Look165 <look165@numericable.fr>: Sep 01 10:28AM +0200 It is worthless.   The animal bodies are regulated by the 24h system.   And it would be necessary to redefine the reference second which is now related to the cesiuaam atom.It is the international reference like the meter also related to this atom       rickman a écrit :

"pfjw@aol.com" <pfjw@aol.com>: Sep 01 04:08AM -0700 Mpffffff... what is unique about time-keeping as-practiced? It is base-12. Meaning that its 24-hour days are nicely divisible by more prime numbers than if it were base-10. It also goes nicely with 360 degrees, and such. It is something that entire world agrees to - one of the very few things.   Esperanto, anyone?   Peter Wieck Melrose Park, PA

ABLE1 <someone@nowhere.net>: Sep 01 08:02AM -0400 On 8/31/2017 10:00 PM, rickman wrote: > a huge list of changes we will have to make and the many adaptations we > as a society would need to accommodate.  Then, in the end, we would > still have leap years.   If I may interject: A lot of years ago I was at a party. I was with a small group of people and I brought up the topic of Metric Time. I said it as if I really knew about it and that it was reported on the nightly news by Tom Brokaw the night before. I said the certain part of Canada had all ready switched over.   I said it as a joke but did not say that it was. Everyone was 'oh and 'aw about it and swallowed hook, line and sinker. I walked away from the group and moved else were, snickering all the way.   About 15 minutes later, I got a tap on the shoulder. I turned and faced a guy that was in that previous group. He had a serious look of embarrassment and irritation. He said "Metric Time?? Really??" I just smiled and said "Got Cha". And we had a good laugh.   Actually still laughing today. Since this post put me back to the a very funny moment in time.   Thanks for the memories.   Les

Tim R <timothy42b@aol.com>: Sep 01 05:55AM -0700 During the time of the pyramids and pharaohs, the Egyptian calendar had 5 days "out of time" at the beginning of the year, then 12 months of 30 days each.   That still makes more sense than what we do now.

Taxed and Spent <nospamplease@nonospam.com>: Sep 01 06:07AM -0700 On 9/1/2017 5:55 AM, Tim R wrote: > During the time of the pyramids and pharaohs, the Egyptian calendar had 5 days "out of time" at the beginning of the year, then 12 months of 30 days each.   > That still makes more sense than what we do now.   If we did that now, the politicians will call those tax-free days, with the remainder being taxed at 100%.

"pfjw@aol.com" <pfjw@aol.com>: Sep 01 06:28AM -0700 > If we did that now, the politicians will call those tax-free days, with > the remainder being taxed at 100%.   Something like the 0 and 00 on American Roulette wheels?   Keep in mind that the 'modern' calendar was the creation of a religious institution to keep the calendar from 'slipping' and entirely for religious purposes. Islam uses a lunar calendar and slips by about 10 days each year. This is most significant during Ramadan, when fasting is from sunrise to sunset. Makes things a bit hard the further north (or south) one goes when Ramadan falls in the local summer time. But, several other groups, including Buddhists and others use calendars apart from the Gregorian calendar - no surprise there at all.   Peter Wieck Melrose Park, PA

jethro tull <heavytull@outlook.com>: Sep 01 10:45AM I noticed that since renesas overtook nec some references have changed. I'm searching for the 2SD2403 which can be with GX, GY, or GZ marking on the chip but nowadays I'm mostly finding 2SD2403-AZ, 2SD2403T1-AZ, and 2SD2403T2-AZ. And when downloading the datasheet on renesas website I always get a copy of the nec datasheet with an added disclaimer preface from renesas. But there are no reference to the new ref. code. So if someone knows more about this?

Tim Schwartz <tim@bristolnj.com>: Sep 01 08:25AM -0400 On 9/1/2017 6:45 AM, jethro tull wrote: > when downloading the datasheet on renesas website I always get a copy of the > nec datasheet with an added disclaimer preface from renesas. But there are no > reference to the new ref. code. So if someone knows more about this?   Hello,   I don't really know NEC numbering, but could the new suffix's indicate a different package, like surface mount instead of through hole? The GX,GY or GZ rating is a beta range on the transistor. See:   http://pdf1.alldatasheet.com/datasheet-pdf/view/112254/NEC/2SD2403.html   on page 2 of the PDF.   Also, sometimes the suffix can tell how things are shipped or packaged, like on a tape reel for auto insertion, or loose, or in a tube.   Regards, Tim

N_Cook <diverse@tcp.co.uk>: Sep 01 08:49AM +0100 So not directly over tidal water , viewing horizontally the rise and fall of tidal water over mud flats. There is a change in light level , excluding fog, between veiwing the mud and veiwing the water. Night time there is a lot of street-light spill over , if moonless. Perhaps a web-cam , with masked off view of a vertical slot with range of angle from about -2 degrees to the horizontal , to about -50 deg, with no boats, reed-beds or anything else in the view, just mud or water. I assume it would be possible to digitally determine the "terminator" as it moves up and down and initially generate a look-up table comparing to a proper tide-gauge nearby, for the heights corresponding to the image. Any other ideas?

Andy Burns <usenet@andyburns.uk>: Sep 01 09:40AM +0100 N_Cook wrote:   > Any other ideas?   Rotate a polarising filter in front of the camera, look for differences in the light reflected by water and mud?

N_Cook <diverse@tcp.co.uk>: Sep 01 12:42PM +0100 On 01/09/2017 09:40, Andy Burns wrote:   >> Any other ideas?   > Rotate a polarising filter in front of the camera, look for differences > in the light reflected by water and mud?   Thats an interesting idea, but would that be sunlight only and rather variable angle during the day? I'm thinking of that early Viking navigation instrument of 2 slabs of felspar on a viewing tube, to know the time, by rotating one wrt the other.

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Sep 01 01:07PM +1000 On 1/09/2017 11:29 AM, rickman wrote:   >> BTW: The "metric part of the world" is 95% of the world. A pitifully >> insignificant 5% holds out against the inevitable.   > You talkin' 'bout US?     **Yup. Just a few weeks back, I had to work on a US built product. Damned thing had two different types of Allen bolts in it (Whitworth and SAE). None of my usual Imperial Allen keys would fit it. I had to grind an old key down to fit. I NEVER have such issues with products using Metric Allen bolts. And, let's not get started with those insane fractional sizes, for screws, drills and all the other stuff. Metris stuff is so much easier. 1mm, 1.5mm, 2mm, 2.5mm, 3mm and so on. It just makes sense.   I guess you can thank your brain-damaged Prez (at the time - Reagan) for that stupidity. Come to think of it, you have another brain-damaged Prez running the show again. What gives with you guys? You seem to vote for people with the intellect of a 10 year old every now and again.     -- Trevor Wilson www.rageaudio.com.au

rickman <gnuarm@gmail.com>: Sep 01 03:50AM -0400 Trevor Wilson wrote on 8/31/2017 11:07 PM: > And, let's not get started with those insane fractional sizes, for screws, > drills and all the other stuff. Metris stuff is so much easier. 1mm, 1.5mm, > 2mm, 2.5mm, 3mm and so on. It just makes sense.   What are you talking about Whitworth??? Nobody uses Whitworth in the US. That's a British thing.   Actually it's a bit funny that you are bringing up the fractions. The sizes you mention are only convenient because of chance. Metric sizes are often very inconvenient. Feet and inches are very handy for most things we deal with because they were invented with convenience in mind. Metric is great when you are working with the numbers, but often the actual sizes are much less than convenient. Six foot skis are very convenient, but 180 cm are not so much. Another example, PCB traces are still measured in thousandths of an inch even when working with metric sized boards because the numbers are much more convenient, i.e. 6/6 vs. 0.1524 mm.   Yeah, I'm for converting, but it's not about convenience of units, it's about being able to do calculations more easily.   Hell, the metric stuff has mucked up measuring devices even when they aren't metric. I've never seen a tape measure with binary based fractions written in decimal numbers until now. That is the most useless thing yet!     > that stupidity. Come to think of it, you have another brain-damaged Prez > running the show again. What gives with you guys? You seem to vote for > people with the intellect of a 10 year old every now and again.   Seems to me electing bad leaders is not unique to the US. Which country are you from? Never had any bad leaders, huh?   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Sep 01 08:26PM +1000 On 1/09/2017 5:50 PM, rickman wrote: >> 2mm, 2.5mm, 3mm and so on. It just makes sense.   > What are you talking about Whitworth???  Nobody uses Whitworth in the > US. That's a British thing.   **Truthfully, I have no idea what the other Allen bolts were. My SAE Allen keys fitted one set, but none of the SAE ones I had (or the ones my neighbour had) fitted. Maybe it wasn't Whitworth, but it sure wasn't Metric or SAE.     > Actually it's a bit funny that you are bringing up the fractions.  The > sizes you mention are only convenient because of chance.  Metric sizes > are often very inconvenient.   **Nope. Never. However, I'll bite: When do you think they're inconvenient?     Feet and inches are very handy for most > things we deal with because they were invented with convenience in > mind.   **12 inches = 1 foot. 3 feet = 1 yard. 1,760 feet = 1 mile. In what universe is this convenient? Western numbering is base 10. Not base 12. It's fucking insane.     Metric is great when you are working with the numbers, but often > the actual sizes are much less than convenient.  Six foot skis are very > convenient, but 180 cm are not so much.   **Since my skis are 2 Metres, I find them quite convenient. Yeah, I know, I really should buy some of those modern skis.       Another example, PCB traces are > still measured in thousandths of an inch even when working with metric > sized boards because the numbers are much more convenient, i.e. 6/6 vs. > 0.1524 mm.   **On that we agree. The electronics industry is likely stuck with such arcane measurements for a very long time.     > Yeah, I'm for converting, but it's not about convenience of units, it's > about being able to do calculations more easily.   **Yep. Base 10. Not base 12, or whatever silly measurements the Imperial system deems appropriate. 16 ounces = 1 pound. Sheesh! How many pints in a gallon? How many in a US gallon? It goes on and on, with sillier units.   > aren't metric.  I've never seen a tape measure with binary based > fractions written in decimal numbers until now.  That is the most > useless thing yet!   **Huh? Most of my tape measures are printed in Metric and Imperial. The Metric side is easier to use and read. FWIW: I grew up with Imperial. Switching to Metric was painless and delightful.   >> people with the intellect of a 10 year old every now and again.   > Seems to me electing bad leaders is not unique to the US.  Which country > are you from?  Never had any bad leaders, huh?   **Australia and, yes. We've had a few, but none quite as appalling as Trump.     -- Trevor Wilson www.rageaudio.com.au

Boris Mohar <borism_void_@sympatico.ca>: Sep 01 07:31AM -0400 >I was having this discussion with a few people and no one knew the >answer..... >(Personally, I think they would still be 45 rpm, but I could be wrong).   282.743339999999 radians per minute.       Regards,   Boris Mohar   Got Knock? - see: Viatrack Printed Circuit Designs (among other things) http://www.viatrack.ca   void _-void-_ in the obvious place     --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Andy Burns <usenet@andyburns.uk>: Sep 01 12:37PM +0100 > If we were using a metric system at that time, would they still be > called 45 rpm, or would there be some metric numbers used instead?   0.75 Hz

"~misfit~" <shaun.at.pukekohe@gmail.com>: Sep 01 08:22AM +1200 Once upon a time on usenet Bob Engelhardt wrote: > convenient for cutting into pieces, but nice for cutting shapes to a > template, or for finishing edges that have been cut with too much > chipping.   I worked in a high-end cabinet making workshop and have used a free-hand spindle moulder before for cutting acrylic for kitchen drawer fronts etc. Just fix it to a (thick wooden) template (for the bearing to run on) with double sided tape and Bob's your uncle.   A small spindle moulder can be made using a decent router. -- Shaun.   "Humans will have advanced a long, long way when religious belief has a cozy little classification in the DSM*." David Melville (in r.a.s.f1) (*Diagnostic and Statistical Manual of Mental Disorders)

Ancel B <protofabtt@gmail.com>: Aug 31 07:33PM -0700 Hi Dave: Laser machining is the precision way to go.   If you require a steady supply I might be able to help out as I am making some custom plexi bezels and lexan implosion shields for vintage O'scopes and automobile dashboard fascia (flexible 0.35mm & 0.50mm thick material) right now.   I have 1mm, 3mm & 6mm clear plexi on hand as well as 0.35mm and 0.50mm EVA material.   If you need custom color 'gel' film filters bonded to the EVA I have a process developed for that as well.   Ancel     On Wednesday, August 30, 2017 at 6:57:16 PM UTC-4, Dave M wrote:

oldschool@tubes.com: Aug 31 12:32AM -0400 On Wed, 30 Aug 2017 17:57:06 -0500, "Dave M" <dgminala@mediacombb.net> wrote:   >bit dangerous due to the small size of the work. Clamping would be tricky.   >Any suggestions as to a good, safe approach to cutting the plastic?   >Dave M   When a hardware store cuts plexiglass for a storm door or window, they put the sheet in a glass cutting frame. That is nothing more than a rack with a straight edge and a lever to apply pressure against the part you want cut. Then they use a special cutter made for plexiglass, which is really just a sharp blade. They score it with that cutter from top to bottom. Then they use that lever to apply pressure and SNAP, they make a nice clean cut.   I was in a place where I had to cut some myself. I did not have that special cutter or a rack. I marked it with a sharpie. Then I took a straight piece of aluminum, laid it on my mark, and scored it with a utility knife with a new blade. Once it was scored, I placed the scored line along the edge of a board and applied pressure with my hand. That worked fine.   One thing I learned, never try to drill plexiglass. You will end up with small cracks around the hole. I once wanted to put some hinges onto plexiglass and learned the hard way about the cracks. Then I used a soldering iron and melted holes. It was kind of messy, sicne the melted plastic builds up around the hole and needs to be quickly removed while it's still hot and soft, but that did work in the end. (The soldering iron tip was pretty much trash though, I ssaved it for future plexiglass holes, but would never try to solder with it).

Phil Allison <pallison49@gmail.com>: Sep 01 01:56AM -0700 Michael Terrell wrote:   ------------------------     > Think again. You have a negative and a positive peak, not just a > single peak. You have to add them together.   ** Nonsense, the DC rating is not exceeded by a reversing voltage.     > That is why the original DC cap was 600V, not 300V.     ** False.   It's simply that 600V rated caps survive much better.   AC supply and load bridging involves spike voltages that can break down the insulation.       ..... Phil

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