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"pfjw@aol.com" <pfjw@aol.com>: Apr 01 12:08PM -0700 On Saturday, April 1, 2017 at 12:02:43 PM UTC-4, Michael Terrell wrote:     > The tools to pick up SMD components use vacuum. Both manual, and > Pick-N-Place machines.   Not all of them.   http://hackaday.com/2011/02/24/magnetic-smd-pick-and-place/     Peter Wieck Melrose Park, PA

John Larkin <jjlarkin@highlandtechnology.com>: Apr 01 09:11AM -0700 On Sat, 1 Apr 2017 11:22:41 -0400, Phil Hobbs >conducting medium (the solar wind).   >Cheers   >Phil Hobbs   Is the solar wind neutral? Spacecraft typically charge a bit negative. Seems to me that the sun could be a giant thermionic cathode.   The electric field near the ground is big, around 150 volts/meter, positive going up.   http://www.feynmanlectures.caltech.edu/II_09.html     --   John Larkin Highland Technology, Inc   lunatic fringe electronics

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Apr 01 12:16PM -0400 On 04/01/2017 12:11 PM, John Larkin wrote:   > The electric field near the ground is big, around 150 volts/meter, > positive going up.   > http://www.feynmanlectures.caltech.edu/II_09.html   Yup--thunderstorms pump charge in that direction, but once you get to the top of the atmosphere the net enclosed charge is near zero.   The solar wind has to be neutral on average, because otherwise the voltage on the Sun would increase indefinitely.   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics   160 North State Road #203 Briarcliff Manor NY 10510   hobbs at electrooptical dot net http://electrooptical.net

MJC <gravity@mjcoon.plus.com>: Apr 01 05:24PM +0100 In article <TtqdndisPIn-T0LFnZ2dnUU7-SGdnZ2d@supernews.com>, pcdhSpamMeSenseless@electrooptical.net says...   > The solar wind has to be neutral on average, because otherwise the > voltage on the Sun would increase indefinitely.   What do you think causes Coronal Mass Ejections? (Whether premature or not...)   Mike.

John Larkin <jjlarkin@highlandtechnology.com>: Apr 01 09:30AM -0700 On Sat, 1 Apr 2017 12:16:35 -0400, Phil Hobbs >the top of the atmosphere the net enclosed charge is near zero.   >The solar wind has to be neutral on average, because otherwise the >voltage on the Sun would increase indefinitely.   Over tens of billions of years average. Maybe all those electrons will gradually return when the sun cools off.   If earth has a net charge, it is probably not many volts. Aren't cosmic rays almost all positive?   Most of the earth's surface is conductive, but dry sand might be a good enough insulator to have local surface potentials. Sounds like a good science project. Maybe make a drone that could scan a region and map gradients.           --   John Larkin Highland Technology, Inc   lunatic fringe electronics

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Apr 01 12:33PM -0400 On 04/01/2017 12:24 PM, MJC wrote:   > What do you think causes Coronal Mass Ejections? (Whether premature or > not...)   > Mike.   Because the body of the Sun is a good conductor, the magnetic field gets frozen in--it can change only by diffusion, which is very slow on long length scales. (It slows down quadratically with distance.)   The Sun also doesn't rotate like a rigid body--the equator rotates faster than the poles, which kinks up the field. That does work on the magnetic field, just the way an electric generator works. The resulting local increases in B eventually causes the magnetic force to overcome gravity in "reconnection events" where the kinks unkink themselves by tossing huge chunks of solar material into space.   It's sort of a magnetic version of a watch spring buckling sideways when you tighten it past a certain point with the cover off.   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics   160 North State Road #203 Briarcliff Manor NY 10510   hobbs at electrooptical dot net http://electrooptical.net

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Apr 01 12:52PM -0400 On 04/01/2017 12:30 PM, John Larkin wrote: >> voltage on the Sun would increase indefinitely.   > Over tens of billions of years average. Maybe all those electrons will > gradually return when the sun cools off.   The self-capacitance of the Sun isn't very large--its radius is about 700,000 km. The Gaussian unit of capacitance is the centimetre (which is close to a picofarad), and the self-capacitance of a sphere equals its radius in centimetres.   Thus the capacitance of the Sun is about 7E10 cm, or 0.08 F.   Wiki says that the number of particles ejected by the Sun is about 1.3E36 per second, which is about 2E17 coulombs/s, counting both positive and negative, and ignoring alpha particles having a charge of +2.   The maximum energy of the ejected particles is around 10 keV, so if the Sun's voltage with respect to the rest of the universe reached +- 10 kV, one sign of free particle would be unable to escape.   With 10**17 amps worth of the other polarity continuing to stream out, and only 80 mF of capacitance, this would be corrected in about 10**-18 seconds. ;)     > If earth has a net charge, it is probably not many volts. Aren't > cosmic rays almost all positive?   I don't know about the ones outside the atmosphere. The positive ones are much more massive than electrons, and so have more momentum per unit energy, which helps them penetrate the atmosphere.   > good enough insulator to have local surface potentials. Sounds like a > good science project. Maybe make a drone that could scan a region and > map gradients.   Cheers   Phil Hobbs     -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics   160 North State Road #203 Briarcliff Manor NY 10510   hobbs at electrooptical dot net http://electrooptical.net

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Apr 01 12:57PM -0400 On 04/01/2017 12:52 PM, Phil Hobbs wrote:   > With 10**17 amps worth of the other polarity continuing to stream out, > and only 80 mF of capacitance, this would be corrected in about 10**-18 > seconds. ;)   Whoops, 10**-14 seconds. Much gentler. ;)   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics   160 North State Road #203 Briarcliff Manor NY 10510   hobbs at electrooptical dot net http://electrooptical.net

bitrex <bitrex@de.lete.earthlink.net>: Apr 01 01:08PM -0400 On 04/01/2017 11:23 AM, Tom Biasi wrote:   >> This is what happens from abuse of drugs. >> The earth now has an 8 volt potential in reference to what? > My apologies, I forgot today's date.   OWNED!!!!11111

Sjouke Burry <burrynulnulfour@ppllaanneett.nnll>: Apr 01 07:17PM +0200 > Scientists have determined that ground is no longer at ground potential. > It dont matter if you're referring to the ground for your home's cut   Happy first of April.

John Robertson <spam@flippers.com>: Apr 01 10:51AM -0700 On 2017/04/01 8:12 AM, Tom Biasi wrote: >> Reprinted from: The Electro Scientific Journal   > This is what happens from abuse of drugs. > The earth now has an 8 volt potential in reference to what?   Have you checked today's date?   John

krw@notreal.com: Apr 01 02:05PM -0400 >human and animal lives are severely affected, and our present >electronics and electrical systems will all fail.   >Reprinted from: The Electro Scientific Journal   OMG! That's worse than global warming!

Tom Biasi <tombiasi@optonline.net>: Apr 01 02:27PM -0400 On 4/1/2017 1:08 PM, bitrex wrote: >>> The earth now has an 8 volt potential in reference to what? >> My apologies, I forgot today's date.   > OWNED!!!!11111 Yep

oldschool@tubes.com: Apr 01 01:48PM -0500 On Sat, 1 Apr 2017 10:51:42 -0700, John Robertson <spam@flippers.com> wrote:   >> The earth now has an 8 volt potential in reference to what?   >Have you checked today's date?   >John   April 1 is my favorite holiday. It's all about having fun. You dont have to dress up or impress anyone, you dont have to buy gifts, decorate or cook fancy meals, you doint have to go to church, or wave a flag, and it's the only day of the year when you can say stupid shit and act really goofy and get away with it.....   Of course this article about Electrical Grounds, 'could' be true..... I wont make any comments about it till April 2.   Happy April Fools Day!     By the way, wanna get your spouse or a friend? Remove the aerator from a faucet, put some saran wrap over the faucet, then put the aerator back on. Then wrap one prong on every plug in the house with scotch tape, and dont forget my favorite. Put a screw in adaptor from light socket to outlet in place of the refrigerator light bulb. Then plug a radio into it and turn the volume up loud. !!! Then tell your spouse, friend, or parents to get you a cold beer or soda!!!

oldschool@tubes.com: Apr 01 01:50PM -0500 On Sat, 1 Apr 2017 12:16:35 -0400, Phil Hobbs   >The solar wind has to be neutral on average, because otherwise the >voltage on the Sun would increase indefinitely.   That would be useful for people who have solar panels....

oldschool@tubes.com: Apr 01 01:54PM -0500 On Sat, 01 Apr 2017 09:30:05 -0700, John Larkin >good enough insulator to have local surface potentials. Sounds like a >good science project. Maybe make a drone that could scan a region and >map gradients.   Considering this, is the sun AC or DC? Is it LED, Florescent or Incandescent? Does it contain batterier or capacitors to keep it lit? Does anyone operate a sun control panel to keep the brightness on the same level, and color? And what is the voltage, amperage and wattage of the sun?

oldschool@tubes.com: Apr 01 11:13AM -0500 >The good capacitor is not labeled like a normal cap, so I dont know what >value it is. It says K 505J 250. (I am guessing its 250 volt, but I am >clueless about the uf value).   I did figure out one thing on my own (using Google).   505J is a Japanese way of marking a cap. In this case, it's 5uf. So it's a 5uf at 250V cap. I can only guess the "J" means Japan.   Why they cant label their caps like normal people, is frustrating, but that's how they do it. Just more complication for no advantage. Kind of like metric bolts.... The SAE bolts were just fine, but they had to complicate matters and force everyone to buy and own TWO sets of tools.

MJC <gravity@mjcoon.plus.com>: Apr 01 05:26PM +0100 In article <ovjvdcdl6jfilvtv448lkhr7vfegce472u@4ax.com>, oldschool@tubes.com says... > that's how they do it. Just more complication for no advantage. Kind of > like metric bolts.... The SAE bolts were just fine, but they had to > complicate matters and force everyone to buy and own TWO sets of tools.   Only if you still cling on to your bushels and pecks...   Mike.

etpm@whidbey.com: Apr 01 09:42AM -0700 >that's how they do it. Just more complication for no advantage. Kind of >like metric bolts.... The SAE bolts were just fine, but they had to >complicate matters and force everyone to buy and own TWO sets of tools. Be careful you don't bite your tongue while it is firmly planted in your cheek. Eric

"Michael A. Terrell" <mike.terrell@earthlink.net>: Apr 01 12:41PM -0400 > I did figure out one thing on my own (using Google).   > 505J is a Japanese way of marking a cap. In this case, it's 5uf. > So it's a 5uf at 250V cap. I can only guess the "J" means Japan.     J=+/-5% tolerance.   <http://www.dummies.com/programming/electronics/capacitor-tolerance-code/>       > Why they can't label their caps like normal people, is frustrating, but > that's how they do it. Just more complication for no advantage.     That is a standard marking. You need to study the basics, instead of constantly complaining.     -- Never piss off an Engineer!   They don't get mad.   They don't get even.   They go for over unity! ;-)

Fred McKenzie <fmmck@aol.com>: Apr 01 12:45PM -0400 In article <favudct9q3bedocjnhtvmkadilpfg2e0ks@4ax.com>, > line (only one one end of the bulbs). I was kind of thinking of > converting the fixture to LED anyhow, so now I have more reason to do > so.   Oldschool-   You caught my interest, since I have been slowly changing some old fluorescent fixtures for LED.   I'm thinking your capacitor may use a standard method of marking: significant digits 5 and 0 followed by 5 zeros, and a J to indicate 5 percent. This is in picofarads, so the result would be 5 microfarads. I agree that the 250 would be voltage. I would expect such a capacitor to be non-polarized.   I once found a similar fixture, but the two sides were just independent. Each had an inductor for ballast, but used a starter for each. I think yours may be the modern equivalent that does not use a starter.   My thought would be to replace the entire fixture, not just convert it. The cost may be similar, but the result may look and work better.   Fred

oldschool@tubes.com: Apr 01 01:33PM -0500 >My thought would be to replace the entire fixture, not just convert it. >The cost may be similar, but the result may look and work better.   >Fred   Your right about those caps. Funny thing, I began working on electronics around 1965. I have never seen a cap marked like that till now. All I have seen all those years were either marked uf, MFD, uuf MMFD, or PF. And some of them real old ones with colored bands and dots that make them look like a domino.   Yep, both sides are independent on this fixture. I think those 5uf caps replaced the starter.   I looked at the cost of a new fixture. The LED ones complete with bulbs are around $60. I can get the bulbs for about $7.50 each. Theres no sense spending the extra $45, when this fixture is just fine. Except for the socket ends and the cord, all I am re-using is the metal/plastic shell. And since I ripped out the guts, I gave it a good hose cleaning and it looks almost like new.   Besides that, I think the NEW fixtures are all plastic. I like metal better.

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Apr 01 12:11PM -0400 On 03/31/2017 02:04 PM, John Robertson wrote: > to use a Pace or similar desoldering tool that allows you to move the > leg around while you are sucking the solder out.   > John :-#)#   Good idea.   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics   160 North State Road #203 Briarcliff Manor NY 10510   hobbs at electrooptical dot net http://electrooptical.net

Jeff Liebermann <jeffl@cruzio.com>: Apr 01 09:37AM -0700 >The board I am replacing has only 6 EPROMs but still looks similar.   >Thanks for mentioning picture taking, I will for sure be doing that. I >didn't know the programmers were so inexpensive now.   This is the one that I use: <http://www.ebay.com/itm/291531758605> $30 plus $10 shipping. Maybe add about $15 for a 9V power supply, DB25 extension cable, and USB cable.   There is a later version that runs on a USB port: <http://www.ebay.com/itm/290924359652> $50 plus $14 shipping.   Notice that it uses a parallel port computah interface. Don't bother trying a USB to parallel adapter cable. It won't work. Don't use a ribbon cable for a DB25 extension. Mine went intermittent from bouncing around in my car. I wasted a few days finding the problem.   >Since I have lots >of old EPROMs from a few other FANUC controls I am gonna order a >reader/programmer and see if I can copy the junk ones.   The hard part is getting the jumpers and switches correct. Don't guess. One wrong switch or jumper and your device is blown. Also, pay attention the EPROM manufacturer. Even though the chip number might be similar, each mfg has a different voltage, timing, and programming algorithm.   You'll also need an EPROM eraser. I suggest you get one with a drawer that can handle more than one EPROM at a time. The UV light does not last very long. If you're erasing one at a time, you'll burn out the light after about 500 erases. <https://www.google.com/search?q=eprom+eraser&tbm=isch> <http://www.ebay.com/sch/i.html?_nkw=eprom+eraser> The really cheap ones are fine and all the mechanical timers are noisy and obnoxious.     -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

"Michael A. Terrell" <mike.terrell@earthlink.net>: Apr 01 12:19PM -0400 > with that computer. It's called RESERVE POWER. Under normal use, it > only uses 54W, but add a few drives and run it real hard, and the > power use demand rises.     It's called 'Not using under rated parts'. That 100W was marginal, at best when the computer was built. That 350W rating may, or may not be the real power it can deliver.     -- Never piss off an Engineer!   They don't get mad.   They don't get even.   They go for over unity! ;-)

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