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Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
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#242
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Don Lancaster has written many articles for electronics magazines. Also
regular columns for several electronics magazines (probably still running). One of his books (CMOS cookbook) was a standard for many years. You might be able to learn something from him too. Bud-- John Larkin wrote: On Tue, 14 Jun 2005 00:41:47 -0700, Don Bowey wrote: He [Don Lancaster] has tutorials? You've got to be kidding. John |
#243
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Sam Goldwasser wrote:
John Popelish writes: John Fields wrote: BTW, from another thread and just as an aside, I went over to my friend's sign shop and checked some known-good neon sign transformers using the same meters I used to check the ones I have here, and it turns out my transformers are defective. :-( Sorry to hear that. I was surprised that I couldn't simply Google this. But the elusive neon sign transformer voltage current curve remains uncaptured. No curve but some info: http://repairfaq.ece.drexel.edu/sam/...lp.htm#clpnstc Thanks, but this info is more confusing than clarifying. The table of data at reduced voltage looks pretty linear, and if the normal operating curve is not based on any nonlinear elements, then this should extrapolate to something pretty close to the actual curve. Table excerpted: " Regulation - Between an open and a short circuit, the core and winding construction results in a quasi-constant current characteristic over much of this range. I did a test on a 12 kV, 30 mA transformer at reduced voltage (I didn't have any way of providing a variable load at full output so I used a Variac to set the no load output voltage to 1,000 VAC): Load Output Voltage Output Current ------------------------------------------- Open 1,000 VAC 0.00 mA R 560 VAC 1.43 mA R/2 350 VAC 1.79 mA R/3 250 VAC 1.91 mA R/4 195 VAC 1.99 mA R/5 160 VAC 2.04 mA Short 0 VAC 2.10 mA" But a few paragraphs later we read: "(From: John De Armond ).) Let me answer several questions at once. First, a 15 kV, 60 mA transformer will produce 60 ma almost up to its rated voltage. The transformer is designed to be a constant current device, to supply whatever compliance voltage is needed to push the 60 ma through the load. The 60 ma is nominal short-circuit. All magnetic transformers made for use in the US are designed for continuous use at no more than 80% of the short-circuit current. I never actually sat down and plotted it out but I do know this: With 1 foot of neon tubing on a transformer (about 500 volt drop), it drives 60 mA. With over 60 feet of tubing on the tranny (more than specified), it still outputs about 50 to 53 mA. That's fairly constant current." But 80% of short circuit current would be 48 mA, and the current did not fall that far, even with an excessive 60 feet of tubing as a load. So the various parts of this story do not add up. The low voltage test indicates linearity, while the full voltage test indicates current regulation. The specified operating current does not match the measured current. So I am still confused. |
#244
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On Wed, 15 Jun 2005 05:44:34 -0700, Kitchen Man wrote:
On Wed, 15 Jun 2005 03:36:15 -0500, John Fields wrote: It is my belief that the widespread disagreement is due to participants that just like to argue a lot. --- No, they don't. ;^) Look, this isn't an argument, it's just contradiction! No, it's not! ;^j -- The Pig Bladder from Uranus, still waiting for that hot babe to ask what my favorite planet is... |
#245
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On Wed, 15 Jun 2005 12:32:21 +0000, Kevin Aylward wrote:
John Fields wrote: .... But when a self-important know-nothing windbag like you comes along making baseless proclamations and spouting opinions like they were gospel it _does_ annoy me. Er..the gospels are the biggest pile of erroneous nonsense one can come up with. Its all about those imaginary beings, that can do anything, be everywhere at once, knows everything etc... Hey! Let's not knock the imaginary! Where would electronics be today without sqrt(-1)? ;-) -- Rich for further information, please visit http://www.godchannel.com |
#246
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On Wed, 15 Jun 2005 09:23:39 -0500, Bud
wrote: Don Lancaster has written many articles for electronics magazines. Also regular columns for several electronics magazines (probably still running). One of his books (CMOS cookbook) was a standard for many years. You might be able to learn something from him too. Bud-- John Larkin wrote: On Tue, 14 Jun 2005 00:41:47 -0700, Don Bowey wrote: He [Don Lancaster] has tutorials? You've got to be kidding. John Oh no, I thought someone was referring to The Phantom's tutorials. Don always makes eminent sense. I have his Active Filter Cookbook right here. John |
#247
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On 6/15/05 7:23 AM, in article ,
"Bud" wrote: Don Lancaster has written many articles for electronics magazines. Also regular columns for several electronics magazines (probably still running). One of his books (CMOS cookbook) was a standard for many years. You might be able to learn something from him too. Bud-- John Larkin wrote: On Tue, 14 Jun 2005 00:41:47 -0700, Don Bowey wrote: He [Don Lancaster] has tutorials? You've got to be kidding. John The quoted posts were not as you have posted them. They did not include the "[Don Lancaster)." Shame on you, Bud. Don |
#248
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On Wed, 15 Jun 2005 14:48:44 GMT, Pig Bladder
wrote: On Wed, 15 Jun 2005 05:44:34 -0700, Kitchen Man wrote: On Wed, 15 Jun 2005 03:36:15 -0500, John Fields wrote: It is my belief that the widespread disagreement is due to participants that just like to argue a lot. --- No, they don't. ;^) Look, this isn't an argument, it's just contradiction! No, it's not! ;^j --- Yes, it is!^) -- John Fields Professional Circuit Designer |
#249
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#250
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Don Bowey wrote:
On 6/15/05 7:23 AM, in article , "Bud" wrote: Don Lancaster has written many articles for electronics magazines. Also regular columns for several electronics magazines (probably still running). One of his books (CMOS cookbook) was a standard for many years. You might be able to learn something from him too. Bud-- John Larkin wrote: On Tue, 14 Jun 2005 00:41:47 -0700, Don Bowey wrote: He [Don Lancaster] has tutorials? You've got to be kidding. John The quoted posts were not as you have posted them. They did not include the "[Don Lancaster)." Shame on you, Bud. The standard English syntax for inserting edited text into a quote, usually to show meaning that deleted context made clear, is to enclose it between said square brackets. Which is to say that, while not commonly used on Usenet, Bud's quote is proper style. If you read newspapers or news magazines you will see it used often. -- Floyd L. Davidson http://web.newsguy.com/floyd_davidson Ukpeagvik (Barrow, Alaska) |
#251
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Quotes in this post have been edited by application of
the DERF transform, whereby Dreck, Extraneousness, Redundancy, and Foolishness are replaced with "[DERF]". "Fred Bloggs" wrote in message ... Larry Brasfield wrote: "Fred Bloggs" wrote in message ... Larry Brasfield wrote: "John Fields" wrote in message ... Since this a technical forum and we _do_ have ground rules, I believe we generally agree that, unless otherwise specified, standard pressure is defined as 760 millimeters of mercury and standard temperature is defined as zero degrees celcius. I believe that in this forum we assume temperature is a variable that must be accommodated in design, unless otherwise stated. I cannot imagine why any unstated temperature would be assumed to be 0 oC. I suppose sea-level atmospheric pressure is often assumed, but where it matters, it should not be assumed at all. While the boiling point of water is dependent on pressure, the freezing point, I believe, is not. You might want to consider the "triple point" of water, below which pressure "melting point" is meaningless and the "freezing point" varies considerably with pressure. At least, not to a great extent. I don't have any data to support that position, but I'd love to see some, if it's out there. See: http://www.lsbu.ac.uk/water/phase.html Using the usual meaning of "freezing" which is the transition from liquid to solid, that graph shows "freezing" occurring at 273K over a million to one range in pressure. It does not. The straight part of the liquid/solid phase boundary covers less than 5 orders of magnitude. "Over a million to one" would be more than 6 orders of magnitude. Bull- it goes from 10^3 to 10^9 Pa, idiot. You have now demonstrated yourself to be either an idiot, blind, or a liar. Not does the straight portion of that curve fail to reach 10^9 Pa, no part of it reaches that pressure. I would say that the statement "While the boiling point of water is dependent on pressure, the freezing point, I believe, is not" is essentially true In a discussion that has involved sublimation, to exclude that part of the phase space would be essentially silly. There is no discussion- Actually, John's post to which I first responded in this thread, mentioned "sublimation". So, again, ignoring that whole phase change boundary would be silly. the statement was about water "freezing", The conversion of water vapor into ice is "freezing". You cannot, by assertion and fiat, eliminate that part of water's phase space. In your typically parochial manner, you appear to confuse your familiarity with one meaning of the word with comphrehensive knowledge. Anybody less certain that they know everything can find several additional meanings, including my usage, at: http://www.m-w.com/cgi-bin/dictionar...reeze&x=14&y=9 [DERF] Have you ever considered why you are so prone to spewing so much self-revealing vitriol? -- --Larry Brasfield email: Above views may belong only to me. |
#252
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John Fields wrote:
On Wed, 15 Jun 2005 01:49:34 -0800, (Floyd L. Davidson) wrote: John Fields wrote: --- Not at all. I'm always grateful when someone takes the time to correct me and show me where I went wrong, since that increases my store of stuff I know is right. John, you can't have it both ways. You say the above is what you do, but what you actually *do* is the next paragraph: --- IKYABWAI? Come on Floyd, you can do better than that. Or can you? --- But when a self-important know-nothing windbag like you comes along making baseless proclamations and spouting opinions like they were gospel it _does_ annoy me. John Fields Professional Circuit Designer ^^^^^^^^^^^^ When will that begin? Yeah, that's clever; attack the dotsig. In an effort to find out a little more about you, I checked Google's archives and here's one interesting article posted a year or so ago which I found right away: BEGIN QUOTE (Eugene Miya) wrote: In article , Jim Roberts wrote: I've never met Floyd, though I'd like to. He thinks he knows a lot more than he really does. He used to harrass me. I checked out some his most aggressive assertions that I wasn't completely sure about with aurhorities, and he came up pretty dry. Yet, he's likely to be an interesting person, so long as you don't listen to him too attentively. END QUOTE So, it seems, a leopard can't change his spots... What did Eugene have to say? And tell me, do you know who Jim Roberts and Eugene Miya are? If we have you using Roberts as a supporting witness, and Eugene (yes Eugene and I have met) as mine... you do realize that you're off the deep end again? (Roberts is somewhat of a net loon. Eugene Miya is a net legend.) You've proven that you aren't the first twit that I've poked enough to cause erruption of tantrums. You can't say I didn't warn you not to try a flame war... -- Floyd L. Davidson http://web.newsguy.com/floyd_davidson Ukpeagvik (Barrow, Alaska) |
#253
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Rich The Philosophizer wrote:
On Wed, 15 Jun 2005 12:32:21 +0000, Kevin Aylward wrote: John Fields wrote: ... But when a self-important know-nothing windbag like you comes along making baseless proclamations and spouting opinions like they were gospel it _does_ annoy me. Er..the gospels are the biggest pile of erroneous nonsense one can come up with. Its all about those imaginary beings, that can do anything, be everywhere at once, knows everything etc... Hey! Let's not knock the imaginary! Where would electronics be today without sqrt(-1)? ;-) sqrt(-1) is just as imaginary as 1 is. Kevin Aylward http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. |
#254
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John Fields wrote:
On Wed, 15 Jun 2005 14:48:44 GMT, Pig Bladder wrote: On Wed, 15 Jun 2005 05:44:34 -0700, Kitchen Man wrote: On Wed, 15 Jun 2005 03:36:15 -0500, John Fields wrote: It is my belief that the widespread disagreement is due to participants that just like to argue a lot. --- No, they don't. ;^) Look, this isn't an argument, it's just contradiction! No, it's not! ;^j --- Yes, it is!^) No it isnt. An argument is a connected series of statements intended to establish a proposition... next... Kevin Aylward http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. |
#255
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On Wed, 15 Jun 2005 19:09:04 GMT, "Kevin Aylward"
wrote: John Fields wrote: On Wed, 15 Jun 2005 14:48:44 GMT, Pig Bladder wrote: On Wed, 15 Jun 2005 05:44:34 -0700, Kitchen Man wrote: On Wed, 15 Jun 2005 03:36:15 -0500, John Fields wrote: It is my belief that the widespread disagreement is due to participants that just like to argue a lot. --- No, they don't. ;^) Look, this isn't an argument, it's just contradiction! No, it's not! ;^j --- Yes, it is!^) No it isnt. An argument is a connected series of statements intended to establish a proposition... next... --- I guess you missed the part about that I was disagreeing with Pig Bladder about his contention that it wasn't just contradiction. next... -- John Fields Professional Circuit Designer |
#256
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#257
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#258
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"John Fields" wrote in message
... On Wed, 15 Jun 2005 19:09:04 GMT, "Kevin Aylward" wrote: John Fields wrote: On Wed, 15 Jun 2005 14:48:44 GMT, Pig Bladder wrote: On Wed, 15 Jun 2005 05:44:34 -0700, Kitchen Man wrote: On Wed, 15 Jun 2005 03:36:15 -0500, John Fields wrote: It is my belief that the widespread disagreement is due to participants that just like to argue a lot. --- No, they don't. ;^) Look, this isn't an argument, it's just contradiction! No, it's not! ;^j --- Yes, it is!^) No it isnt. An argument is a connected series of statements intended to establish a proposition... next... --- I guess you missed the part about that I was disagreeing with Pig Bladder about his contention that it wasn't just contradiction. next... -- John Fields Professional Circuit Designer No he didn't. Ken |
#259
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"Kevin Aylward" wrote in message
. uk... John Fields wrote: On Wed, 15 Jun 2005 14:48:44 GMT, Pig Bladder wrote: On Wed, 15 Jun 2005 05:44:34 -0700, Kitchen Man wrote: On Wed, 15 Jun 2005 03:36:15 -0500, John Fields wrote: It is my belief that the widespread disagreement is due to participants that just like to argue a lot. --- No, they don't. ;^) Look, this isn't an argument, it's just contradiction! No, it's not! ;^j --- Yes, it is!^) No it isnt. An argument is a connected series of statements intended to establish a proposition... next... Kevin Aylward Sorry, your time's up....... Ken |
#260
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On Wed, 15 Jun 2005 11:00:00 -0800, Floyd L. Davidson wrote:
John Fields wrote: [some stuff] You've proven that you aren't the first twit that I've poked enough to cause erruption of tantrums. You can't say I didn't warn you not to try a flame war... Problem is, you're losing miserably... ;-P -- The Pig Bladder from Uranus |
#261
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![]() "John Fields" wrote in message ... I guess you missed the part about that I was disagreeing with Pig Bladder about his contention that it wasn't just contradiction. next... http://neptune.spaceports.com/~words/beavis.html N |
#262
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John Larkin wrote:
On Wed, 15 Jun 2005 09:30:33 -0800, (Floyd L. Davidson) wrote: John Larkin wrote: On Tue, 14 Jun 2005 00:41:47 -0700, Don Bowey wrote: He [Don Lancaster] has tutorials? You've got to be kidding. John The quoted posts were not as you have posted them. They did not include the "[Don Lancaster)." Shame on you, Bud. The standard English syntax for inserting edited text into a quote, usually to show meaning that deleted context made clear, is to enclose it between said square brackets. Nothing was deleted! So? Did anyone claim there was? Which is to say that, while not commonly used on Usenet, Bud's quote is proper style. If you read newspapers or news magazines you will see it used often. The style may be proper by your standards - certainly not mine - but Bud's useage meets widely accepted and well known English. What *you* think about it is immaterial. the [content] is dead wrong. Nowhere did I refer to Don. We were talking about The Phantom. Provide some context that demonstrates it then, because it doesn't appear to be what you are now claiming. -- Floyd L. Davidson http://web.newsguy.com/floyd_davidson Ukpeagvik (Barrow, Alaska) |
#263
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On Wed, 15 Jun 2005 13:01:02 -0800, (Floyd L.
Davidson) wrote: John Larkin wrote: On Wed, 15 Jun 2005 09:30:33 -0800, (Floyd L. Davidson) wrote: John Larkin wrote: On Tue, 14 Jun 2005 00:41:47 -0700, Don Bowey wrote: He [Don Lancaster] has tutorials? You've got to be kidding. John The quoted posts were not as you have posted them. They did not include the "[Don Lancaster)." Shame on you, Bud. The standard English syntax for inserting edited text into a quote, usually to show meaning that deleted context made clear, is to enclose it between said square brackets. Nothing was deleted! So? Did anyone claim there was? Which is to say that, while not commonly used on Usenet, Bud's quote is proper style. If you read newspapers or news magazines you will see it used often. The style may be proper by your standards - certainly not mine - but Bud's useage meets widely accepted and well known English. What *you* think about it is immaterial. the [content] is dead wrong. Nowhere did I refer to Don. We were talking about The Phantom. Provide some context that demonstrates it then, because it doesn't appear to be what you are now claiming. The only person that matters here is Don, and that he knows I didn't insult him. Get a life. John |
#264
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#266
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On Wed, 15 Jun 2005 13:01:02 -0800, (Floyd L.
Davidson) wrote: John Larkin wrote: On Wed, 15 Jun 2005 09:30:33 -0800, (Floyd L. Davidson) wrote: John Larkin wrote: On Tue, 14 Jun 2005 00:41:47 -0700, Don Bowey wrote: He [Don Lancaster] has tutorials? You've got to be kidding. John The quoted posts were not as you have posted them. They did not include the "[Don Lancaster)." Shame on you, Bud. The standard English syntax for inserting edited text into a quote, usually to show meaning that deleted context made clear, is to enclose it between said square brackets. Nothing was deleted! So? Did anyone claim there was? Which is to say that, while not commonly used on Usenet, Bud's quote is proper style. If you read newspapers or news magazines you will see it used often. The style may be proper by your standards - certainly not mine - but Bud's useage meets widely accepted and well known English. What *you* think about it is immaterial. the [content] is dead wrong. Nowhere did I refer to Don. We were talking about The Phantom. Provide some context that demonstrates it then, because it doesn't appear to be what you are now claiming. --- So, you miserable, troublemaking piece of ****, you've decided to take on John Larkin? Big mistake. There's no way you can even begin to think about getting close to his track record, let alone even get into the stadium, so why don't you just quit before you embarrass yourself by not even being able to leave the starting blocks? -- John Fields Professional Circuit Designer |
#267
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On Wed, 15 Jun 2005 18:01:25 -0500, John Fields
wrote: On Tue, 14 Jun 2005 11:21:21 -0800, (Floyd L. Davidson) wrote: The idea that water boils at 100C and freezes at 0C, without some mention of pressure, has little meaning. Water can "boil" at 0C too. --- Since, by your own admission, the boiling and freezing point temperatures of water are pressure dependent, I invite you to state what pressure would be required to be exerted on a volume of liquid water in order to cause it to boil at 0°C. The boiling and freezing points are pressure dependent. Not only that, a certain amount of heat must be lost or gained (latent heat, I believe, is the term) before the change of state occurs. I am simply going by memory of my old Physics classes, and I have no idea what pressure would be required to allow water to boil at 0 C. I think other substances have boiled at lower temperatures than that at STP though. Tom |
#268
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"Tom MacIntyre" wrote in
message ... On Wed, 15 Jun 2005 18:01:25 -0500, John Fields wrote: On Tue, 14 Jun 2005 11:21:21 -0800, (Floyd L. Davidson) wrote: The idea that water boils at 100C and freezes at 0C, without some mention of pressure, has little meaning. Water can "boil" at 0C too. Since, by your own admission, the boiling and freezing point temperatures of water are pressure dependent, I invite you to state what pressure would be required to be exerted on a volume of liquid water in order to cause it to boil at 0°C. The boiling and freezing points are pressure dependent. Not only that, a certain amount of heat must be lost or gained (latent heat, I believe, is the term) before the change of state occurs. Strictly speaking, the change of state occurs as the latent heat is transferred, not after. I am simply going by memory of my old Physics classes, and I have no idea what pressure would be required to allow water to boil at 0 C. I think other substances have boiled at lower temperatures than that at STP though. If you peruse the phase space of water at http://www.lsbu.ac.uk/water/phase.html you will see that there is no liquid/vapor boundary at 0 oC. At a range of pressure well below standard atmospheric, it could happen near 0.01 oC. John's challenge is a bit of a trick and appears to show he knows how to read that graph and accompanying table. -- --Larry Brasfield email: Above views may belong only to me. |
#269
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On Wed, 15 Jun 2005 18:01:25 -0500, the renowned John Fields
wrote: On Tue, 14 Jun 2005 11:21:21 -0800, (Floyd L. Davidson) wrote: The idea that water boils at 100C and freezes at 0C, without some mention of pressure, has little meaning. Water can "boil" at 0C too. --- Since, by your own admission, the boiling and freezing point temperatures of water are pressure dependent, I invite you to state what pressure would be required to be exerted on a volume of liquid water in order to cause it to boil at 0°C. Good one, John! Best regards, Spehro Pefhany -- "it's the network..." "The Journey is the reward" Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com |
#270
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On Wed, 15 Jun 2005 23:37:49 GMT, Tom MacIntyre
wrote: On Wed, 15 Jun 2005 18:01:25 -0500, John Fields wrote: On Tue, 14 Jun 2005 11:21:21 -0800, (Floyd L. Davidson) wrote: The idea that water boils at 100C and freezes at 0C, without some mention of pressure, has little meaning. Water can "boil" at 0C too. --- Since, by your own admission, the boiling and freezing point temperatures of water are pressure dependent, I invite you to state what pressure would be required to be exerted on a volume of liquid water in order to cause it to boil at 0°C. The boiling and freezing points are pressure dependent. Not only that, a certain amount of heat must be lost or gained (latent heat, I believe, is the term) before the change of state occurs. --- At one atmosphere of pressure, the "latent heat of vaporization" of water is 540 calories per gram and is the amount of heat required to change liquid water at 100°C into steam at 100°C. That's used to great advantage, in reverse, in steam heating systems where steam which has been generated in a boiler is forced to condense into liquid water in a remotely located radiator and release that heat into the environment surrounding the radiator when it (the steam) changes state. --- I am simply going by memory of my old Physics classes, and I have no idea what pressure would be required to allow water to boil at 0 C. I think other substances have boiled at lower temperatures than that at STP though. --- Yes. Liquefied gases, in particular, do that, and I'm anxiously awaiting Floyd Davidson's response which will nail down the pressure required to allow water to boil at 0°C. -- John Fields Professional Circuit Designer |
#271
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#272
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On Wed, 15 Jun 2005 19:52:15 -0400, Spehro Pefhany
wrote: Good one, John! --- :-) -- John |
#273
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"Larry Brasfield" wrote:
"Tom MacIntyre" wrote in message ... On Wed, 15 Jun 2005 18:01:25 -0500, John Fields wrote: On Tue, 14 Jun 2005 11:21:21 -0800, (Floyd L. Davidson) wrote: The idea that water boils at 100C and freezes at 0C, without some mention of pressure, has little meaning. Water can "boil" at 0C too. Since, by your own admission, the boiling and freezing point temperatures of water are pressure dependent, I invite you to state what pressure would be required to be exerted on a volume of liquid water in order to cause it to boil at 0°C. The boiling and freezing points are pressure dependent. Not only that, a certain amount of heat must be lost or gained (latent heat, I believe, is the term) before the change of state occurs. Strictly speaking, the change of state occurs as the latent heat is transferred, not after. I am simply going by memory of my old Physics classes, and I have no idea what pressure would be required to allow water to boil at 0 C. I think other substances have boiled at lower temperatures than that at STP though. If you peruse the phase space of water at http://www.lsbu.ac.uk/water/phase.html you will see that there is no liquid/vapor boundary at 0 oC. At a range of pressure well below standard atmospheric, it could happen near 0.01 oC. John's challenge is a bit of a trick and appears to show he knows how to read that graph and accompanying table. Are you saying that it could happen at 0.01C but not at 0.00C, because you see something in that chart which says water is liquid at 0.01C and not at 0.00C? I don't see that in the chart at all. The chart does not have sufficient resolution. It doesn't discuss that in the text either. Did you mean something else? -- Floyd L. Davidson http://web.newsguy.com/floyd_davidson Ukpeagvik (Barrow, Alaska) |
#274
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John Fields wrote:
On Tue, 14 Jun 2005 11:21:21 -0800, (Floyd L. Davidson) wrote: The idea that water boils at 100C and freezes at 0C, without some mention of pressure, has little meaning. Water can "boil" at 0C too. --- Since, by your own admission, the boiling and freezing point temperatures of water are pressure dependent, I invite you to state what pressure would be required to be exerted on a volume of liquid water in order to cause it to boil at 0°C. The answer of course is: not much. -- Floyd L. Davidson http://web.newsguy.com/floyd_davidson Ukpeagvik (Barrow, Alaska) |
#275
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Rich The Philosophizer wrote:
Er..the gospels are the biggest pile of erroneous nonsense one can come up with. Its all about those imaginary beings, that can do anything, be everywhere at once, knows everything etc... Hey! Let's not knock the imaginary! Where would electronics be today without sqrt(-1)? ;-) Up the paddle without a creek? ;-} Ed |
#276
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On Wed, 15 Jun 2005 19:35:17 -0500, John Fields wrote:
On Wed, 15 Jun 2005 23:37:49 GMT, Tom MacIntyre The boiling and freezing points are pressure dependent. Not only that, a certain amount of heat must be lost or gained (latent heat, I believe, is the term) before the change of state occurs. At one atmosphere of pressure, the "latent heat of vaporization" of water is 540 calories per gram and is the amount of heat required to change liquid water at 100°C into steam at 100°C. That's used to great advantage, in reverse, in steam heating systems where steam which has been generated in a boiler is forced to condense into liquid water in a remotely located radiator and release that heat into the environment surrounding the radiator when it (the steam) changes state. Well, it takes one calorie per gram to raise liquid water one degree centigrade - I wonder if, at an ambient pressure of, say, 10^3 Pa, it still takes 540 calories per gram to transform a gram of liquid water at 0degC to a gram of gaseous steam at 0degC. I am simply going by memory of my old Physics classes, and I have no idea what pressure would be required to allow water to boil at 0 C. I think other substances have boiled at lower temperatures than that at STP though. Yes. Liquefied gases, in particular, do that, and I'm anxiously awaiting Floyd Davidson's response which will nail down the pressure required to allow water to boil at 0°C. According to the graph at http://www.lsbu.ac.uk/water/phase.html , approx. 10^3 Pa, whatever the hell that means. Obviously, an atmosphere is up there near the "annoying point", ;-) , between 10^8 and 10^9 Pa. Hope This Helps! :-) Rich |
#277
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On Wed, 15 Jun 2005 19:52:15 -0400, Spehro Pefhany wrote:
On Wed, 15 Jun 2005 18:01:25 -0500, the renowned John Fields wrote: On Tue, 14 Jun 2005 11:21:21 -0800, (Floyd L. Davidson) wrote: The idea that water boils at 100C and freezes at 0C, without some mention of pressure, has little meaning. Water can "boil" at 0C too. --- Since, by your own admission, the boiling and freezing point temperatures of water are pressure dependent, I invite you to state what pressure would be required to be exerted on a volume of liquid water in order to cause it to boil at 0°C. Good one, John! Best regards, Spehro Pefhany Lame. Approx. 10^3 Pa. http://www.lsbu.ac.uk/water/phase.html ;^j -- The Pig Bladder from Uranus, still waiting for that hot babe to ask what my favorite planet is! ;-J |
#278
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On Thu, 16 Jun 2005 01:54:45 +0000, ehsjr wrote:
Rich The Philosophizer wrote: Er..the gospels are the biggest pile of erroneous nonsense one can come up with. Its all about those imaginary beings, that can do anything, be everywhere at once, knows everything etc... Hey! Let's not knock the imaginary! Where would electronics be today without sqrt(-1)? ;-) Up the paddle without a creek? ;-} From "Channeling Class": "...You will know how to interpret the information in my energy because it will show up as a pattern in your imagination. "Channeling, like all other inner phenomena happens in the imagination. This is the faculty humans use to access the inner planes, spiritual worlds, divine reality or whatever you wish to call what is beyond the external, material world. We'll make use of the imagination to establish contact with each other, and to carry out the channeling process. You can think of the imagination as a permeable membrane located right at the water line in the metaphor of the iceberg in the introduction to this class. Being between the two major parts of the mind, it is shared by both. "New ideas, insights, creative inspiration and intuition all begin in the unconscious mind. As these kinds of impressions, including the energy you will be interpreting, rise to awareness, they pass through the imagination. The conscious, aware mind perceives these impressions as representations in the imagination. Sometimes the impressions are represented visually as images or pictures, sometimes auditorily as sounds or words, and sometimes sensorially as feelings or energy." -- http://www.godchannel.com/chanclass1.html So, don't knock the imagination. ;-D -- Love, Rich for further information, please visit http://www.godchannel.com |
#279
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On Thu, 16 Jun 2005 01:54:45 +0000, ehsjr wrote:
Rich The Philosophizer wrote: [in response to someone else whom ehsjr has failed to attribute] Er..the gospels are the biggest pile of erroneous nonsense one can come up with. Its all about those imaginary beings, that can do anything, be everywhere at once, knows everything etc... Hey! Let's not knock the imaginary! Where would electronics be today without sqrt(-1)? ;-) Up the paddle without a creek? ;-} That's another interesting question - is there really a "hole" in the donut, or are you buying a hole, with donut around it? The hole was there first, you know. ;-p -- Cheers! Rich ------ "A nubile female virtually never experiences difficulty in finding willing sexual partners, and in a natural habitat nubile females are probably always married. The basic female "strategy" is to obtain the best possible husband, to be fertilized by the fittest available male (always, of course, taking risk into account), and to maximize the returns on sexual favors bestowed: to be sexually aroused by the sight of males would promote random matings, thus undermining all of these aims, and would also waste time and energy that could be spent in economically significant activities and in nurturing children. A female's reproductive success would be seriously compromised by the propensity to be sexually aroused by the sight of males." -- Donald Symons, "The Evolution of Human Sexuality", attempting to explain the lack of female interest in pornography. [And you wondered why "Diamonds are a girl's best friend?"] |
#280
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On Thu, 16 Jun 2005 02:55:51 GMT, the renowned Pig Bladder
wrote: On Wed, 15 Jun 2005 19:52:15 -0400, Spehro Pefhany wrote: On Wed, 15 Jun 2005 18:01:25 -0500, the renowned John Fields wrote: On Tue, 14 Jun 2005 11:21:21 -0800, (Floyd L. Davidson) wrote: The idea that water boils at 100C and freezes at 0C, without some mention of pressure, has little meaning. Water can "boil" at 0C too. --- Since, by your own admission, the boiling and freezing point temperatures of water are pressure dependent, I invite you to state what pressure would be required to be exerted on a volume of liquid water in order to cause it to boil at 0°C. Good one, John! Best regards, Spehro Pefhany Lame. Approx. 10^3 Pa. http://www.lsbu.ac.uk/water/phase.html ;^j Do you happen to know what the triple-point of water is? Best regards, Spehro Pefhany -- "it's the network..." "The Journey is the reward" Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com |
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