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Posted: 5/5/2015 12:15:46 AM EDT
[#1]
If I were a betting man, I'd bet against it.
I do hope they're onto something! Our galaxy is so large, we really need something completely different than what we have right now. Even ion thrusters do not give us a high enough speed and there are issues about fueling them and powering them once you get away from the sun. |
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Posted: 5/5/2015 12:24:31 AM EDT
[#2]
I'm waiting for the Alcubierre-White drive!
 Now... just to find something to generate the mass-energy of Jupiter |
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Posted: 5/5/2015 10:00:44 AM EDT
[#3]
Quote HistoryQuoted:
I'm waiting for the Alcubierre-White drive!
Now... just to find something to generate the mass-energy of Jupiter That's one of the stranger bits- they've measured some kind of path length expansion inside the resonant chamber during operation, and one that's significantly larger than that predicted by thermal effects. The implication is that space itself is expanding inside the chamber. That may be a stretch, and I would wave this kind of thing away without a second thought normally, but NASA JSC isn't exactly banging rocks together. http://www.nasaspaceflight.com/2015/04/evaluating-nasas-futuristic-em-drive/ |
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Posted: 5/5/2015 1:40:18 PM EDT
[#4]
I bet that there is a rational explanation that fits within the known laws of physics and the scientists working on this project having been smart enough to figure it out yet. I hope I am wrong and this is going to lead to some new and exciting developments.
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Posted: 5/5/2015 5:44:20 PM EDT
[#5]
Watching with a skeptical, but very interested, eye.
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Posted: 5/5/2015 7:09:40 PM EDT
[#6]
I think it took about 2 years to prove cold fusion was a fraud. Well, maybe fraud is not the right word,... was not a net energy producer.
Heck, I'd be happy to have a practical, economical HOT fusion reactor. or any other sort of practical, economically-sound source of energy that cuts the cord to the middle east oil. |
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Posted: 5/6/2015 4:47:17 PM EDT
[#7]
Quote HistoryQuoted:
I think it took about 2 years to prove cold fusion was a fraud. Well, maybe fraud is not the right word,... was not a net energy producer. Heck, I'd be happy to have a practical, economical HOT fusion reactor. or any other sort of practical, economically-sound source of energy that cuts the cord to the middle east oil. We already drilled our way out of that problem. |
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Posted: 5/6/2015 11:41:18 PM EDT
[#8]
Quote HistoryQuoted:
I think it took about 2 years to prove cold fusion was a fraud. Well, maybe fraud is not the right word,... was not a net energy producer. Heck, I'd be happy to have a practical, economical HOT fusion reactor. or any other sort of practical, economically-sound source of energy that cuts the cord to the middle east oil. My understanding is that bog-standard nuclear power could already meet the expectations of our expanding energy needs for the next 400 years, using just domestic ore sources. It really depends on fostering an effective regulatory environment, which is to say, one that ensures compliance with best-practice safety procedures while not being so byzantine and capricious that it makes the economics infeasible. That, and getting NIMBYs under control. |
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Posted: 5/7/2015 1:43:10 AM EDT
[#9]
Problem with fossil fuels: pollution and anthropogenic climate change.
Problem with nuclear: waste disposal especially with the current stalemate over Yucca Mountain Complex. Bonus for Fusion reactor: radioactive waste would have a MUCH shorter half-life than fission waste. Progress with 'hot' fusion: energy gain documented by national ignition laboratory.**** **** highly qualified statement. The fuel capsule released more energy than was input. HOWEVER, the total amount of energy required to generate that confined beam that resulted in the 'input energy' is still MUCH greater than what was output. |
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Posted: 5/8/2015 3:25:15 PM EDT
[#10]
Problem with nuclear: waste disposal Only because the public is so ignorant and fearful of the 'radiation' word. Things with very large half lives are rarely all that dangerous. There are not enough particles coming off to be a real issue. Things with shorter half lives (30 days, 90 days, even tens of years in significant quantities) MAY be a hazard depending on WHAT they are throwing off. Cobalt 60 with a ~5.7 year half life and energetic (betas and gammas with a couple of MeVs of energy) can easily produce a decent dose at close range. Time, distance, rate, and of course particle type. While electrons are often rather harmless (they cannot penetrate much) if the energy is high enough they can start to be a problem. I spent years doing radiation testing of materials and electronics for satellite use. Protons in the magnetic belts cannot be effectively shielded and at the wrong place in orbit can have 500 MeV of energy and tens of thousands per square centimeter per second. They also 'activate' targets something fiercely. The iron in Kovar (lead material on packages) and even copper and lead can leave some rather 'hot' residuals. We used to walk up to targets with a Geiger counter. If it got high at 10 feet you waited 10 minutes and tried again. Sometimes we had to wait an hour or so to have the cool enough to quickly pick up and put behind some lead bricks. |
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Posted: 5/8/2015 3:27:33 PM EDT
[#11]
Quote HistoryQuoted: I think it took about 2 years to prove cold fusion was a fraud. Well, maybe fraud is not the right word,... was not a net energy producer. Heck, I'd be happy to have a practical, economical HOT fusion reactor. or any other sort of practical, economically-sound source of energy that cuts the cord to the middle east oil. We've been "50 years away" from viable commercial fusion for what, 60 years now? |
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Posted: 5/8/2015 3:29:25 PM EDT
[#12]
Quote HistoryQuoted: Only because the public is so ignorant and fearful of the 'radiation' word. Things with very large half lives are rarely all that dangerous. There are not enough particles coming off to be a real issue. Things with shorter half lives (30 days, 90 days, even tens of years in significant quantities) MAY be a hazard depending on WHAT they are throwing off. Cobalt 60 with a ~5.7 year half life and energetic (betas and gammas with a couple of MeVs of energy) can easily produce a decent dose at close range. Time, distance, rate, and of course particle type. While electrons are often rather harmless (they cannot penetrate much) if the energy is high enough they can start to be a problem. I spent years doing radiation testing of materials and electronics for satellite use. Protons in the magnetic belts cannot be effectively shielded and at the wrong place in orbit can have 500 MeV of energy and tens of thousands per square centimeter per second. They also 'activate' targets something fiercely. The iron in Kovar (lead material on packages) and even copper and lead can leave some rather 'hot' residuals. We used to walk up to targets with a Geiger counter. If it got high at 10 feet you waited 10 minutes and tried again. Sometimes we had to wait an hour or so to have the cool enough to quickly pick up and put behind some lead bricks. Quote HistoryQuoted: Problem with nuclear: waste disposal Only because the public is so ignorant and fearful of the 'radiation' word. Things with very large half lives are rarely all that dangerous. There are not enough particles coming off to be a real issue. Things with shorter half lives (30 days, 90 days, even tens of years in significant quantities) MAY be a hazard depending on WHAT they are throwing off. Cobalt 60 with a ~5.7 year half life and energetic (betas and gammas with a couple of MeVs of energy) can easily produce a decent dose at close range. Time, distance, rate, and of course particle type. While electrons are often rather harmless (they cannot penetrate much) if the energy is high enough they can start to be a problem. I spent years doing radiation testing of materials and electronics for satellite use. Protons in the magnetic belts cannot be effectively shielded and at the wrong place in orbit can have 500 MeV of energy and tens of thousands per square centimeter per second. They also 'activate' targets something fiercely. The iron in Kovar (lead material on packages) and even copper and lead can leave some rather 'hot' residuals. We used to walk up to targets with a Geiger counter. If it got high at 10 feet you waited 10 minutes and tried again. Sometimes we had to wait an hour or so to have the cool enough to quickly pick up and put behind some lead bricks. See also, spent fuel reprocessing. Fuck you, Jimmy Carter!  |
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Posted: 5/9/2015 12:37:58 AM EDT
[#13]
yes, i completely agree, with the proper shielding, nuclear waste isn't a big issue.
However, you still have to designate a long term storage solution. What we have right now is not a good plan. Yucca was the solution. But too many people bought in to the "no nuclear waste going through my backyard mentality" |
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Posted: 5/9/2015 7:53:34 AM EDT
[#14]
Quote HistoryQuoted:
I think it took about 2 years to prove cold fusion was a fraud. Well, maybe fraud is not the right word,... was not a net energy producer. Heck, I'd be happy to have a practical, economical HOT fusion reactor. or any other sort of practical, economically-sound source of energy that cuts the cord to the middle east oil. My understanding is that cold fusion IS a net energy producer, just in very, very small amounts. And that the researchers can't explain where the energy comes from except as a byproduct of the cold fusion. |
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Posted: 5/9/2015 1:52:10 PM EDT
[#15]
Quote HistoryQuoted: My understanding is that cold fusion IS a net energy producer, just in very, very small amounts. And that the researchers can't explain where the energy comes from except as a byproduct of the cold fusion. Quote HistoryQuoted: Quoted: I think it took about 2 years to prove cold fusion was a fraud. Well, maybe fraud is not the right word,... was not a net energy producer. Heck, I'd be happy to have a practical, economical HOT fusion reactor. or any other sort of practical, economically-sound source of energy that cuts the cord to the middle east oil. My understanding is that cold fusion IS a net energy producer, just in very, very small amounts. And that the researchers can't explain where the energy comes from except as a byproduct of the cold fusion. |
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Posted: 5/16/2015 1:55:26 PM EDT
[#16]
However, you still have to designate a long term storage solution. The long tem part is rarely the problem. Long half lives indicate SLOW decay rates. U235 is around 7E8 years. 700 million years. You are perfectly safe handling and touching it. It is a nasty heavy metal poison if ingested. Pu2389 is 24,110 years. Again, safe to handle. We used latex gloves for either. We also used latex for heavy ion exposure for satellite testing of electronics and material. Check with a Geiger counter to see if it has become activated (not common with heavy ion testing). The gloves are to make sure nothing on the surface of the target stays on your skin. Strip them off (technique matters) and dispose of as 'low level' waste in the marked can. The speed of light produces a mathematical singularity (square root -1 or a divide by zero problem) in our models. We need another model but have yet to find one. So far Einstein has been scary accurate. To the absolute limits of what is even possible to measure (see Heisenberg uncertainty). For many years in communications and electrical engineering we used a simple thermal model for possible noise limits. We have a fancier one now called the Cramer-Rao bound that is based on Heisenberg. |
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Posted: 5/17/2015 1:09:43 AM EDT
[#17]
Quote HistoryQuoted:
It is a net energy producer, we just have problems producing it on a scale that is useful. We either get tiny reactions that are more or less only good for research or we get a thermonuclear weapon. Getting something in between is proving tricky. Quote HistoryQuoted:
Quoted:
Quoted:
I think it took about 2 years to prove cold fusion was a fraud. Well, maybe fraud is not the right word,... was not a net energy producer. Heck, I'd be happy to have a practical, economical HOT fusion reactor. or any other sort of practical, economically-sound source of energy that cuts the cord to the middle east oil. My understanding is that cold fusion IS a net energy producer, just in very, very small amounts. And that the researchers can't explain where the energy comes from except as a byproduct of the cold fusion. Do you remember the original claims being made,... the funding given to cold fusion companies who have still not delivered? Do you remember the inability of so many labs to reproduce the results consistent with the original claims? Is cold fusion the viable, utility-grade energy source as was originally claimed or is it some quantum-scale laboratory curiosity (if that)? |
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Posted: 5/17/2015 3:09:51 PM EDT
[#18]
Quote HistoryQuoted: Do you remember the original claims being made,... the funding given to cold fusion companies who have still not delivered? Do you remember the inability of so many labs to reproduce the results consistent with the original claims? Is cold fusion the viable, utility-grade energy source as was originally claimed or is it some quantum-scale laboratory curiosity (if that)? Quote HistoryQuoted: Quoted: Quoted: My understanding is that cold fusion IS a net energy producer, just in very, very small amounts. And that the researchers can't explain where the energy comes from except as a byproduct of the cold fusion. Do you remember the original claims being made,... the funding given to cold fusion companies who have still not delivered? Do you remember the inability of so many labs to reproduce the results consistent with the original claims? Is cold fusion the viable, utility-grade energy source as was originally claimed or is it some quantum-scale laboratory curiosity (if that)? |
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Posted: 5/17/2015 3:11:41 PM EDT
[#19]
Quote HistoryQuoted:
We've been "50 years away" from viable commercial fusion for what, 60 years now? Quote HistoryQuoted:
Quoted:
I think it took about 2 years to prove cold fusion was a fraud. Well, maybe fraud is not the right word,... was not a net energy producer. Heck, I'd be happy to have a practical, economical HOT fusion reactor. or any other sort of practical, economically-sound source of energy that cuts the cord to the middle east oil. We've been "50 years away" from viable commercial fusion for what, 60 years now? Locheed-Martin is saying less than ten now. |
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Posted: 5/18/2015 1:42:50 AM EDT
[#20]
Just so we are clear on this, I have to say, I hope they are, all of them, correct about their observations of previously unseen natural processes and engineering advances in the direction of viable system.
Really, I hope they all succeed, whether it is 10 years away or 20. |
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Posted: 5/18/2015 11:48:36 PM EDT
[#21]
Back on the EM drive, an interesting characteristic is that the engine is a closed cavity, there is no "open end". You could actually bury it inside the middle of a spacecraft.
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Posted: 5/18/2015 11:54:41 PM EDT
[#22]
Also, just found this. I'm not convinced that the guy isn't just seeing some magnetic field interaction (he needs to do an inverted test), but it is VERY interesting if a duct tape and baling wire version such as this actually produces measurable thrust.
https://www.youtube.com/watch?v=Rbf7735o3hQ |
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Posted: 7/27/2015 9:28:24 PM EDT
[#23]
Update on this one from Dresden University of Technology:
http://science.slashdot.org/story/15/07/27/2016209/german-scientists-confirm-nasas-controversial-em-drive |
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Posted: 7/30/2015 10:20:54 AM EDT
[#24]
I want to believe.
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Posted: 8/4/2015 9:19:34 PM EDT
[#25]
Quote HistoryQuoted:
Also, just found this. I'm not convinced that the guy isn't just seeing some magnetic field interaction (he needs to do an inverted test), but it is VERY interesting if a duct tape and baling wire version such as this actually produces measurable thrust. https://www.youtube.com/watch?v=Rbf7735o3hQ He does need to do an inverted test and change the environment to better isolate the drive from EMI that could be coming from the power supply. I am not convinced he has true thrust yet but there is something going on there. It is just such a sloppy set up that it is hard to tell what he is getting. |
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Posted: 8/11/2015 12:04:41 PM EDT
[#26]
Testibng such things can be extremely difficult.
I have a nice globe on my desk that spins inside a plastic enclosure. It is perfectly weighted to flat in the liquid between the globe and the enclosure. It is powered by a solar cell that is used to drive an electromagnet. The electromagnet reacts against the earth's magnetic field to slowly rotate the globe. As long as their is enough light making it through the globe printing it rotates. Nothing inside is actually visible besides the printed paper on the inner globe. http://www.movaglobestore.com/ One of Murphy's laws is "Any sufficiently advanced technology is indistinguishable from magic." A magnetic field in a closed container (like the walls of a resonant cavity) could easily react with an external filed. You should have seen our high current cables jump when energized. Their magnetic field produces force agasint the earth's field. Ever seen power line jump after a large fault? Same thing. |
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Posted: 9/19/2015 2:32:32 AM EDT
[#27]
Quote HistoryQuoted:
Testibng such things can be extremely difficult. I have a nice globe on my desk that spins inside a plastic enclosure. It is perfectly weighted to flat in the liquid between the globe and the enclosure. It is powered by a solar cell that is used to drive an electromagnet. The electromagnet reacts against the earth's magnetic field to slowly rotate the globe. As long as their is enough light making it through the globe printing it rotates. Nothing inside is actually visible besides the printed paper on the inner globe. http://www.movaglobestore.com/ One of Murphy's laws is "Any sufficiently advanced technology is indistinguishable from magic." A magnetic field in a closed container (like the walls of a resonant cavity) could easily react with an external filed. You should have seen our high current cables jump when energized. Their magnetic field produces force agasint the earth's field. Ever seen power line jump after a large fault? Same thing. The energy in the power line is not enclosed inside a wave guide. In the EM drive, all the EM energy is confined inside the conical wave guide, well the operators had better they are sealed or they are getting a nice dose of RF energy. Assuming they are not microwaving themselves, then 99% + of the EM energy is confined and not interacting with an external field. I work with and test RF wave guides on semi-conductor equipment that uses MW of RF energy. |
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Posted: 9/22/2015 5:21:42 PM EDT
[#28]
Problem with fossil fuels: pollution and anthropogenic climate change. Problem with nuclear: waste disposal especially with the current stalemate over Yucca Mountain Complex. Nuclear waste disposal is a political problem, not a physical one. I read many years ago, and I think it’s true, that the easiest and safest disposal sites are depleted oil wells. Texas and Oklahoma are covered with them. The oil was down there for millions of years and it didn’t contaminate anything. Just dump the waste in several of them. Of course, we might find a significant use for that stuff someday. It would be a shame if we couldn’t get to it! |
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Posted: 9/24/2015 3:58:36 PM EDT
[#29]
Quote HistoryQuoted:
The energy in the power line is not enclosed inside a wave guide. In the EM drive, all the EM energy is confined inside the conical wave guide, well the operators had better they are sealed or they are getting a nice dose of RF energy. Assuming they are not microwaving themselves, then 99% + of the EM energy is confined and not interacting with an external field. I work with and test RF wave guides on semi-conductor equipment that uses MW of RF energy. Quote HistoryQuoted:
Quoted:
Testibng such things can be extremely difficult. I have a nice globe on my desk that spins inside a plastic enclosure. It is perfectly weighted to flat in the liquid between the globe and the enclosure. It is powered by a solar cell that is used to drive an electromagnet. The electromagnet reacts against the earth's magnetic field to slowly rotate the globe. As long as their is enough light making it through the globe printing it rotates. Nothing inside is actually visible besides the printed paper on the inner globe. http://www.movaglobestore.com/ One of Murphy's laws is "Any sufficiently advanced technology is indistinguishable from magic." A magnetic field in a closed container (like the walls of a resonant cavity) could easily react with an external filed. You should have seen our high current cables jump when energized. Their magnetic field produces force agasint the earth's field. Ever seen power line jump after a large fault? Same thing. The energy in the power line is not enclosed inside a wave guide. In the EM drive, all the EM energy is confined inside the conical wave guide, well the operators had better they are sealed or they are getting a nice dose of RF energy. Assuming they are not microwaving themselves, then 99% + of the EM energy is confined and not interacting with an external field. I work with and test RF wave guides on semi-conductor equipment that uses MW of RF energy. The energy in the power line actually travels in the electric and magnetic field around the line. By controlling for the spacing and total current in the line (it must sum to zero, charge cannot 'accumulate') A group of cables IS a 'wave guide' even at 60 Hz. Start approaching 1/4 wave (3E8/60 meters) and BAD things happen with switching and loads. |
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Posted: 9/25/2015 1:48:58 AM EDT
[#30]
Quote HistoryQuoted:
The energy in the power line actually travels in the electric and magnetic field around the line. By controlling for the spacing and total current in the line (it must sum to zero, charge cannot 'accumulate') A group of cables IS a 'wave guide' even at 60 Hz. Start approaching 1/4 wave (3E8/60 meters) and BAD things happen with switching and loads. Quote HistoryQuoted:
Quoted:
Quoted:
Testibng such things can be extremely difficult. I have a nice globe on my desk that spins inside a plastic enclosure. It is perfectly weighted to flat in the liquid between the globe and the enclosure. It is powered by a solar cell that is used to drive an electromagnet. The electromagnet reacts against the earth's magnetic field to slowly rotate the globe. As long as their is enough light making it through the globe printing it rotates. Nothing inside is actually visible besides the printed paper on the inner globe. http://www.movaglobestore.com/ One of Murphy's laws is "Any sufficiently advanced technology is indistinguishable from magic." A magnetic field in a closed container (like the walls of a resonant cavity) could easily react with an external filed. You should have seen our high current cables jump when energized. Their magnetic field produces force agasint the earth's field. Ever seen power line jump after a large fault? Same thing. The energy in the power line is not enclosed inside a wave guide. In the EM drive, all the EM energy is confined inside the conical wave guide, well the operators had better they are sealed or they are getting a nice dose of RF energy. Assuming they are not microwaving themselves, then 99% + of the EM energy is confined and not interacting with an external field. I work with and test RF wave guides on semi-conductor equipment that uses MW of RF energy. The energy in the power line actually travels in the electric and magnetic field around the line. By controlling for the spacing and total current in the line (it must sum to zero, charge cannot 'accumulate') A group of cables IS a 'wave guide' even at 60 Hz. Start approaching 1/4 wave (3E8/60 meters) and BAD things happen with switching and loads. My point is the in a EM drive, the EM-field is completely enclosed, shielding it from the earths EM field, hence there would be no interaction. |
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Posted: 11/6/2015 10:54:25 AM EDT
[#31]
Supposedly, they've reduced some potential measurement errors...still measuring thrust.
http://www.dailymail.co.uk/sciencetech/article-3305990/Nasa-conducts-secret-tests-impossible-engine-Study-reveals-fuel-free-thrusters-work-no-one-knows-why.html |
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Posted: 11/6/2015 1:27:29 PM EDT
[#32]
Quote HistoryQuoted:
My point is the in a EM drive, the EM-field is completely enclosed, shielding it from the earths EM field, hence there would be no interaction. Quote HistoryQuoted:
Quoted:
Quoted:
Quoted:
Testibng such things can be extremely difficult. I have a nice globe on my desk that spins inside a plastic enclosure. It is perfectly weighted to flat in the liquid between the globe and the enclosure. It is powered by a solar cell that is used to drive an electromagnet. The electromagnet reacts against the earth's magnetic field to slowly rotate the globe. As long as their is enough light making it through the globe printing it rotates. Nothing inside is actually visible besides the printed paper on the inner globe. http://www.movaglobestore.com/ One of Murphy's laws is "Any sufficiently advanced technology is indistinguishable from magic." A magnetic field in a closed container (like the walls of a resonant cavity) could easily react with an external filed. You should have seen our high current cables jump when energized. Their magnetic field produces force agasint the earth's field. Ever seen power line jump after a large fault? Same thing. The energy in the power line is not enclosed inside a wave guide. In the EM drive, all the EM energy is confined inside the conical wave guide, well the operators had better they are sealed or they are getting a nice dose of RF energy. Assuming they are not microwaving themselves, then 99% + of the EM energy is confined and not interacting with an external field. I work with and test RF wave guides on semi-conductor equipment that uses MW of RF energy. The energy in the power line actually travels in the electric and magnetic field around the line. By controlling for the spacing and total current in the line (it must sum to zero, charge cannot 'accumulate') A group of cables IS a 'wave guide' even at 60 Hz. Start approaching 1/4 wave (3E8/60 meters) and BAD things happen with switching and loads. My point is the in a EM drive, the EM-field is completely enclosed, shielding it from the earths EM field, hence there would be no interaction. The magnetic portion of the field cannot be "completely enclosed." |
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Posted: 11/7/2015 12:09:13 AM EDT
[#33]
Quote HistoryQuoted:
The magnetic portion of the field cannot be "completely enclosed." Quote HistoryQuoted:
Quoted:
Quoted:
Quoted:
Quoted:
Testibng such things can be extremely difficult. I have a nice globe on my desk that spins inside a plastic enclosure. It is perfectly weighted to flat in the liquid between the globe and the enclosure. It is powered by a solar cell that is used to drive an electromagnet. The electromagnet reacts against the earth's magnetic field to slowly rotate the globe. As long as their is enough light making it through the globe printing it rotates. Nothing inside is actually visible besides the printed paper on the inner globe. http://www.movaglobestore.com/ One of Murphy's laws is "Any sufficiently advanced technology is indistinguishable from magic." A magnetic field in a closed container (like the walls of a resonant cavity) could easily react with an external filed. You should have seen our high current cables jump when energized. Their magnetic field produces force agasint the earth's field. Ever seen power line jump after a large fault? Same thing. The energy in the power line is not enclosed inside a wave guide. In the EM drive, all the EM energy is confined inside the conical wave guide, well the operators had better they are sealed or they are getting a nice dose of RF energy. Assuming they are not microwaving themselves, then 99% + of the EM energy is confined and not interacting with an external field. I work with and test RF wave guides on semi-conductor equipment that uses MW of RF energy. The energy in the power line actually travels in the electric and magnetic field around the line. By controlling for the spacing and total current in the line (it must sum to zero, charge cannot 'accumulate') A group of cables IS a 'wave guide' even at 60 Hz. Start approaching 1/4 wave (3E8/60 meters) and BAD things happen with switching and loads. My point is the in a EM drive, the EM-field is completely enclosed, shielding it from the earths EM field, hence there would be no interaction. The magnetic portion of the field cannot be "completely enclosed." You can reduce reduce the influence of the Earth's magnetic field by using something like a properly designed mu-metal enclosure, or a succession of them. Pretty good way to isolate static magnetic fields. |
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Posted: 11/7/2015 12:47:33 PM EDT
[#34]
Mu-metal is a PITA to use.
Simply forming it degrades the effectiveness unless followed by high temperature annealing. We used it to protect very sensitive sensors from street trolley fields. You form slide together pieces with complete coverage then anneal them. Wrapping with a lot of soft iron makes a great starting point. |
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