Thanks much. I was roaming around Amazon trying to find a strong magnet to go meteorite hunting with and did not know that if I ordered an N52 that it might not be what I get. Guess I have more research to do. Thanks.
Thank you for your video, I appreciate the information. I was curious to know if these magnets would be useful in accelerating protons in a compact, or even a tabletop, linear or synchrotron accelerator, with an energy gradient of at least 25 MeV/m, in an accelerator cavity not much longer than 10 m, which would be sufficient to produce a beam of 250 MeV protons, which assuming a 1 mA beam current, would result in a 250 kW beam power. I've heard that non-superconducting magnets, the most powerful of which are N52 grade neodymium magnets, are capable of energy gradients of up to 100 MeV/m, and that only superconducting magnets can make that larger; however, I'm not really sure what the true limitations are of non-superconducting magnets, but that's what I've read.
I'd suggest lowering the energy gradient to at least 10 MeV/m to compromise for the reflection factor. This occurs in the cavity due to unstable acceleration characteristics when particle variances occur. 1mA of beem current would be safe enough if you use Dilithium crystals at your input and output ports to avoid any interactions from the cavities self oscillation reactance losses. I will contact the Star Ship Enterprise at 2200 hours and see if we can arrange a pick up date.
@@GrantsPassTVRepair Thanks, I did some research and found that using a special "hard" CuAg alloy for the RF cavity, with 0.08% silver composition, would suffice in achieving a 175 MeV/m accelerating gradient and a 375 MeV/m peak electric field, with an electric breakdown probability of 1/J/pulse/m being as low as 10^-7. This level of accelerator performance can be sustained at room temperature (300 K), by the way, which makes it even more impressive. It turns out that permanent magnets can be used to substitute the need for electromagnets as well, making this neodymium N52 technology even more promising, because it should be feasible to use it to steer the beam from a linear accelerator at the beam exit. I have a lot of math and physics to learn before I can even begin to construct a 1.5 GeV/10 mA (15 MW) continuous wave proton beam accelerator whose RF cavity is only 10 m in length, 10 metric tons in mass, and requires not more than 30 MW for total power operation. Now, that's where I think those dilithium crystals are sure to come in handy!
I bought some ebay irfp460 mosfets and they had been ground down and reprinted... I tested them with a transistor tester and found that they were different. Half of them were one kind and the other half were another kind... they still worked for the project I had but who knows if they would work as a direct replacement without causing a problem.
When it comes to after market electronic parts stories like yours are common. Sometimes it's best to pay a little extra from companies like Digikey who have a good reputation.
@@GrantsPassTVRepair I've even bought pure nickel battery tabs and when they showed up they were very magnetic, far more than nickel should ever be... trying to save the little money I have usually bites me in the butt eventually.
I recycle my Neodymium magnets from faulthy harddrive's, they have not the circular form like those you order online, but these are the real ones and are usefull for many purposes. One of the major purposes here is too hold screwdrivers, pliers etc....
I also have many of the hard drive magnets, and yes they are amazing, Their north and south poles are both on the face of the magnets which isn't ideal for my experiments, but they are great for hanging tools or picking things up.
I have some solar powered garden lights the string type,if I were to fix small neodymium magnets around my fence would it be ok to stick the lights to them without any problems arising, that way I can take the lights down easier.
they're not fake but it is the process that neodymium magnets are made that makes it impossible to match the pull force exactly when compared to other Neo Magnets with the same N52 rating. All though the magnets are listed as N45 N52 etc but those grades are actually a range that is around N52. So a N52 rated magnet can actually range between N48 all the way to N54 each supplier should be able to tell you the range their N52 actually are. Other factors beyond the range is the actual atomic compounds or ingredients used to create the magnet itself which can be manipulated to add better performance in hot environments. These magnets will have letters after the N rating so N52M will perform up to 200 degrees F.
imho it's worth paying for ebayplus, if you're not happy with an item, ask for a refund, I haven't been refused yet. Stay safe yourself, best wishes from Australia.
Unfortunately I'm not sure because I had bought quite a few before realizing some of them were not as strong as others.. Surprisingly some of the magnets which came directly fron China were fine,
Did you actually check the seller specifications first? Neo magnets are made of a crystalline structure that's impossible to make perfect every time in all of the magnets at an atomic level. So no two magnets are exactly the same. The industry has therefore accepted a range for each grade. The final energy product for an N45 magnet is between 43-45 MGOe. In the high grade N52, where the limit of mass production seems to be at the moment, it's even harder to achieve perfection. Especially in larger magnets.
I understand, but since it was just a small percentage of magnets that had far less strength, I assumed there was a problem as seen by my CRT and the pull test I did.
You should let us know how the vender treated you... include names. For the most part, I do well on ebay but have had a few venders that did me wrong but ebay did help. Carl
Every once in a while I order something from an eBay seller that doesn't work out as well. Just last week I ordered some ferrite rods from a U.S. seller for an antenna project. The seller shipped Qty 5 large rods in a plastic envelope alone, no box at all. Needless to say all that was delivered was residue. Each response from him took between two to four days. First he only offered a small discount, then an offer to reship but I pay shipping FROM CHINA, then another partial refund offer. I politely refused all then escalated to have eBay customer service step in. The key is take photos of packaging and what you received, document - document - document, be polite, don't threaten, have resolve and escalate. I had my full refund from eBay 15 minutes after escalating and that seller is permanently OFF MY LIST.
That's good advice about not threatening people on ebay. I've had similar situations in the past, and Ebay has always been good about making sure the sellers are responsible for their fake or defective products.
Yes it was fine because it was a black and white TV. If you do this with an older style glass tube colorTV you will need to demagnetize the screen if you do this, and you can potentially damage it.
I'm not exactly sure since I ordered them from 4 different companies, and later discovered many of them were not as strong as others, Surprisingly a Chinese company sold me some of the best magnets I have, and they came directly from China. I think the ebay sellers name was besttool2019 The ones I bought were 20mmx40mm.
Come to think of it I do seem to remember warping a shadow mask like this many years ago, but most of the time it was just a matter of having to demagnetize the screen.
It's funny to hear you mention that. Older people my age loose the ability to hear high frequencies, but as a younger person I remember how painful it was to hear the ringing from a cathode ray tube TV. Did my camera actually pick up the ringing noise from the TV?
fckk!! i used to do that just for fun, but never tried a r.e. magnet, didnt spected that result, i had to watch the action four times before notiucing it ws not a papr conic shaped behind the magnet but the catodic deflection caused by the m.f.!!! Cool, suscribed!
Thanks Dave. Doubly enjoy your videos now that I’m “aground”.
Great to see you back! Nearly didn't recognize you with the beard.
I like the easy way how you tested the strength of the magnets 🧲 Good vid! Thx 👍
Good info 👍
Thanks Tampatec.
Thanks much. I was roaming around Amazon trying to find a strong magnet to go meteorite hunting with and did not know that if I ordered an N52 that it might not be what I get.
Guess I have more research to do.
Thanks.
Thank you for your video, I appreciate the information. I was curious to know if these magnets would be useful in accelerating protons in a compact, or even a tabletop, linear or synchrotron accelerator, with an energy gradient of at least 25 MeV/m, in an accelerator cavity not much longer than 10 m, which would be sufficient to produce a beam of 250 MeV protons, which assuming a 1 mA beam current, would result in a 250 kW beam power. I've heard that non-superconducting magnets, the most powerful of which are N52 grade neodymium magnets, are capable of energy gradients of up to 100 MeV/m, and that only superconducting magnets can make that larger; however, I'm not really sure what the true limitations are of non-superconducting magnets, but that's what I've read.
I'd suggest lowering the energy gradient to at least 10 MeV/m to compromise for the reflection factor. This occurs in the cavity due to unstable acceleration characteristics when particle variances occur. 1mA of beem current would be safe enough if you use Dilithium crystals at your input and output ports to avoid any interactions from the cavities self oscillation reactance losses. I will contact the Star Ship Enterprise at 2200 hours and see if we can arrange a pick up date.
@@GrantsPassTVRepair Thanks, I did some research and found that using a special "hard" CuAg alloy for the RF cavity, with 0.08% silver composition, would suffice in achieving a 175 MeV/m accelerating gradient and a 375 MeV/m peak electric field, with an electric breakdown probability of 1/J/pulse/m being as low as 10^-7. This level of accelerator performance can be sustained at room temperature (300 K), by the way, which makes it even more impressive. It turns out that permanent magnets can be used to substitute the need for electromagnets as well, making this neodymium N52 technology even more promising, because it should be feasible to use it to steer the beam from a linear accelerator at the beam exit. I have a lot of math and physics to learn before I can even begin to construct a 1.5 GeV/10 mA (15 MW) continuous wave proton beam accelerator whose RF cavity is only 10 m in length, 10 metric tons in mass, and requires not more than 30 MW for total power operation. Now, that's where I think those dilithium crystals are sure to come in handy!
I bought some ebay irfp460 mosfets and they had been ground down and reprinted... I tested them with a transistor tester and found that they were different. Half of them were one kind and the other half were another kind... they still worked for the project I had but who knows if they would work as a direct replacement without causing a problem.
When it comes to after market electronic parts stories like yours are common. Sometimes it's best to pay a little extra from companies like Digikey who have a good reputation.
@@GrantsPassTVRepair I've even bought pure nickel battery tabs and when they showed up they were very magnetic, far more than nickel should ever be... trying to save the little money I have usually bites me in the butt eventually.
Thanks, Dave. Watch those fingers!
You got that right.
I recycle my Neodymium magnets from faulthy harddrive's, they have not the circular form like those you order online, but these are the real ones
and are usefull for many purposes.
One of the major purposes here is too hold screwdrivers, pliers etc....
I also have many of the hard drive magnets, and yes they are amazing, Their north and south poles are both on the face of the magnets which isn't ideal for my experiments, but they are great for hanging tools or picking things up.
I have some solar powered garden lights the string type,if I were to fix small neodymium magnets around my fence would it be ok to stick the lights to them without any problems arising, that way I can take the lights down easier.
thank you for making this
Was that blood blisters on your finger? Good ol neodymium
Thanks for that information because I felt the same way but I never proved it
Thanks
they're not fake but it is the process that neodymium magnets are made that makes it impossible to match the pull force exactly when compared to other Neo Magnets with the same N52 rating. All though the magnets are listed as N45 N52 etc but those grades are actually a range that is around N52. So a N52 rated magnet can actually range between N48 all the way to N54 each supplier should be able to tell you the range their N52 actually are. Other factors beyond the range is the actual atomic compounds or ingredients used to create the magnet itself which can be manipulated to add better performance in hot environments. These magnets will have letters after the N rating so N52M will perform up to 200 degrees F.
Hello .now I have to go search for a old time black and white TV to test my magnets it's funny how things like that could be useful as a tool.
Cool stuff stay safe 😷 👍
imho it's worth paying for ebayplus, if you're not happy with an item, ask for a refund, I haven't been refused yet.
Stay safe yourself, best wishes from Australia.
I don't have ebay plus, but ebay has still been great about making sure the bad sellers do right by me.
Could you let me know one of the sellers that sold magnet of correct strength?
Unfortunately I'm not sure because I had bought quite a few before realizing some of them were not as strong as others.. Surprisingly some of the magnets which came directly fron China were fine,
Did you actually check the seller specifications first?
Neo magnets are made of a crystalline structure that's impossible to make perfect every time in all of the magnets at an atomic level. So no two magnets are exactly the same. The industry has therefore accepted a range for each grade. The final energy product for an N45 magnet is between 43-45 MGOe. In the high grade N52, where the limit of mass production seems to be at the moment, it's even harder to achieve perfection. Especially in larger magnets.
I understand, but since it was just a small percentage of magnets that had far less strength, I assumed there was a problem as seen by my CRT and the pull test I did.
You should let us know how the vender treated you... include names. For the most part, I do well on ebay but have had a few venders that did me wrong but ebay did help. Carl
Yes ebay is good about taking care of the buyers.
The description on one said 18 lbs of force! That a fridge magnet
So who was the vendor?
The sellers name was USA-Cyberlink.
Is there a way to remagnitize them
None that I'm aware of which can make the strong magnetic field like it is when they are manufactured.
Every once in a while I order something from an eBay seller that doesn't work out as well. Just last week I ordered some ferrite rods from a U.S. seller for an antenna project. The seller shipped Qty 5 large rods in a plastic envelope alone, no box at all. Needless to say all that was delivered was residue. Each response from him took between two to four days. First he only offered a small discount, then an offer to reship but I pay shipping FROM CHINA, then another partial refund offer. I politely refused all then escalated to have eBay customer service step in. The key is take photos of packaging and what you received, document - document - document, be polite, don't threaten, have resolve and escalate. I had my full refund from eBay 15 minutes after escalating and that seller is permanently OFF MY LIST.
That's good advice about not threatening people on ebay. I've had similar situations in the past, and Ebay has always been good about making sure the sellers are responsible for their fake or defective products.
That is good to know that people are trying to rip people off with less quality magnets. Did your television ever come back to normal?
Yes it was fine because it was a black and white TV. If you do this with an older style glass tube colorTV you will need to demagnetize the screen if you do this, and you can potentially damage it.
I guess if they were all fake you wouldnt know unless you had something to compare them to.
Unfortunately your right. I was fortunate to have a stronger magnet to compare them to.
Where can I buy these but like not the fake ones lol
I'm not exactly sure since I ordered them from 4 different companies, and later discovered many of them were not as strong as others, Surprisingly a Chinese company sold me some of the best magnets I have, and they came directly from China. I think the ebay sellers name was besttool2019 The ones I bought were 20mmx40mm.
@@GrantsPassTVRepair thanks Dave! If u ever find out for sure where u got your strongest magnets please let me know for now I'll go look at besttool:)
@@Earlingtons Will do.
Only want to do that on a black and white TV or you'll have a bent shadow mask.
Come to think of it I do seem to remember warping a shadow mask like this many years ago, but most of the time it was just a matter of having to demagnetize the screen.
@@GrantsPassTVRepair I own a degaussing coil for that, too.
Is no one gonna talk about the ringing? Or is that just me?
It's funny to hear you mention that. Older people my age loose the ability to hear high frequencies, but as a younger person I remember how painful it was to hear the ringing from a cathode ray tube TV. Did my camera actually pick up the ringing noise from the TV?
Yep
Also i didnt know that those tvs make those sounds because i have a samsung one and they are not as old.
yeap, its the old tv, i remember as a kid i could "hear" it from outside of a house and i knew when tv was on or off
get what you ordered or get refund,,I never settle for less
Yes absolutely.
fckk!! i used to do that just for fun, but never tried a r.e. magnet, didnt spected that result, i had to watch the action four times before notiucing it ws not a papr conic shaped behind the magnet but the catodic deflection caused by the m.f.!!!
Cool, suscribed!