I've seen the simple circuits for Hall effect gaussmeters that can measure refrigerator magnets.(such as http://www.coolmagnetman.com/magmeter.htm) but I'm starting at about 3000 Gauss and going up possibly over 10,000 Gauss (maybe near 20K) using industrial permanent ceramic and metal magnets and condensing the field. If it was calibrated that would be nice, but I would settle for something that can give relative measurements, The metal magnet I started with I measured at 6,500 Gauss 40 years ago. I have no idea how much it has decreased over the years. I have some very large ceramic magnets in the 28 to 80 pound range. Their field strength is unknown. Their weight and the large field area makes working with them dangerous. Sometimes it takes all my strength to just slide one magnet across another. I have been able to add and condense the fields of the ceramics and use them to increase the strength of the metal magnet a small amount. I can already do multiple demonstrations seen on YouTube in which people use Neodymium magnets. Mine have a weak surface field, but it's compensated for by the large area, up to 70 sq. in. It is slow going and involves a lot of guesswork and trial and error to find the best arrangement that will produce the strongest additive field. With a real time measuring device I could condense months of work into a few days. I guess I can assume that if it was possible to fiddle with the simple, weak field circuit to allow measurement of strong fields, someone would have done it by now. This project is not worth spending hundreds of dollars for a meter I may use for only a few days. Even the metal available is too expensive. I found a company that sells pure iron (about the least fancy material) and their smallest piece of rod available was 3-4 feet x 1.25'' diam and cost $4072.00. So I can't even use anything better than steel found in hardware stores
Nevertheless, I've done quite well in general. I've slowed a stack of thin aluminum sheets taped into a stack 3/4'' thick in a gap about 1.25'' wide. Narrowing the gap to about 0.03'' increases the field density greatly. With the narrow gap, my aluminum sheets (1'' wide x 0.025'' thick x 8'' long) will free-fall at less than 1''/second. I'm trying to get all I can out of the materials I have without resorting to using Neodymium (which I've shown I don't need anyway.) The best method I've found of measuring relative increase or decrease in lifting capacity of my metal magnets has been to put playing cards between the magnet and a metal weight. If the magnets got stronger they will lift the weight with more cards between the magnet and weight, and vice versa. The magnet poles are separated enough to measure them individually. My best measurement is usually about 77 cards between one magnet pole and a metal weight of 402 grams (just a convenient weight.) I keep trying to improve on these figures.
I saw in an email an article about a sensor called "Magnetoresistance in Magnetic Field Sensors: Applications for TMR Sensors" so I wondered if this was something I could use? Another idea I had, which would be crude, would be to measure voltage drop, or something, of a low voltage AC current in a small coil which I could place where I wanted to make a measurement. It might be able to give relative differences in field strength I think and let me know if I'm setting things up better or worse than other times.
Thanks.
Nevertheless, I've done quite well in general. I've slowed a stack of thin aluminum sheets taped into a stack 3/4'' thick in a gap about 1.25'' wide. Narrowing the gap to about 0.03'' increases the field density greatly. With the narrow gap, my aluminum sheets (1'' wide x 0.025'' thick x 8'' long) will free-fall at less than 1''/second. I'm trying to get all I can out of the materials I have without resorting to using Neodymium (which I've shown I don't need anyway.) The best method I've found of measuring relative increase or decrease in lifting capacity of my metal magnets has been to put playing cards between the magnet and a metal weight. If the magnets got stronger they will lift the weight with more cards between the magnet and weight, and vice versa. The magnet poles are separated enough to measure them individually. My best measurement is usually about 77 cards between one magnet pole and a metal weight of 402 grams (just a convenient weight.) I keep trying to improve on these figures.
I saw in an email an article about a sensor called "Magnetoresistance in Magnetic Field Sensors: Applications for TMR Sensors" so I wondered if this was something I could use? Another idea I had, which would be crude, would be to measure voltage drop, or something, of a low voltage AC current in a small coil which I could place where I wanted to make a measurement. It might be able to give relative differences in field strength I think and let me know if I'm setting things up better or worse than other times.
Thanks.