# Measuring magnetic waveforms from coil

Thread Starter

#### josh_TMS

Joined Feb 20, 2023
1
Hi all,

Looking to measure some magnetic waves being generated at an electric coil. Freq is between 0-20kHz and magnitude is pretty small <1T. Any have suggestions for the best tool to measure and log data of this magnetic waveform?

Googling around, I found meters like this: https://www.alphalabinc.com/product/mr3/
I thought maybe even a simple hall sensor but not sure.

What do you suggest?

Thanks!

#### Curt Carpenter

Joined Jun 25, 2018
31
How can you couple to the coil to take your measurements?

#### Papabravo

Joined Feb 24, 2006
20,122
Hi all,

Looking to measure some magnetic waves being generated at an electric coil. Freq is between 0-20kHz and magnitude is pretty small <1T. Any have suggestions for the best tool to measure and log data of this magnetic waveform?

Googling around, I found meters like this: https://www.alphalabinc.com/product/mr3/
I thought maybe even a simple hall sensor but not sure.

What do you suggest?

Thanks!
What measurement range will a simple sensor get you? Since magnetic induction is a vector, you will need three sensors, one for each component. Then you will need to compute the magnitude by knowing the magnitudes of the three components. Lastly you will need to compute the direction of the magnetic induction vector by using the magnitude and direction of the three components. This should be a piece of cake for a suitably robust DSP, once you identify an appropriate sensor.

#### Papabravo

Joined Feb 24, 2006
20,122
Here is a typical transfer characteristic:

Using the conversion factor of 1 Gauss = 1e-04 Tesla, a range of ±400 Gauss is equivalent to ±40 mT. This range may or may not be suitable for your purposes, but it seems rather limited to me.

#### grdunc

Joined Mar 27, 2023
1
Hi all,

Looking to measure some magnetic waves being generated at an electric coil. Freq is between 0-20kHz and magnitude is pretty small <1T. Any have suggestions for the best tool to measure and log data of this magnetic waveform?

Googling around, I found meters like this: https://www.alphalabinc.com/product/mr3/
I thought maybe even a simple hall sensor but not sure.

What do you suggest?

Thanks!
A Hall effect sensor will work if the field strength and frequency is within the operation range. There are, or al least used to be, some giant mangetorestrictive devices. As I remember these will work from DC to the range you want but be sure to check the range and noise specifications.
Good Luck