Gaussmeter Recommendation

[Daver]

Looking for input on a good gaussmeter that won't break the bank for checking magnets. What do you guys use/recommend? Thanks!

Daver

[nosaj]

Looking for input on a good gaussmeter that won't break the bank for checking magnets. What do you guys use/recommend? Thanks!

Daver

Will this work?
Build your own Gaussmeter

nosaj

[Daver]

I don't know. I guess I'm not 100% sure what I need as far as specs go to do the measurements. Thanks!

[big_teee]

The two meters that come to mind that a lot of the group have used, are no longer being made and sold.
I did a search on Amazon, and a bunch of items came up, don't know anything about any of them.
But, it may help you in your research.
https://www.amazon.com/s/ref=sr_st_p...price-asc-rank
GL,
T

[Daver]

Thanks, big teee. I've done searches too on Amazon, eBay, Google, etc.. I get a lot of meters for ghost hunting and things like that. What are you guys using that's not available anymore? Maybe I can find one used. What specs should I be looking for in a new meter? Thanks.

[big_teee]

The Elepro gauss meter is one used a lot.
http://music-electronics-forum.com/t20033/
The Spin Doctor is the other one.
Spin Doctor E.R.
Neither are being built at present.
T

[Daver]

Thanks very much!

[MarkusBass]

I also need a Gaussmeter. So much that I decided to design and build it on my own. But at the moment I'm at the stage of designing the schematic. So it will take at least 2 month more.
The meters listed from Amazon are not good for pickups measurements (and they are to expensive). The meter by Spin Doctor I think is to fragile (prone to failure) and the other one is just to big (and has no enclosure). Maybe these were the reasons why they are not manufactured any more .

Mark

[the great waldo]

I also need a Gaussmeter. So much that I decided to design and build it on my own. But at the moment I'm at the stage of designing the schematic. So it will take at least 2 month more.
The meters listed from Amazon are not good for pickups measurements (and they are to expensive). The meter by Spin Doctor I think is to fragile (prone to failure) and the other one is just to big (and has no enclosure). Maybe these were the reasons why they are not manufactured any more .

Mark

Hi Mark

Elepro's meter works great, maybe you can make something along those lines. Elepro has been offline for quite a while, maybe he's still busy with the house renovations. It would be nice to hear from him as his projects were always interesting.
Cheers
Andrew

[MarkusBass]

Thanks but, as you say, he is offline for a long time. I want to build my own. It should be slightly better than what I've seen. It will use rechargeable battery, OLED display, nice enclosure any it will be small. I'm collecting requirements at the moment.

Mark

[rjb]

Some info from K&J Magnetics:

https://www.kjmagnetics.com/blog.asp?p=measuring-magnets
We’re using an old model from Trifled/Alphalab in the photos in this article, but there are similar instruments from other companies as well. We don’t sell these instruments here at K&J Magnetics, but you can find them online. Here are a few reputable products:

• http://www.trifield.com/content/dc-g...-model-gm1-st/: An updated version of the one shown here.
• http://www.lakeshore.com/products/Ga...er-Models.aspx: Their model 410 is a simple, single-axis product similar in function to the one we’re using.
• MAGNET-PHYSIK Dr. Steingroever GmbH: Field Strength Meter and Sensors: Offerings from Magnet-Physik.

"Make a magnetometer for under $10!" https://www.kjmagnetics.com/blog.asp?p=gaussmeter

-rb

[MarkusBass]

Thanks but these are a little bit to expensive for me ($500 to $4000). Also I don't want to measure rare earth magnets but just pickups.
The last one is good for experiments but not as a tool for a luthier's workshop.

[Daver]

Thanks for the links, rjb. Those are a bit expensive for me, too and the home built version seems a bit fiddly and not too accurate. I'm very surprised there isn't anything out there for a reasonable price that measures gauss in the range guitar pickup operate and has a display.

Daver

[rjb]

Sure, the K&J DIY setup wouldn't be as compact and slick as the Elepro or Spin Doctor. But they're not made anymore!

Since all these units probably use the same Allegro A1302 Ratiometric Hall Effect Sensor, I don't think a home-made gaussmeter would be any less accurate- once you get it calibrated. So use trim pots. In the U.S., you often can get a 3-1/2 digit DMM "FREE with any purchase" with a coupon at Harbor Freight. You could dedicate a free DMM to the gaussmeter, and house the whole shebang in an enclosure. It wouldn't be pretty, but it would work.

If you really need greater accuracy, Allegro makes A132X family sensors with greater sensitivity (and the disadvantage of smaller overall range) than the A1302. All are powered at Vcc=5VDC and output 1/2 Vcc at 0 Gauss. I think production of the A1302 is discontinued, but stock is still available. The A132X family sensors are the "new and improved" product. According to K&J, the A1302 has sensitivity 1.3mV/G and output range of +/- 1690 G. Assuming rail-to-rail output for the A132X family, relevent specs are:
A1302 Sensitivity: 1.3 mV/G Output Range: +/-1690 G
A1324LUA-T Sensitivity: 5.000 mV/G Output Range: +/-500 G
A1325LUA-T Sensitivity: 3.125 mV/G Output Range: +/-800 G
A1326LUA-T Sensitivity: 2.500 mV/G Output Range: +/-1000 G

For reference, this chart shows 660 G for fully charged PAF to 1620 G for A8.
http://music-electronics-forum.com/t20638-2/#post170753

But readings "string distance" away from the magnet are more on the order 100-150 G. Or so thay say.

-rb

[Daver]

How about this? https://www.ebay.com/itm/WT10A-LCD-T...0AAOSw44BYJEAu It seems to have enough range.