The story behind
Magnetometer kit
Invented originally in early 90’s by the engineer Dr Noble in Wales UK, the FGM series of flux gate magnetometer sensors was distributed by the partner Bill Speake through his established company Speake & Co Llanfapley based in Abergavenny Monmouthsire, and regularly supplied to our company.
We took it one step further…
Speake sensors business closed…
Electronics boards
Inside the process…
FGM 3 PRO Sensor Cutout
The new FGM 3 PRO type version sensor now has more sensitivity, gained primarily by using in our manufacture higher conductivity materials in the internal sensor structure.
Photos from our ready made magnetometer kits
A walk inside the laboratory…
Inside the process…
Building a gradiometer kit…
Also, as 2 magnetic field sensors are required as a pair to build a gradiometer kit, their electric properties must be equally balanced for both sensors. In the original FGM sensor design and various web site offered FGM imitations the matching procedures for every pair were not implemented. We are dedicated to match every pair of magnetometer sensors produced so that their voltage outputs will be exactly the same.
Therefore the gradiometer kit you receive will only have to be adjusted by aligning the sensors (for canceling the earth magnetic field as you will read in the pdf), and not any interference signal occurs from a pair where one magnetic field sensor has a different signal output compared to the other. The sensor pair matching enables you to align the sensors easier and faster as it has minimized false magnetometer signal effects.
FGM 3 PRO gradiometer sensors are matched in pairs with equal electronic properties?
The signal output on every individual FGM 3 PRO sensor has been tested in our lab and marked by hand on its label. To construct a reliable gradiometer both sensors have to produce exactly the same signal output, otherwise noise and unstable operation occurs. The pair of gradiometer sensors you will receive has been selected so that both sensors are matched to produce exactly the same signal output. In other words, every pair has the same linearity, and the end result is great depth performance. The output of each sensor is marked outside and matches to the sensor that it has been paired with.
Positioning the sensors
The magnetometer kit electronics board is pre-assembled and also tested. The board includes an LCD that monitors each sensor readings with +/- polarity signs and numerical values, has a battery status meter and a timer for the initial startup sensor balancing. The target audio signal is a precise VCO with frequency output range 0-3000 Hz through a speaker.
