FAQs
Q: To what depth can I detect features with the Grad601 magnetic gradiometer?
A: The Grad601 magnetic gradiometer uses sensors with a 1m separation to give a greater response from deeper objects compared to a gradiometer with a sensor separation of only 0.5m. The maximum depth for detection will depend on the size, shape and magnetic properties of the object compared to the background material. However, the instrument is designed specifically for archaeological surveys and typically detects features up to 2m.
Q: Where are the sensors positioned in a Mag-03 and what is the positional tolerance?
A: The position and direction of the three sensing elements is shown by three arrows marked on the enclosure. The sensing elements are positioned beneath these arrows and are on the central axis of the magnetometer. The output is positive when the arrow points to magnetic north. The dimensions and tolerances are shown in the outline drawing for each magnetometer at the back of the Mag-03 Operation Manual. Follow the link to Operation Manuals and select the PDF file for OM1004.
Q: What measurement resolution is possible with the Mag-03?
A: The Mag-03 has an analog output with a very high linearity. The measurement resolution that can be achieved will depend not only on the internal noise of the sensor but also on the resolution and bandwidth of data acquisition system. The output signal will contain components at the power line-frequency and the 15 kHz operating frequency of the sensor. The 15 kHz component is outside the bandwidth of the sensor and can be easily removed with a low-pass filter. For AC measurements using a standard sensor with a measurement range of ±100uT, a resolution of better than 10nT can be expected using a 16-bit A/D converter. Higher resolution can be obtained by backing off the DC component and applying gain to the remaining AC component. This can be achieved by processing the analog signal using the Mag-03SCU signal conditioning unit or digitally using the Spectramag-6 data acquisition and spectrum analyser. For low frequency and DC measurements, a higher resolution can be achieved using signal averaging.
Q: What else do I need to measure magnetic fields with the Mag-03 sensor?
A: A minimum system comprises a Mag-03 magnetometer, a ±12V power supply, a connecting cable for the power supply and output signals and a voltage measurement or data acquisition system for the three output signals.
Q: Does Bartington Instruments design/manufacture resistivity instruments ?
A: No, at the current time, we only design magnetometry instruments.
A: The Grad601 magnetic gradiometer uses sensors with a 1m separation to give a greater response from deeper objects compared to a gradiometer with a sensor separation of only 0.5m. The maximum depth for detection will depend on the size, shape and magnetic properties of the object compared to the background material. However, the instrument is designed specifically for archaeological surveys and typically detects features up to 2m.
Q: Where are the sensors positioned in a Mag-03 and what is the positional tolerance?
A: The position and direction of the three sensing elements is shown by three arrows marked on the enclosure. The sensing elements are positioned beneath these arrows and are on the central axis of the magnetometer. The output is positive when the arrow points to magnetic north. The dimensions and tolerances are shown in the outline drawing for each magnetometer at the back of the Mag-03 Operation Manual. Follow the link to Operation Manuals and select the PDF file for OM1004.
Q: What measurement resolution is possible with the Mag-03?
A: The Mag-03 has an analog output with a very high linearity. The measurement resolution that can be achieved will depend not only on the internal noise of the sensor but also on the resolution and bandwidth of data acquisition system. The output signal will contain components at the power line-frequency and the 15 kHz operating frequency of the sensor. The 15 kHz component is outside the bandwidth of the sensor and can be easily removed with a low-pass filter. For AC measurements using a standard sensor with a measurement range of ±100uT, a resolution of better than 10nT can be expected using a 16-bit A/D converter. Higher resolution can be obtained by backing off the DC component and applying gain to the remaining AC component. This can be achieved by processing the analog signal using the Mag-03SCU signal conditioning unit or digitally using the Spectramag-6 data acquisition and spectrum analyser. For low frequency and DC measurements, a higher resolution can be achieved using signal averaging.
Q: What else do I need to measure magnetic fields with the Mag-03 sensor?
A: A minimum system comprises a Mag-03 magnetometer, a ±12V power supply, a connecting cable for the power supply and output signals and a voltage measurement or data acquisition system for the three output signals.
Q: Does Bartington Instruments design/manufacture resistivity instruments ?
A: No, at the current time, we only design magnetometry instruments.
