GELLER Labs "Backyard Science"
Thoughts on a proton precession magnetometer design - a Proton Magnetometer Project. Build an Earth's field magnetometer.
The FDM MAGNETOMETER project is a low cost high performance proton magnetometer (a digital magnetometer) kit under development for amateur scientists to be able to accurately measure and monitor changes in the Earth's total magnetic F field and to observe geomagnetic storms. Magnetic storms can cause large excursions in the field and are of concern to interests ranging from electrical power grids, radio communications, and satellite operations, to aurora watchers and amateur radio operators.
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I created a new Proton Magnetometer Group at Yahoo groups for those interested in discussing proton magnetometers with an emphasis on Earth's field measurements. I will try to keep it as open as possible without getting attacked by spam. I will also try first with no review of posts, let's see what happens. Please keep it friendly and professional. Use of real names is preferred, possibly required in the future.
EDN Magazine, Geomagnetic observatory, Joe Geller, Published EDN online August 12, 2012.
EDN Magazine, Use resistor noise to characterize a low-noise amplifier, Measure gain or noise bandwidth with an AC voltmeter, Joe Geller, edited by Martin Rowe and Fran Granville, EDN, June 23, 2011
PART I: Introduction, Build a Backyard Geomagnetic Observatory! (Ver. 0.8 10/2011) PDF link update - Estimate your local Magnetic Field: NOAA's National Geophysical Data Center (NGDC) Estimated Values of Magnetic Field
PART II: A Brief Survey of Amateur Proton Magnetometers PDF (Ver. 0.6 7/2012)
PART III: A block diagram discussion of the project FDM Proton Magnetometer PDF
PART IV, Building a Sensor Stand and Winding the Sensor Coils (Ver. 0.6 10/2011, does not yet reflect the latest coil and coil form designs, see our journal notes from Jan. 25 to Jan. 27, 2011) PDF
PART V, Building and Testing the Analog Board - Partial Draft on NBLNA testing PDF Here is a sample Excel spread sheet for noise testing of the narrow band low noise amplifier (NBLNA) using resistors and excess Johnson noise XLS, PDF (improved 2/13/11)
PART VI, Operation, Building and Testing the FET-Relay Control Board PDF (Very Rough draft, check back often)
PART VII, FDM Magnetometer Software PDF (Rough draft, check back often) (~4 MB) (July, 2011 needs updating)
PART VIII, System Testing
PART IX, The Gyromagnetic Constant and the Larmor Equation PDF
Safety notice: Generally, no earth grounding is needed at a wood sensor stand. However, if there is any possibility for life threatening electrical potentials and/or currents at your individual sensor stand, than a local earth ground is required for safety reasons, at least when working at the stand. Never disconnect a powered coil when the polarization current is on (there will be a high voltage spike). Also, wear safety glasses and observe good electrical grounding practice for any mains operated power tools while assembling the stand and coil pair. In other words, individual experimenters are solely responsible for their own safety and we (GELLER (Geller Labs) are not in any way responsible for or liable for any injuries incurred while performing this FDM magnetometer experiment. Please do not use our plans or kits if you do not agree to accept full responsibility for your own personal safety.
QUESTIONS/COMMENTS/notice of typos, etc. send email to joegeller @ gellerlabs dot com
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