Gauss meter for strong magnetic fields

[Peregrine]

Hi, how could I measure strong magnetic fields? i made a circuit for PEMF never hall sensors that i have fail to measure it ... in practice it is an LC circuit with C = 60nF and L = 3uH
thanks
Angel

[AstRii]

Measuring strong magnetic fields is really calling out for a hall sensor though. Hall sensors are precise, linear, low hysteresis sensors. The only downside for hall effect sensors is that they do very bad job at measuring weak fields because of Earth's magnetic field, but as you only need to measure strong fields, there is no downside for you.

[davekni]

Agree, at least in theory, that Hall effect sensors would be ideal.  However, most commercial sensor families I've found top out below 0.5T.  I suspect there is insufficient demand for higher field sensing to support volume production of sensors.

For high fields, I find a small coil of wire works quite well.  Easiest if you have a scope with measurement functions for area or average voltage that can be gated with vertical cursors to measure a single half-cycle.  For AC fields (sounds like your case), just insert the coil and measure half-cycle area.  Best to measure both a negative and positive half-cycle and average absolute-value of results in order to cancel out any scope DC offset.  For DC fields, place coil in field, then quickly remove.  Measure area under resulting odd-shaped pulse generated by removing coil.  To cancel scope offset in this DC case, just trigger scope again after coil is out of field, with scope cursors left as they were for measuring odd-shaped pulse.  Resulting area is DC offset to subtract from reading.

[klugesmith]

Yes, what Dave said, if by "strong" you mean 1 tesla (10^4 gauss) or more.
Inexpensive IC's with a Hall plate sensor will, as a rule, have the amplifier saturated at much weaker fields.
For a _lot_ more money, you can get Hall probes with appropriate range and accuracy to go with reputable-brand magnetometers.   
I have never seen a bare Hall-plate sensor device, and if you had one you'd need to deal with calibration and temperature compensation.

So to repeat Dave's suggestion: use the fluxmeter approach.   
Make a sense coil with known area and turns count.   
Measure the area under curve of voltage-time pulse when you rapidly move the coil from "B field under test" to far away.  (this is usually easier than moving it the other way, to end at a precise location).   
It's vastly easier if you are measuring an AC magnetic field at any frequency. 

[edit] OP gives parameters of an LC circuit which, in my unreviewed calculation, rings at 375 kHz.   So frequency response of any sensor, amplifier or integrator circuit, etc is critical.  I'm not familiar with frequency response of amplified Hall sensors, or (e.g.) the sensor in Weston's Little Bee probe.   
375 kHz should be no big issue for metering with a sense coil, if you pay attention to details like the interconnect wires.  What field strength is typical in PEMF apparatus?