Grumpy:
I have a helpful suggestion for you. I am not sure if you are familiar with the mathematical concepts of differentiation and integration.
With respect to integration you probably know that it is a form of addition. There are two simple examples that I can think of. When you take a picture with a film or a CCD camera the image sensor adds up all of the light. The light can vary during the exposure and the integrating function of the film or CCD sensor copes with that and still gives you a proper result.
The other is filling up a sink with water. You can vary the water flow and the water level in the sink gives you the integration of the water flow x time.
So imagine you make a loop of solid insulated wire perhaps two inches in diameter and you connect it to a length of coax that terminates in a standard BNC connector. Say you make the loop with three turns of wire.
Now for step one you can run some experiments and position the loop and look at the scope display. You should see "heartbeat" spikes on the scope display that spike up and spike down whenever you have a pulse event that creates a pulsed magnetic field.
Then the next step would be to feed the signal into an operational amplifier setup that you make on a small project board. The operational amplifier is configured to perform integration on the input signal. This means that there is a capacitor in the negative feedback loop of the operational amplifier that performs the actual integration. It would also need to have a reset button to zero out the integration.
http://webpages.ursinus.edu/lriley/ref/circuits/node5.htmlhttp://focus.ti.com/lit/an/sboa092a/sboa092a.pdfhttp://www.national.com/an/AN/AN-31.pdfOperational amplifiers are like gold, they really are. They do similar things to what transistors do but a 1000 times better.
Continuing on, you need to connect the output of the operational amplifier to a peak detector. The reason for this is that the output from your loop for a magnetic field impulse is always going to have a positive and negative spike, and the two spikes will cancel each other out when the integration is done.
So, you probably can also find an operational amplifier circuit that uses a diode as the basis for peak detection, but one more time it will be 1000 times higher in performance than a peak detector based on a diode alone. The peak detector will also have a push button to reset it.
So your test sequence would be as follows: 1) Reset your integrator and your peak detector with your push buttons. 2) Fire your pulse circuit that generates the magnetic field pulse. 3) Read the voltage on the peak detector. 4) Reset your peak detector. 5) Go to step 1.
The key point here is that you could adjust the input gain of your integrator and increase the size of your integrating capacitor if you need to. So it should be possible to make measurements of very high magnetic field pulses by adjusting the integrator settings.
I realize that this might be advanced for you and it would even be a challenge for someone with a lot of analog bench experience. I am just giving you a rough sketch here. However, it certainly is an interesting concept. It sounds like it would be right up Giantkiller's alley also.
This is not an open invitation to give anybody tech support. With a lot of work and experimentation I think it is all doable though.
MileHigh