He figured the oscilloscope was the tool best suited for the task, but he needed a way to pick up the fields and feed them into one of the scope’s probes ... use of a BNC connector for easy ...

So having unboxed it and examined it, we set about hooking it up to the trusty Rigol 1054z ‘scope. The BNC cable is bi-directional, ingeniously if you wire it one way the probe reads voltage ...