A probe for an NMR device is disclosed in which a saddle coil is disposed on one side of a flexible insulating material, and an additional conductor is disposed on the opposite side. The additional conductor and the conductors of the saddle coil create a capacitance across the insulating material. This capacitance acts with the inductance of the saddle coil such that the probe itself forms a transmission line. The probe is thus inherently broadband and requires no tuning. It also presents a constant impedance, thus facilitating impedance matching to an NMR spectrometer. In a preferred embodiment, a chip resistor is disposed on the flexible insulating material, terminating the transmission line.