The existence of neutrino oscillations demands that neutrinos have non-zero rest mass, the evidence for and implications of which are discussed. Nuclear B-decay is offered as a model-independent tool for direct neutrino mass measurement and contemporary experimental measurements are reviewed. The AMBER experiment is introduced as a novel charge spectrometer, aimed at precision electron energy measurements to probe the structure of the B-spectrum close to its endpoint. AMBER employs a vacuum insulated inverse Kelvin probe to continuously monitor a single rate-of-change observable. A detailed technical description of the technique is provided, followed by proof of principle demonstrations and an examination of hardware performance and its capability to provide sub-eV electron energy resolution. a first order B-spectrum reconstruction algorithm is described and applied to data from a Monte Carlo simulation of a highly idealised AMBER-like model experiment, in which important source scattering effects are neglected, and a calculation of the sensitivity to the neutrino mass is made. Finally the successes and shortcomings of the AMBER technique are discussed.