To date most pulsed DNP experiments have been performed at X-band and Q-band because of the availability of pulsed microwave amplifiers at these frequencies. The single time domain DNP experiment performed at W-band (3.4 T) is the SSE/ISE experiment mentioned previously using the HiPER (High Power quasioptical EPR) spectrometer, a design first developed by Smith et al. . The spectrometer used then was equipped with a 94 GHz 1 kW Extended Interaction Klystron (EIK) and NMR console and achieved an enhancement ℇ ~ 70.