Field sweep monitoring

At very low frequencies, lookfor externally introduced distortions, such as power-line hum or power supply ripple, and distortions resulting from inadequacies in the video processing equipment. Low-frequency distortions usually appear on the video image as flickering or slowly varying brightness. Low-frequency interference can be seen on a waveform monitor when the DC restorer is set to the slow mode and a 2-field sweep is selected. Sine wave distortion from AC power-hne hum maybe observed in Fig. 20.26. A bouncing... 

Although the entire ESR spectrum of radical species in solids cannot be obtained by the Fourier transform of the ESE signal because of a large spectral width, it can be obtained by monitoring the ESE intensity while sweeping the external magnetic field very slowly. The shape of the ESR spectrum thus obtained is not necessarily the same as that of the cw ESR spectrum. The ESE method detects only the radical species which is not phase-relaxed at the time of detection, so that the radical species with very fast phase relaxation rate cannot be observed by the ESE-detected ESR. 

Fig. 5.—Diagrammatic Representation of the Relationship of the Observe and Irradiate" Fields Used for Performing Various Double-resonance Experiments in the Frequency-sweep Mode. [A, For spin-decoupling, the irradiation field is positioned at the mid-point of the X-resonance B, for spin-tickling, the irradiation field is set on transition X-2 (for both of these experiments, the effect of the perturbation is monitored by scanning the observing field) and C, for an INDOR experiment, the observing field is held positioned on the transition X-2, and now it is the irradiating field that is scanned.]...

Fig. 8. Adiabatic rapid passage signal observed by monitoring the phosphorescence intensity at 456 nm of [Rh (bpy)3] (0104)3 after a rapid microwave sweep through the zero-field I> -1 resonance, at 1.4 K...

Sect. 16.2) An NMR spectrometer that holds the magnetic field constant and slowly sweeps through a range of rf frequencies, monitoring which frequencies are absorbed. 

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