  We demonstrate time reversal of nuclear spin dynamics in highly magnetized
dilute liquid 3He-4He mixtures through effective inversion of long-range
dipolar interactions. These experiments, which involve using magic sandwich NMR
pulse sequences to generate spin echoes, probe the spatiotemporal development
of turbulent spin dynamics and promise to serve as a versatile tool for the
study and control of dynamic magnetization instabilities. We also show that a
repeated magic sandwich pulse sequence can be used to dynamically stabilize
modes of nuclear precession that are otherwise intrinsically unstable. To date,
we have extended the effective precession lifetimes of our magnetized samples
by more than three orders of magnitude.
