  Echo atom interferometers have emerged as interesting alternatives to Raman
interferometers for the realization of precise measurements of the
gravitational acceleration $g$ and the determination of the atomic fine
structure through measurements of the atomic recoil frequency $\omega_q$. Here
we review the development of different configurations of echo interferometers
that are best suited to achieve these goals. We describe experiments that
utilize near-resonant excitation of laser-cooled rubidium atoms by a sequence
of standing wave pulses to measure $\omega_q$ with a statistical uncertainty of
37 parts per billion (ppb) on a time scale of $\sim 50$ ms and $g$ with a
statistical precision of 75 ppb. Related coherent transient techniques that
have achieved the most statistically precise measurements of atomic g-factor
ratios are also outlined. We discuss the reduction of prominent systematic
effects in these experiments using off-resonant excitation by low-cost,
high-power lasers.
