  A microshot from FRB 20220912A \citep{H23} satisfies the uncertainty relation
$\Delta \omega \Delta t \ge 1$ by a factor of only $\lessapprox 3$. A Crab
pulsar nanoshot \citep{HE07} exceeds this bound by a similar factor. The number
of orthogonal plasma modes contributing to the coherent radiation is also
$\approx \Delta \omega \Delta t$, placing constraints on their excitation and
growth.
