  We report experimental control of chaos in an electronic circuit at 43.9 MHz,
which is the fastest chaos control reported in the literature to date. Limiter
control is used to stabilize a periodic orbit in a tuned collector transistor
oscillator modified to exhibit simply folded band chaos. The limiter is
implemented using a transistor to enable monitoring the relative magnitude of
the control perturbation. A plot of the relative control magnitude vs. limiter
level shows a local minimum at period-1 control, thereby providing strong
evidence that the controlled state is an unstable periodic orbit (UPO) of the
uncontrolled system.
