  We have measured high frequency magnetotransport of a high quality
two-dimensional electron system (2DES) near the reentrant insulating phase
(RIP) at Landau fillings ($\nu$) between 1/5 and 2/9. The
magneto\textit{conductivity} in the RIP has resonant behavior around 150 MHz,
showing a \textit{peak} at $\nu$$\sim$0.21. Our data support the interpretation
of the RIP as due to some pinned electron solid. We have also investigated a
narrowly confined 2DES recently found to have a RIP at 1/3$<$$\nu$$<$1/2 and we
have revealed features, not seen in DC transport, that suggest some intriguing
interplay between the 1/3 FQHE and RIP.
