We demonstrate how the communication reliability in a sensor network (end-to-end delivery ratio and network stability) can be improved by exploiting transceiver diversity. A new sensor platform, Opal, which features a dual radio configuration working in the 900 MHz and 2.4 GHz band, but driven by a single micro-controller is the basis of the demonstration. A new dual radio collection tree protocol network architecture is designed to provide a transparent communication stack to the upper layer users in TinyOS.