From: Roland, J., G. McKinnon, C. Backhouse & P.D. Taylor. 1996. Even smaller radar tags on insects. Nature 381:120.
The tag is glued to the insect thorax or abdomen with rubber cement, and the near-invisible dipole simply trails behind the insect. This configuration is two orders of magnitude lighter than that used for tracking ground beetles, and an order of magnitude lighter than that used for tracking bees. Our transmitter-receiver (RECCO Rescue Systems, Lindingo, Sweden) is carried in a portable backpack, weighs 8 kg and transmits a 1.7W continuous microwave frequency of 917MHz from a hand-held Yagi antenna. The tag on the target insect reflects this energy at a frequency of 1,834 MHz, whick is detected by the same hand-held antenna. The use of a longer frequency than that used for tracking bees reduces the antenuation of the signal by water in intervening vegetation. The current configuration of transmitter-receiver and dipole permits detection at up to 50m. Tagged insects are relocated at intervals by systematic searching and triangulation on the reflected signal.