An ultralight biotelemetry backpack for recording EMG signals in moths

A two-channel FM biopotential recording system fabricated on a foldable, li ghtweight, polyimide substrate is presented. Each channel consists of a bio potential amplifier followed by a Colpitts oscillator with operating freque ncy tunable in the 88-108 MHz commercial PM band. The overall system measur es 10 mm x 10 mm x 3 mm, weighs 0.74 g, uses two 1.5-V batteries, dissipate s about 2 mW, and has a transmission range of 2 m. Using this system, elect romyogram signals have been recorded from the dorsal ventral muscle and the dorsal longitudinal muscle of a giant sphinx moth (manduca sexta).