Telemetry Transmitter with Continual Calibration for Precise Measurement of Body Temperatures of Large Animals
ABSTRACT A telemetry transmitter for precise measurement and transmission of two body temperatures from large animals was developed and tested. An updating calibration procedure allows body temperatures to be measured remotely for over 2 wk with an accuracy greater than ±0.10 °C without battery replacement. The unit was designed for external attachment to the animal (back-pack) and has two thermistor probes for temperature sensing. The measured temperatures and calibration signals are transmitted by multiplexed subcarrier modulation of a single carrier frequency in the 88-108 MHz FM band.