The STP components are cast in an epoxy tube which measures 63mm in length and 21.5mm in diameter. The thermistors are attached to a titanium ring to minimize the temperature response time. The STP is turned on (deployed) and off (in stand-by) with a magnet. An LED flashes in response to confirm whether the STP is “on” or “off.”
The STP3 is the third generation Wildlife Computers stomach temperature pill transmitter, and is used in conjunction with a Mk10-L or Mk10-AL receiver. Four thermistors monitor temperature, and the coldest measured temperature is relayed to the recorder using a coded message. Users can choose a transmission interval of 10, 20, or 30 seconds. The STP3 is calibrated to measure 0 to 50°C, with a resolution of 0.1°C, and accuracy of approximately ± 0.3°C.
Any STP3 manufactured in October 2007 or later may be within as little as 1.5 to 2cm from the receiver, which is helpful for studies of pups or smaller animals.
The STP2 is our second generation “Stomach Temperature Pill.” It is used in conjunction with an HTR (which is no longer manufactured). Four thermistors monitor temperature, and the coldest measured temperature is relayed to the HTR. The STP2 must be within approximately 1.5m of the HTR. The STP2 “pings” a radio-pulse of 5kHz. The ping-rate is temperature-dependent; the warmer the temperature, the faster the ping-rate. The STP2 is calibrated to measure 0 to 50°C, with a resolution of 0.1°C, and accuracy of approximately ± 1°C. Battery life is expected to be approximately 20 days.