FrSky has enhanced the performance and capability of the original sensor line, resulting in the development of the new ADVANCE (ADV) series sensors. All ADV sensors fully support FBUS protocol and they are also S.Port compatible. With the FBUS protocol, the ADV sensors can be seamlessly paired with the FBUS capable receiver which further simplifies model builds.
The VARI ADV variometer sensor calculates the altitude from atmospheric pressure, and atmospheric pressure will get lower as you go up in altitude, with using this the sensor can measure the altitude up to 10000 meters with an accuracy tolerance of 0.1 meters. An exact measurement cannot be performed if atmospheric pressure changes in weather.
● Type: Variometer Sensor
● Dimensions: 40*21*6.5mm (L*W*H)
● Weight: 3.4g
● Measures: -1800 ~ 10000m with 0.1m
● Operational Voltage: DC 4-10V
● Operational Current: 4mA
● Units: Metric or British units
Manual and firmware here