Altitude encoder/decoder system consists of two main parts, Altitude encoder and 7 segment decoder. The input and output structure of this unit is consistent with the Altitude encoder system made by Shadin company. The input power of the system is 18 to 36 volts and at 28 volts it consumes a maximum current of 150 mA. In general, this system is used to show the height with a resolution of 100 feet and on 7 segments. Altitude encoder outputs of this collector set are open and as standard, can be connected to other devices that use altitude encoder with coding output. The Altitude encoder block of this unit has an RS232 output that has the height channel data with a resolution of one foot and an output rate of 2 Hz. The system has a potentiometer to adjust the height bias. In general, J1 connectors from Altitude encoder and 7 segment decoder board, Bias potentiometer and static pressure pitot are used by the operator and other connectors are related to the internal communication of the unit.