Procedure in radio sonde - used when transferring signals measured with capacitive sensors, to surface station by radio transmitter (sf 28.2.79)

摘要

Signals measured with capacitive sensors (A) are transferred to a surface station by a radio transmitter (D, E). The procedure comprises the following phases: (a) to create a capacitive signal (CM) that depends on the quantity being measured; (b) to control an oscillator that has an output frequency of the order of 1 to 10 MHz with a capacitive signal so to make the output frequency dependent on the capacitive signal; (c) to divide the output frequency of the oscillator with factor D, which is of the order of 26 to 28, preferably 27 (D=27); (d) to frequency modulate the high frequency transmitter (D).