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Show APPENDIX B RADAR CALIBRATION The equation for radar reflectivity (Section 2. 0) involves the "radar constants" A2 , c 2 , P , 0, r/J, and h (see Table Bl). These constants must all be known t 2 to determine precipitation rate. (The value for K is dependent upon the state of the -scatterers and for ice is . 19 7. Rt is observed from the recording. P is related to the AGC voltage observed on the recorder, and will be disr cussed in detail on the following page. ) TABLE Bl Radar Constants GPG-1 NIKE G2 = = G2 80. 11 db. = = 3 cm. A e = . 0263 radians e = q) = . 0263 radians q) h = 5400 cm. h A = = 74 db. 3 cm. • 0524 radians . 0525 radians 7500 cm. The value for h can be determined by simply measuring the transmitted pulse length on an oscilloscope. Multiplying the duration of the transmitted pulse, in terms of time, times the velocity of light in free space, c, gives the pulse length of the transmitted pulse in free space, i. e. , h = et (1) The wave length A is given simply by the velocity of light in free space, c, divided by the transmitted frequency f A = c/f 350 (2) |