TM-9-1290-365-24&P Technical and Parts Manual for Paladin Muzzle Velocity System M93 Upgraded Download
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ARMY TM 9-1290-365-24&P D.9.3.2.2 Insertion Loss Without PIN Switch. The calibration of the microwave measurement equipment setup is performed in the following way: a. The PIN switch and dummy load are disconnected from the test setup. b. A power meter is connected to the coupling output of the directional coupler and to the output of the 20dB fixed attenuator. c. A signal source of 0 to 2OdBm power (Pi) and frequency of 10525±25MHz is inserted through the SMA female/female adapter. d. The variable attenuator is set to 0dB attenuation. e. The phase shifter is adjusted for maximum power on the fixed attenuators output. f. The power on the fixed attenuator output and the coupling output are recorded. Pc(dBm) = Coupling output Pa(dBm) = Fixed attenuator output g. The insertion loss for both outputs is calculated: Kp = Pi - Pc (coupling attenuation factor in dB) Ka = Pi - Pa (insertion loss at fixed attenuator output in dB) Pi = input power from the signal source in dBm D.9.3.2.3 Return Loss of the PIN Switch. The PIN switch is tested for its return loss (RL) when the switch is off. The OFF position is defined while the PIN SW is set to isolate between input and output port, and reflect the power to the input port. The PIN switch is biased in accordance with its manufacturers requirements during tests. NOTE For this test, the PIN SW. output of the test fixture AY6708043-0 can be used to bias the tested PIN switch. Refer to Figure D-41 . D.9.3.2.4 Calculation of Overall Insertion Loss. The overall insertion loss of the microwave test equip- ment setup is calculated as follows: Ks=2xKa+ RL+3dB+9.94dB where: Ks = overall insertion loss factor in dB 2 = multiplier for a signal travelling both ways Ka = insertion loss of the microwave test equipment setup as was previously measured RL = return loss of the PIN switch in dB 3dB = correction for -3dB power reflection as a result of on/off chopping of the signal by the PIN switch. 9.94dB = correction for -9.94dB in reflected power as a result of the first spectral component. D.9.3.2.5 Factor Marking. The coupling attenuation factor (Kp) and the overall insertion loss factor (Ks) are marked using a sticker on the directional coupler as follows: Kp=XX.XdB Ks = XX.X dB XX.X = the result achieved after calculations. END OF CALIBRATION D-118