R 1EFF : 001-049, 101-105, 151-199, 1 34-41-00Page 33 1 1 Config-3 May 01/05 1 1 1CES 1

 (1)
 Not Applicable

 (2)
 Not Applicable

 (3)
 Not Applicable

 (4)
 Not Applicable

 (5)
 Not Applicable

 (6)
 Not Applicable

 (7)
 Not Applicable

 (8)
 Not Applicable

 (9)
 Not Applicable

 (10) Not Applicable
 (11) Not Applicable R **ON A/C 051-099, 106-149, 201-299, 301-399, 401-499,
 A. Transceiver
 **ON A/C 051-099,

 (Ref. Fig. 006A) R **ON A/C 106-149, 201-299, 301-399, 401-499,
 (Ref. Fig. 006B) R **ON A/C 051-099, 106-149, 201-299, 301-399, 401-499,
 (Ref. Fig. 007A)
 The weather radar transceiver with PWS is a completely solid-state
 airborne unit.
 It contains:

 1EFF : ALL 1 34-41-00Page 34 1 1 Config-3 Aug 01/05 1 1 1CES 1

 Weather Radar Transceiver - Component Description
 Figure 007A

R 1EFF : 051-099, 106-149, 201-299, 301-399, 1 34-41-00Page 35 1401-499, 1Config-3 Aug 01/05 1 1 1CES 1

 (1)
 A power amplifier A single 777.77 MHz multiplier drive signal is developed by the power amplifier. The power amplification of the transmit section is accomplished by splitting the power amplifier drive before recombining the signals into a single multiplier drive signal.

 (2)
 A power multiplier The power multiplier produces the 9333.24 MHz transmitter output signal from the single multiplier drive signal (from the power amplifier). The multiplier drive signal is multiplied by 3 to produce a 2333.31 MHz signal. The 2333.31 MHz signal is their quadrupled to produce the 9333.24 MHz transmitter output signal.

 (3)
 A duplexer/monitor The transmitter output is coupled through a duplexer/monitor to the waveguide antenna feed through a 4-port circulator. Incorporated in the duplexer operation are monitor circuits to monitor the output power level and develop a frequency loop error signal for the correction of frequency chirp. The monitor circuit also accepts a test signal which causes a portion of the reference signal to be injected into the receiver for test calibration. The 4-port circulator also couples the RF return from the waveguide antenna feed through the preamplifier to the receiver portion of the transceiver.

 (4)
 A preamplifier The preamplifier assembly perform the waveguide limiter functions (protects the mixer diodes from all high power pulses), contains a noise diode circuit and contains a 2-stage RF amplifier which provides +18dB of RF gain.

 (5)
 A mixer The mixer circuit processes the detected RF return signal by mixing it with the First local oscillator signal and amplifying the resultant Intermediate Frequency (IF) signal in the First IF amplifier. The first IF amplifier provides 25dB amplification before the First IF signal is applied to the second IF amplifier.

 (6)
 A second IF amplifier The second IF amplifier completes the receiver amplification of the RF return signal. The output from the first IF is converted to the 13.8888 MHz second IF signal by mixing it with the 152.77 MHz second local oscillator signal. The second IF signal is double-buffered and applied to a synchronous detector. The third local oscillator signal

R 1EFF : 051-099, 106-149, 201-299, 301-399, 1 34-41-00Page 36 1401-499, 1Config-3 Aug 01/05 1 1 1CES 1 is phase-split to obtain one signal in phase with the transmitter frequency and one signal phase shifted by 90 deg.

 (7)
 A sampler The sampler commands and controls the receive and transmit functions within the receiver-transmitter. A digital signal processor is used to control transmitter timing and receiver normalizer.

 (8)
 A digital signal processsor
 The digital signal processor circuit card performs the weather
 processing, clutter identification, clutter filtering, velocity
 extraction and editing, hazard computation and hazard recognition
 algorithms. Command and control information is passed from the
 digital signal processor to the sampler through a dual port RAM.

 (9)
 A central processing unit Control of internal functions, antenna servo controls, monitoring of system operation and formatting the processed data is accomplished by the central processing unit. It uses a microprocessor and a stored program to execute the following major routines that control the transceiver and system operations:

 -attitude routine, providing pitch and roll parameters for the stabilization routine
 -stabilization routine, providing elevation position to the elevation maintenance routine
　
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