AEROGRAPHER'S MATE 3 & 2 



T- 



209.397 

 Figure 4-14. — Data receiver and control as- 

 sembly. 



ANALOG RECORDER (RO-447/GMQ-29( )).— 

 Mounted directly below the Data Receiver and 

 Control Assembly, it is used to record wind 

 direction and spsed (discussed in chapter 3 

 of this manual; see figure 3-4) and precipi- 

 tation to be discussed later in this chapter 

 under rain gages. 



INTERCOMMUNICATIONS GROUP (OA-8785/ 

 GMQ-29( )). — At selected installations the AN/ 

 GMQ-29( ) is equipped with a voice channel, 

 which provides for use of the existing trans- 

 mission lines for the additional purpose of 

 full duplex voice communications between re- 

 mote and local stations. 



Theory of Operation 



Functional operation of the Automatic Weather 

 Station AN/GMQ-29( ) is dependent upon the fol- 

 lowing principles. Individual sensor outputs are 

 converted by their associated signal condition- 

 ers to voltage levels. Timing and control cir- 

 cuits then control data transmission over a 

 single telephone line to the data receiver. Rain- 

 fall information, is accepted by the formatting 

 circuitry directly from its signal conditioner. 

 At the display unit, the data is received, its 

 validity verified and then routed to appropriate 

 internal destinations for computations, record- 

 ing, and display. 



For a more detailed description of the AN/ 

 GMQ-29( ) Automatic Weather Station, refer 

 to NAVAIR 50-30GMQ-29-1, Handbook, Opera- 

 tion, Service and Overhaul Instruction. 



DIGITAL VOITMSUR 



WIND DIRECIION 



• 



a<IMUU T(MP(BAIU»f 



MIN,«UM HMPfBAtUM 





209.398 

 Figure 4-15. — AN/GMQ-29( ) Readout panel. 



Maintenance 



Although most maintenance is performed by 

 the electronic technicians, some maintenance 

 can be performed by the Aerographsr's Mate, 

 This includes the visual inspection of the equip- 

 ment. Refer to Table 14-1 for a complete in- 

 spection list. If no electronic technicians are 

 attached to the unit, refer to NAVAIR 

 50-30GMQ-29-1 for guidance in mechanical 

 maintenance, minimum performance checks, and 

 symptom troubleshooting. 



RAIN GAGES 



Precipitation measurements are made from 

 samples caught in gages, or from samples taken 

 from representative areas when the catch of 

 solid forms in the gage is not representative. 



FOUR (4) INCH GAGE 



The nonrecording plastic rain gage consists 

 of a 4-inch diameter collector ring and 



66 



