M. G O ETZ 



CHAPTER 13 



MECHANICAL DESIGN AND PACKAGING* 



The preceding chapters have discussed the principles of airborne radar 

 system design from the points of view determined by system requirements, 

 by electromagnetic wave propagation, and by electronic considerations. 

 The thorough application of these principles to a problem should result in 

 development of a sound system concept and suitable circuits. The reduction 

 of these concepts and circuits from diagrams on paper and from breadboards 

 in a laboratory to a production radar set requires a large amount of engi- 

 neering effort, much of which is mechanical in nature. The major portion of 

 this mechanical engineering work is devoted to the many phases of what is 

 commonly called "electronic packaging." Given good circuit design, the 

 reliability of a system is controlled in large part by the quality of its 

 packaging. 



The term packaging, as used here, refers to the selection, mounting, 

 assembly, and interconnection of the component parts of an airborne radar 

 for its required service. Packaging design usually includes at least the 

 design of a chassis supporting the components and of protection from some 

 of the other environmental factors. (The design of the antenna mount, 

 especially for a tracking radar, is a separate major project in machine 

 design, not normally considered as packaging.) Among the major influences 

 upon this phase of design are the following. 



1. Circuit requirements 



2. Space and weight limitations 



3. Environment 



4. Necessity for maintenance and ease of installation 



5. Transportation and supply 



6. Flexibility 



7. Reliability 



8. Economy of manufacture 



The mechanical design of any electronic package is primarily determined 

 by the circuit requirements, such as the number and type of components. 

 While this factor must be included foremost in a list of factors influencing 



*Paragraphs 13-1 through 13-14 are by R. M. Sando and J. W. Titus. Paragraph 13-15 is 

 by M. Goetz. 



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