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BELL SYSTEM TECHNICAL JOURNAL 



transit case must be capable of submergence under water without ill effects. 

 Fungus-proofing with a fungicidal lacquer is a standard requirement. 



Simplicity, Reliability, Accessibility 



Not only must the functioning of the test set be reliable, stable and trou- 

 ble-free, but the set must make minimum demands for special skill or tech- 



Fig. 3 — Portable units used in checking airhoriu' radars al Hnca Raton, Fla. 



nique on the part of the maintenance man. Access for maintenance pur- 

 poses, while important in radar test sets, is not as controlling as in the radars 

 themselves and sometimes has to be sacrificed in part for compactness. 



Ruggedness 



For general application, the test equipm.ent must be capable of with- 

 standing airplane vibration, the shock of hea\y guns, depth charges and 



