482 BELL SYSTEM TECHNICAL JOURNAL 



United Nations forces. The production rate at the end of the war exceeded 

 5,000 test sets a month. In numerous cases, moreover, small preproduction 

 quantities of test equipment were built on a "crash" basis for special mis- 

 sions and for training purposes. The test equipment produced for the field 

 had to be more precise than the radars, and the equipment used in the factory 

 and laboratory to test the field test equipment had to be still more precise. 

 Trends of development at war's end were toward (a) further broad-band- 

 ing, simplification and precising, and (b) coverage of new frequency ranges. 



References 



(1) "Ultra-High Frequency Techniques," by J. G. Brainard, G. Koehler, H. J. Reich, 



and L. F. Woodruff, D. Van Nostrand, 1942. 



(2) "Reflex Oscillators," by J. R. Pierce, Proc. LR.E., Vol. 33, Feb. 1945, p. 112. 



(3) "The Lighthouse Tube," by E. D. McArthur and E. F. Peterson, Proceedings of 



National Electronics Conference, Vol. I, 1944, p. 38. 



(4) "Electromagnetic Waves," by S. A. Schelkunoff, D. Van Nostrand, 1943. 



(5) "The Proportioning of Shielded Circuits," by E. I. Green, F. A. Leibe and H. E. 



Curtis, Bell System Technical Journal, Vol. 15, April 1936, p. 248. 



(6) "Resonant Lines in Radio Circuits," by F. E. Terman, Electrical Engineering, Vol. 



53, July 1934, p. 1046. 



(7) "Ultra- Short-Wave Transmission Phenomena," by C. R. Englund, H. T. Crawford, 



and W. W. INIumford, Bell System Technical Journal, Vol. 14, July 1935, p. 369. 



(8) "Thermistors in Electronic Circuits," by R. R. Batcher, Electronic Industries, Vol. 



4, Jan. 1945, p. 76. 



(9) "An Impedance Transmission Line Calculator," by P. H. Smith, Electronics, Jan. 



1944. 



(10) "Microwave Transmission," by J. C. Slater, McGraw-Hill, 1942. 



(11) "Theory of the Electromagnetic Horn," by W. L. Barrow and L. J. Chu, Proc. I.R.E., 



Vol. 27, Jan. 1939, p. 51. 



(12) "Attenuation of Electromagnetic Fields in Pipes Smaller Than Critical Size," by 



E. G. Lindner, Proc. I.R.E., Vol. 30, Dec. 1942, p. 554. 



