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BELL SYSTEM TECH MCA L JOURNAL 



envelope and certain ceramic details of the tube, the above measurements 

 would give complete information regarding the circuit. Certain losses have 

 been found, however. These are measured as follows: At the time when 

 terminals .vo are shorted a standing wave measurement is made in the wave- 



cox IZ^ 



Ax 

 Fig. 5 — Typical cotangent-cotangent plot. 



guide line at the left. From this measurement and the cot-cot data it is 

 possible to compute an equivalent resistance in series with the gap caused by 

 losses present in the circuit. This equivalent series resistance is given by 



R.= 



SWR 



(5) 



