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BELL SYSTEM TECHNICAL JOURNAL 



Measurements and Performance. How well the requirements which 

 were set up earlier were met by the lines and the distortion-correcting 

 networks is shown in Figs. 9 and 10. The attenuation characteristics 



O o 

 to 



6 8 10 12 



KILOCYCLES 



LINE NO 2 



8 



10 



12 



KILOCYCLES 



20 



Fig. 10 — Measured envelope delay of line circuits plus equalizers 



are well within the established limits, and the phase characteristics 

 show only a single slight departure for one circuit in a very narrow 

 range of frequency. It is of interest, in view of the fact that the 

 distortion-correcting networks were designed and built before any 

 measurements were made on the lines they were to fit, that no changes 

 or adjustments were found to be necessary in the networks, in order 

 to obtain these characteristics. 



Comparison of the television images obtained from transmission 

 over the line with those obtained from transmission from one side 

 of the room to the other, showed that no difference in quality could 

 be observed. 



