REPEATER DESIGN — NEWFOUNDLAND-NOVA SCOTIA LINKS 



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ORIGINAL BRITISH 



POST OFFICE 

 MODEL REPEATER 



50 100 )50 200 250 300 350 400 450 500 550 600 



FREQUENCY IN KILOCYCLES PER SECOND 



Fig. 17 — Repeater-gain response. 



PERFORMANCE 



The gains and losses of various sections of the repeater are shown in 

 Fig. 13. Figs. 14 and 15 show, respectively, the harmonic distortion and 

 the stabilit}^ characteristics of the amphfier with one and two paths 

 operating. The total shunt loss across the amplifier is shown in Fig. 16 

 as a margin above the amplifier gain. The curves show the result with 

 55-ohm terminations on the repeater and with a short-circuit on each 

 terminal. Fig. 17 shows the production spread in gain of the 16 repeaters 

 for the system as a deviation from the target value. The highest standard 

 deviation (at 260 kc) was only 0.11 db. In all respects the production 

 repeaters proved to be very consistent and satisfactory in their per- 

 formance and differed httle from the original laboratory-built model. 



Typical electrical characteristics of a repeater and the submerged 

 equalizer are showTi in Appendices 1 and 2 respectivel3\ 



The characteristics of the completed link are described elsewhere,^ 

 but it is of interest to note that the overall tests showed that the link 

 behaved as predicted and met the noise requirement and the design 

 margins. 



ACKNOWLEDGMENTS 



It will be appreciated that the design and manufacture of these re- 

 peaters has been an undertaking of teams rather than of individuals. 

 The authors are very grateful to Standard Telephones and Cables, Ltd., 



