FLEXIBLE REPEATER DESIGN 



97 



<3 0.1 



U 



LU 



a 



z 

 o 



5 -0.1 



lU 

 D 



< 



-0.2 



20 



40 60 80 100 120 140 



FREQUENCY IN KILOCYCLES PER SECOND 



160 



180 



Fig. 19 — Repeater deviation from 36.9 NM design cable. 



The deviation of the insertion gain of the repeater from the loss of 

 36.9 nautical miles of design cable^ at sea bottom is shown in Fig, 19. 

 This is well within the objective of =t0.05 db. 



It has been pointed out that the repeater input and output impedance 

 do not match the cable impedance. This results in ripples in the system 

 frequency characteristic due to reflections at the repeater. These are 

 shown in Fig. 20. 



The noise performance of the repeater is determined by the input tube 

 and the voltage ratio of the input coupling network. Amplifier noise 

 referred to the input is shown in Fig. 21. At the upper frequencies the 



10 



15 



20 



25 30 35 40 45 



FREQUENCY IN KILOCYCLES PER SECOND 



65 60 



Fig. 20 — Interaction ripple for TAG sj'stem. 



