260 



THE BELL SYSTEM TECHNICAL JOURNAL, JANUARY 1957 



DESIGN OF INTERNAL UNIT OF SUBMERGED EQUALIZER 



The submerged equalizer corrects for the difference between the as- 

 sumed design cable characteristic and the subsequently determined laid 

 characteristic for equal attenuation lengths at 552 kc. It also absorbs 

 the loss of 9 nautical miles of cable and has an attenuation of 26.0 db 

 at 552 kc. 



The construction is identical with the submerged repeater except for 

 the replacement of all can assemblies, other than the power filters, by 

 the equalizer cans. Fig. 7 is a schematic of the unit. 



ELECTRICAL COMPONENTS 



General 



The components used in the repeaters were either designed specially 

 for submerged repeaters or were standard items with improvements. 

 There are approximately 300 components in each repeater of which 110 

 are in the amplifier. Rigorous control of manufacture and meticulous 

 inspection is imperative to ensure a consistent long-life product, and 

 cleanliness is essential at all stages. In some cases 'belt and braces' tech- 



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MOISTURE DETECTOR 

 FOR HOUSING 



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Fig. 7 — Schematic of submerged equalizer. 



