The Toronto-Barrie Toll Cable * 



By M. J. AYKROYD and D. G. GEIGER 



General 



"TOURING 1937 a 60-mile toll cable was completed between Toronto 

 ^-^ and Barrie which, in several respects, is unique. Among the 

 interesting features in the design and construction of this toll cable 

 were the use of non-quadded exchange cable and loading, a 60-mile 

 repeater spacing, planning for future carrier operation, and extended 

 pole spacings. 



Prior to the installation of this toll cable, the territory to the north 

 and northwest of Toronto was served by three open-wire pole lines. 

 Figure 1 shows these lines and the territory served by them. The 

 Toronto-Owen Sound lead entering Toronto through a 7-mile entrance 

 cable was poorly located in towns and on highways, and was paralleled 

 by power lines which caused considerable noise on the longer circuits. 

 The Toronto-Collingwood and Toronto-Barrie lines, which were 

 common for some distance north of Toronto on a 6- and 5-arm lead, 

 entered Toronto through an 11-mile entrance cable which had been 

 in place about four years, and contained a number of spare conductors 

 due to its having been designed for two additional lines. 



It was realized that, if open wire were to be continued, circuit growth 

 would require a new line arranged for carrier operation and a general 

 rebuilding, rerouting and retransposing for carrier operation of the 

 existing lines. In addition, carrier operation would necessitate ex- 

 pensive carrier loading of the entrance cables at Toronto, and the 

 length of these entrance cables would limit the length of the carrier 

 circuits for operation without intermediate repeater stations. 



Studies Prior to Construction 



With large expenditures foreseen for the continuance of open wire, 

 it was only natural that a study should be made of the possibility of 

 the use of a toll cable on a basic route and the use of as much as possible 

 of the existing lines as feeders to the cable. Cost studies on an annual 

 charge basis for a twenty-year period of open wire with superimposed 

 3-channel carrier systems, and for a 2-wire 19-gauge quadded cable 



* The unusual solution of a difficult toll cable problem which is described in this 

 paper will be of interest because of its novelty rather than because of any expected 

 general application of this type of construction to toll cable routes. 



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