426 



TECE BELL SYSTEM TECHNICAL JOURNAL, APRIL 1951 



facture. The complete thermistor illustrated in Fig. 6 has less than one- 

 third the volume of the corresponding thermistor used in the earlier K2 

 carrier system and as a result of design refinements will operate on less 

 transmission power. 



Fig. 6 — Thermistor assembly used for gain regulation of repeater and group amplifiers 



Filters and Equalizers 



Filter and equalizer assemblies required in any system usually are the 

 largest apparatus items and they vary considerably in size due to the dif- 

 ferences in the type and number of circuit components needed to provide 

 the desired performance characteristics. Although smaller components shrink 

 the dimensions of these assemblies correspondingly, they are still incompat- 

 ible with the dimensions of other apparatus items. It was decided, after 

 study of the different circuit configurations and circuit elements needed 

 for the N-1 System, to divide up the more compUcated networks for as- 



