7-A2 rotary automatic system. III

For previous sections of this paper [see Abstracts 1933B02078 and 1933B02843]. The present instalment deals with the subscriber's line and line-finder circuit, the first group selector circuit and the register circuit. The detailed operations of the circuits are not described, but rather the features and the working limits of lines, junctions, and dial speed. All circuits are designed for 48-V operation with a permissible variation of 44-52 V. Routine and testing facilities are dealt with.