LEIDOS CYBER, INC.

TELTONE

ELECTRICAL DEVICES FOR USE IN OR WITH TELEPHONE AND SIMILAR COMMUNICATION SYSTEMS-NAMELY, [ TOUCH DIAL TEST SETS, ] MULTI-FREQUENCY RECEIVERS FOR USE IN TOUCH TELEPHONE NETWORKS AND OTHER M.F. SYSTEMS AND TO EXPAND AN EXISTING MULTI-STATION KEY INTERCOM SYSTEM TO A LARGER NUMBER OF STATIONS, A LEICH PABX CONVERSION SET FOR PRIVATE AUTOMATIC TELEPHONE EXCHANGE SYSTEMS TO PERMIT PROCESSING EITHER A TOUCH OR ROTARY DIAL CALL, AND INTERCOM SYSTEM FOR USE WITH TOUCH DIAL OR COMBINATION TOUCH DIAL TELEPHONE SYSTEMS, [ A GROUND-TO-LOOP START CONVERTER FOR USE ON TELEPHONE PABX LINES SO AS TO PERMIT DIALING LOCALLY WITHOUT GOING THROUGH OUTSIDE TRUNKS, ] AND A VOICE-OPERATED ELECTRONIC SWITCHING SYSTEM OPERABLE TO DISTINGUISH BETWEEN VOICE SIGNALS AND CALL SIGNALS IN ORDER TO DETERMINE LINE USAGE;