THROWDOWN MACHINE FOR TRAFFIC STUDIES 337 



digit number made up as follows: 



R— TLF— SW 



where R— route No. 10, 11, 12, 13 

 TLF— trunk link frame No. 0-9 

 SW— smtch No. 0-9 



Jacks representing these same incoming trunks also appear at the 

 assignment position. 



The incoming registers consist of short sleeves which can fit over the 

 trunk peg. When a call is originated by a particular trunk as indicated 

 by the time on a waiting incoming call shp, the trunk is associated with 

 the correct type of incoming register by slipping the sleeve correspond- 

 ing to the latter over the trunk peg. The peg and sleeve then accom- 

 pany the call sUp into the system. Appropriate times for each action are 

 entered on the call slip. 



The incoming register sleeves are held on arrays adjacent to the trunks. 

 They are identified by a three-digit number: 



CONN— REG 



where CONN — marker connector No. or 1 



REG— register No. 00-19 

 Waiting holes are provided at the register array for holding trunks if 

 all registers are busy. 



MARKER CONNECTOR OR GATE 



This is a bridging position between the originating position and marker 

 position! Through it must pass all call slips and pegs requiring marker 

 service. The originating operator places call sUps and pegs in the gate 

 from one side and the marker operator removes then at the other. 



The gate, shoAvn on Fig. 18, provides jacks for pegs and slots for 

 call sUps arranged in blocks corresponding to the individual marker 

 connectors for line link frames, originating registers and incoming re- 

 gisters. It is divided into two sections, a storage section in which calls 

 wait for an idle connector, and an active section in which calls wait for 

 an idle marker and removal by the marker operator. An associated 

 relay circuit controls the flow of traffic through the gate, simulating 

 actual No. 5 operation, and indicates by lamp the appropriate action. 



When a call shp is ready to enter the gate, the originating operator 

 obtains the corresponding line or register peg and places the peg and 

 slip in a jack and slot, respectively, in the correct connector block of the 



