ephone systems?

2. What are the common arguments against these systems and how are they
met?

3. Give the operations that the calling subscriber has to go through in
any one of the successful systems.

4. During calling what is happening at the central office?

5. Describe the action of the Strowger or Automatic Electric Company
selecting switch.

6. What is the function of a line switch?

7. Describe the Strowger scheme of trunking and illustrate its action by
diagram.

8. Make a diagram of the sub-station apparatus and connections.

9. Make a diagram of the line switch unit.

10. Describe the action of the various guarding features necessary to
protect a busy line.

11. Make a simple diagram of the circuits of the first selector.

12. Give the functions and operations of the connector.

13. Give a diagram of connecting circuits.

14. Tell all you can regarding the battery supply to the connected
subscriber.

15. How are subscribers disconnected after they are through talking?

16. Describe a multi-office system.

17. Give a diagram of circuits of the trunk repeater.

18. Make a complete diagram of the connections between a calling and a
called subscriber in an automatic system.

19. What is the rotary connector?

20. Describe the sub-station equipment of the Lorimer automatic system.

21. Describe the Lorimer central-office apparatus.

22. Give a description of the progress of a call from its institution to
the final disconnection in the Lorimer system.

23. What is the automanual system?

24. Give general features of the operation in the automanual system.

25. Describe the automanual system subscribers' apparatus.

26. Give a description of the automanual central-office equipment.

REVIEW QUESTIONS

ON SUBJECT OF TELEPHONY

PAGES 227--270

* * * * *

1. What kinds of currents are employed?

2. What types of power plants are used?

3. Describe the sources of current supplied for the operator's
transmitter current and ringing current.

4. Make a diagram of the Warner pole changer.

5. Make a diagram of pole changers for harmonic ringing.

6. What is a multi-cyclic generator set?

7. Make a diagram of governor for harmonic ringing generators.

8. Describe the various primary sources of power.

9. Make a diagram of the mercury-arc-rectifier circuits.

10. What provision against breakdown is made?

11. Tell all you can about the sto