r?

26. Define _trunking efficiency_.

27. Enumerate some of the elements upon which the quality of service in
a manual system depends.

28. What is team work?

29. How does the cost of telephone service vary?

30. What two general methods of charging for telephone service are in
use?

31. Describe a calculagraph and how is it used?

32. How are toll connections timed by the Monarch Telephone Company?

33. Sketch and describe the Western Electric Company line circuit and
service meter.

REVIEW QUESTIONS

ON THE SUBJECT OF TELEPHONY

PAGES 321--358

* * * * *

1. Describe a phantom circuit with diagram.

2. Explain how two phantoms may be joined by a physical circuit.

3. Which are the better, phantom or physical circuits, and why?

4. Explain how the simplex circuit differs from the phantom telephone
circuit.

5. Why are not telegraph wires as serviceable for telephone work as
telephone wires are for telegraph work?

6. Give the names of the different parts of a railway composite set and
explain method of operating.

7. State the causes of the introduction of the telephone into the train
dispatching field and explain the advantages it has over the telegraph
for this work.

8. In transmitting orders for train dispatching, how are mistakes
avoided?

9. Describe the Western Electric selector and explain its use.

10. In what way does the Gill selector differ from the Western Electric?

11. What special feature does the multiple coil selector possess?

12. What special arrangement is provided for the train dispatcher in
noisy locations?

13. How can a man on a wrecking train get connection with the train
dispatcher?

14. What is the usual limit in length of a telephone train dispatching
circuit and what is the largest number of stations at present existing
on such a circuit?

15. What is the voltage of the sending battery for a train dispatcher's
circuit and upon what is it dependent?

16. For what purpose is a repeater circuit used?

17. How is the noise caused by a high voltage battery absorbed so that
the dispatcher may talk and signal simultaneously?

18. Draw a diagram showing the circuit arrangement for the dispatcher's
outfit of the Gill system.

19. Explain fully the purpose of the retardation coil in connection with
a waystation set.

20. In case of accident to a train wire between two stations, how can
the connection be patched if th