The Communications Technician O 3&2 was written for enlisted personnel of the United States Navy and Naval Reserve whose duties required them to have a knowledge of the fundamentals of communications. The primary objective of this Rate Training Manual (RTM) was to enhance the degree of effectiveness and quality of communications.
This RTM provided a summarization of the various functions of communications and the processes that supported those functions. The opening chapters provided general information concerning the CTO rating, security and organization. This was followed by a study of communication theory which includes a discussion of modulation, the frequency spectrum, communication links, transmission systems, and wave propagation. This coverage was very helpful to the reader since message traffic flow is dependent upon the quality of circuits and equipments provided.
You will note a broad area of this manual describes message preparation and formats. Although large numbers of messages are processed, transmitted and received via sophisticated automated equipments, the key to the system is the care with which you prepare the message.
Those who work in communications know how frequently procedures and publications change. This RTM was up to date when published (1975), and it will, from time to time, be revised.

GUARDIAN OF OUR COUNTRY
The United States Navy is responsible for maintaining control of the sea and is a ready force on watch at home and overseas, capable of strong action to preserve the peace or of instant offensive action to win a war.
It is upon the maintenance of this control that our country’s glorious future depends; the United States Navy exists to make it so.
WE SERVE WITH HONOR
Tradition, valor and victory are the Navy’s heritage from the past. To these may be added dedication, discipline and vigilance as the watchwords of the present and the future.
At home or on distant stations, we serve with pride, confident in the respect of our country, our shipmates, and our families.
Our responsibilities sober us; our adversities strengthen us.
Service to God and Country is our special privilege. We serve with honor.
THE FUTURE OF THE NAVY
The Navy will always employ new weapons, new techniques, and greater power to protect and defend the United States on the sea, under the sea, and in the air.
Now and in the future, control of the sea gives the United States her greatest advantage for the maintenance of peace and for victory in war.
Mobility, surprise, dispersal, and offensive power are the keynotes of the new Navy. The roots of the Navy lie in a strong belief in the future, in continued dedication to our tasks, and in reflection on our heritage from the past.
Never have our opportunities and our responsibilities been greater.
