The Radio League of America was intended for all non-professionals interested in radio, whether sending or receiving. Thus, of the "300,000 U.S. amateurs" this review talks about, the vast majority only had receivers. It wasn't until around 1920 that "radio amateurs" would generally come to mean only individuals which had their own private transmitters. The League had a close affiliation with the U.S. Navy, given that the war in Europe had broken out a year earlier, and eventual U.S. involvement in the conflict was seen as very likely.
 
The Electrical Experimenter, December, 1915, page 381-384:
RLA logo
A  Retrospect.
DURING the past year the need of a national body to champion the cause of the wireless amateurs in the United States has become more and more pressing. There are now over 300,000 radio amateurs and about 350 local clubs in existence in the United States, but there is no national body to safeguard the interests of the amateurs.
    When H. Gernsback, in 1909, organized the Wireless Association of America, there did not exist at that time a wireless club in the United States. There were then, of course, numerous radio amateurs in this country, but the wireless art--as far as the amateur was concerned--was only in its earliest infancy. Mr. Gernsback, who at that time sensed approaching danger to the wireless amateurs in the form of hostile legislation, succeeded in banding together the majority of wireless enthusiasts, and the membership of the association grew rapidly till at the end of 1912 there had been enrolled no less than 22,300 members,
    In those early days the wireless amateurs in this country were a rather reckless sort of element and became more and more disliked on account of their growing mischief. False distress and alarm calls by perverted "humorists" were the usual "smart" acts, and when a coastal station received a C.Q.D. call in those days the thought was always uppermost in the operator's mind that the call was one of the usual amateur hoaxes. Despite Mr. Gernsback's vigorous warnings through his editorials in Modern Electrics, of which publication he was editor, the mischief continued, till in 1910 several bills were introduced in Washington which fairly promised to throttle the activities of every wireless enthusiast in the country.
    This, of course, brought the amateurs to their senses speedily, but had it not been for the formation of the Wireless Association of America a year earlier, all efforts would have been in vain and the amateur would to-day be as dead an issue as he is at present in Europe. Through the Association Mr. Gernsback caused thousands of letters to be written to Washington officials by the wireless amateurs, and he furthermore succeeded in enlisting the press of the country in taking up the cry to save the amateurs from hostile legislation. All this had the desired effect, and when finally in 1913 the Alexander Wireless bill, amended, was signed by President Taft, thereby becoming law it contained almost word for word Mr. Gernsback's historical recommendation of his editorial in the February 1912, issue of Modern Electrics. As is well known, that editorial called the attention to the lawmakers that in case the amateurs were to be restricted the latter should be allowed to operate their stations at a wave length below 200 meters, and they should furthermore be allowed the use of power up to one kilowatt. This suggestion saved the day, and the amateur at last had come into his own,
    With the passing of the wireless act in 1913 the usefulness of the Wireless Association of America had come to an end, and thus matters rested.

A  Formidable  Defense  Weapon.
THE advent of the great European war in 1914 found the United States in an unprepared condition as regards its defenses and vigorous steps were promptly taken to wake us up from our lethargy. President Wilson's recommendation to the country for a vast increase of our army and navy has been so much discussed of late that no further reference to his valuable advice is required here. It suffices to say that probably a vast majority of citizens indorse the President's defensive military program. RLA Application
    But there exists to-day a formidable defense weapon, which up to now has not been exploited by Uncle Sam. We refer to the thousands of amateur radio stations scattered broadcast through the entire length and breadth of this fair land. There is hardly a hamlet today which does not boast of several amateur wireless stations, and their number is increasing by many hundreds each day.
    As the European war has so thoroughly demonstrated quick transmission of intelligence is of paramount importance. Telegraph and telephone lines are put out of order with ridiculously small effort by the enemy and whole sections of country are thereby isolated. Such sections are then helpless and no important messages can be safely transmitted in either direction. All this helps the enemy enormously, and the thus isolated section is then entirely at his mercy. If France or Belgium had possessed an effective amateur wireless scout service there might possibly be a different story to tell to-day. In these days of fast military movements, quick reporting of war intelligence is of incalculable importance, and if this is true of Europe, it is even truer in the United States, the country of such vast and undefended coast lines.
    One needs not be a dreamer in order to appreciate how easily a hostile fleet could approach our long, badly patrolled coasts and try a landing of an armed force. There might not be a telegraph or telephone line around for miles, or if it did exist, it is certain that spies operating on land would have found little trouble in putting it out of commission beforehand.
    But there will be a lone radio amateur on the alert who has seen the approaching fleet and within 30 seconds Washington will have the priceless intelligence. Vice versa, there might be a handful of poorly equipped United States militia holding the enemy at bay temporarily. It is conceivable that this small body of men might have neither sending nor receiving radio apparatus. Somewhere back of the hills the United States regulars are coming to the rescue of the sorely pressed militia men. They want the latter to hold out for a few short hours and want to tell them of their coming. The radio message containing this intelligence is flashed over the hills, but is not received by the exhausted men. However, just as all hope is given up, a lad of 17 years with streaming hair runs up to the major of the small band and breathlessly conveys the cheering news to him. He caught the message over his pitiful 30-foot aerial on top of his barn, but it saved the day. He did not even have a sending station. His outfit comprised only a cheap home-made receiving "set"! But it did the work, just the same.
    Such occasions are almost certain to arise in the future, and it is thus of the utmost importance that every patriotic radio amateur should offer his station to his country.

The  Duty  of  the  Amateur.
IF Uncle Sam grants the amateur the free use of the ether it is certainly up to the amateur to give something in return for the privilege. It was with this thought uppermost in his mind that Mr. Gernsback in July, 1915, first conceived the idea of organizing the Radio League of America. By referring to the 1915 Government book, Radio Stations of the United States, it will be seen that only 3,723 amateurs have been licensed since 1913. The reason for this surprisingly small registration is found in the fact that the law does not require receiving stations to be licensed, nor small sending stations located in the interior of large States, where the effect of a weak spark coil would not extend over the State borders. Such stations are exceedingly numerous and have been estimated to run above 300,000. Now, then, there appears no reason for doubt that sooner or later the Government would pass a new law requiring the registration and licensing of such stations in order to have such stations available in case of national stress.
    No one can foretell what surprises such a new law will bring the amateurs, and for that reason it cannot be denied that it is far better and more patriotic to give this necessary information voluntarily to the Government, instead of waiting till a new law is passed which might perhaps be detrimental from the viewpoint of the amateur.

The  League's  Charter.
THE Radio League of America was organized at New York under the laws of the State of New York in October, 1915. Its charter follows:
CERTIFICATE  OF  INCORPORATION  OF  THE  RADIO  LEAGUE  OF  AMERICA,  INC.

State of New York
City of New York      }ss.:
County of New York.

    We, The Undersigned, of full age, citizens of the United States, a majority of whom are citizens of the State of New York and resident therein, being desirous of associating ourselves together for our mutual welfare and advancement, as hereinafter is more particularly described, pursuant to and in conformity with Chapter Forty (40) of the Laws of 1909 and known as the Membership Corporations Law, do hereby certify and declare as follows:
    First--That the name by which the said corporation hereby to be formed shall be known and distinguished is and shall be Radio League of America, Inc.
    Second--That the purposes for which the corporation is to be formed are as follows:
    To promote the art of amateur wireless telegraphy and telephony in the United States among the members of the said corporation; to have available for the Government of the United States or any of its officials a complete list of all the amateur radio stations in the country pledged to the service of the Government for use in times of national danger or need; to establish a uniformity in the transmission of wireless messages by amateurs; to uphold the provisions of a law known as the Wireless Act of 1912 and all subsequent laws pertaining to wireless telegraphy to assist the Government of the United States or any of its officials in apprehending offenders thereof; to prevent the sending of misleading wireless messages; to give information to the members of the said corporation concerning new and useful devices in the operation of wireless telegraphy and telephony and to provide an organization for the interchange of ideas concerning wireless telegraphy and telephony for the benefit of the members and the public at large.
    Third--That the number of directors of the said corporation shall be and are five (5) in number; and that the names and residences of such directors who shall manage its concerns until the first annual meeting are as follows: (See below.)
    Fourth--That the territory in which the operations of the corporation are to be principally conducted is the entire United States, and that its principal office shall be and is located in the Borough of Manhattan, City, County and State of New York.
    Fifth--That the said corporation shall hold its annual meetings on the first Monday in October in each and every year beginning with the year 1916 (October 2, 1916), and annually thereafter.
    In Witness Whereof we have made and signed this certificate in duplicate and have hereunto set our hands and seals this 25th day of October, 1915.
    Hugo Gernsback, Sidney Gernsback, Milton Hymes, Harry W. Secor, Frederick H. Pruden.
    As will be seen, the League is a purely scientific organization. There are no dues, no membership fees to be paid. It has been organized under the auspices of the world's greatest wireless men, who thoroughly indorse its principles. It is not a money making organization, nor is it conducted by a commercial wireless company for its benefit.
    The Electrical Experimenter has been selected as the league's official organ, as this journal, with the largest circulation of any wireless publication at present, reaches either directly or indirectly almost every wireless amateur in the country to-day. It will publish the league's news from month to month, thereby keeping up the interest of its members.

The  League's  Rules.
EVERY wireless amateur of good standing, whether he has a sending or a receiving station, is eligible for membership. There are but two conditions:
    1. He must be a citizen of the United States.
    2. He must own either a sending or receiving station, or both.
    Each member will be supplied with an official membership certificate furnished free by the Radio League of America. Our illustration gives a good idea of this beautiful certificate, but it must be seen to be fully appreciated. It is lithographed on a heavy bond paper in green and gold, and its size is 15x11¼ inches. The text follows:
CERTIFICATE  OF  MEMBERSHIP  TO  THE  RADIO  LEAGUE  OF  AMERICA.
A membership organization organized under laws of State of New York.

    I, the undersigned, a radio amateur, do hereby apply for membership in the Radio League of America, upon the express condition that by so doing I do not assume or incur any liability either for dues, assessments or any financial obligations whatsoever, and, if accepted, I do agree to follow and abide by the rules and regulations the league as set forth herein, and all other rules and regulations which may hereafter be adopted.
    Rule 1. To observe all rules and regulations of the Wireless Act of 1912 (as set forth on the back of this certificate).
    Rule 2. That I will at all times have my station in readiness and at the service of the United States Government for use in any defensive or offensive purpose in periods of war, riot or disaster.
    Rule 3. That I will at all times allow my station and equipment to be used by the United States Government or any of its officials, and will assist, if possible, in apprehending offenders violating the Wireless Act.
    Rule 4. I furthermore solemnly and distinctly pledge myself not to send out at any time whatsoever, a misleading call, particularly a distress call (S.O.S. ...---...) nor knowingly allow another to use my station for sending out such a call.
    Rule 5. That I will at all times, in case of necessity transmit a distress call to the nearest official, either by wireless, by wire, or in person, and that I will do everything in my power to bring assistance to the party or parties thus in danger.
    Rule 6. That I will communicate to the League such information concerning the operation and construction of my radio station as will be helpful or instructive to the other members of the League.
    Rule 7. That I will, when requested, furnish information concerning my radio station and observations, which information is to be used by the League in its compilation of wireless statistics.
    Rule 8. That I will carefully read and adopt any suggestions published by the League for the benefit of its members, and the transmission of wireless communications.
    Rule 9. That in case of my removal to another address, or in case of the permanent discontinuance of my station, I will immediately communicate such facts to the manager of the Radio League of America.
    Rule 10. That I will display my membership certificate in the League in a conspicuous place in my radio station.
    In witness whereof I have signed my name and address, etc.
    Each certificate is numbered and a member is entitled to one membership certificate only. Before the League can furnish a certificate it is necessary that the prospective member shall fill out an application for membership ; a convenient blank being printed below. (If it is not desirable to cut up the magazine, a blank will be promptly mailed on receipt of a 2c. stamp to cover necessary mail charges.)
    No blank is valid nor can it be accepted unless it is filled out properly as prescribed. Two persons must sign as witnesses to the signature and these may be two friends, or your father and your mother, or a sister and a brother, etc.
    Upon receipt of the application blank the official membership certificate will be mailed. Ten cents in stamps or in coin should be inclosed to cover mail charges, handling, as well as the heavy cardboard tube to insure safe delivery.
    Upon receipt of the membership certificate by the member it must be signed at once in ink in its proper place, and it should then be suitably framed and hung up in the station in a conspicuous place.
    It will give your station official recognition, and within the next few months the amateur who cannot produce an official membership certificate will hardly be looked upon on a par with officially recognized amateurs. He will have but little standing as a wireless amateur, for he obviously refused to pledge his station to his Government.

Privileges  of  the  League's  Members.
INASMUCH as the League has been organized for the benefit of the wireless amateur, its members are entitled to the following privileges:
    Introduction to other members.
    All members are registered on cards at the headquarters of the League. The names are filed geographically by State and town. Let us suppose you live in Plattsburg, 0., and that you own a wireless receiving outfit. You very much desire to know several radio amateurs in your vicinity, but you have no means of making their acquaintance. As a member of the League you mail a letter to headquarters asking for the names of any wireless amateurs located in your vicinity. Such information will be given free to members, providing a two cent stamp is inclosed with the inquiry to cover postage. As a member of good standing in the League the other members will receive you gladly, and the future relationship between you and these members depends entirely upon yourself. Thus the League will be highly instrumental in bringing together members and cementing their friendship.

Associations  and  Clubs.
A LOCAL wireless association, or radio club, to be officially recognized by the League must have at least six members. There should be a president, a treasurer and a secretary. The address where such a body meets should be stated. Clubs and associations should meet at least once a month. The above requirements are necessary to secure publication in the Electrical Experimenter, as well as recognition in the "Radio League of America's Official Year Book."
    In this book, to be issued once a year, will be found all the important League news, a full listing of all the clubs and associations, as well as a complete list of all the members.
    The League particularly indorses and encourages the rendering of scientific lectures by their members. The latter should write scientific papers, particularly those that have a wireless subject as its theme. The president of the club should select the best paper in his opinion, and it should be sent then to the editors of the Electrical Experimenter. If it has sufficient merit it will be published in due course in the Electrical Experimenter. It will show the title of the author as well as a sub-title, giving the name of the club to which the author belongs.
    Once a year the best paper from among those that were published in the Electrical Experimenter will be selected by the editors and this prize paper will be published in the official year book. This honor will only be accorded to one paper.

Official  League  Insignia. 
AN official button securable only by the League's members is illustrated herewith. This distinctive, as well as striking, design measures ¾ inch in diameter. It is inlaid in real, hard enamel in the three national colors, red, white and blue. The aerial design as well as the mast is in gold on a dark blue background. The button is heavily gold filled and is guaranteed by the makers not to tarnish for two years. It will positively not turn brassy. You will be proud to wear one of these distinctive buttons.
    The League furnishes the button at cost ; the price, including mailing, being 20c. Both the membership certificate and the button will be sent for 25c. prepaid.
    A solid gold button as described above is furnished for $2 prepaid to those not desiring a gold filled one. The solid gold button and the membership certificate will be furnished for $2.05 prepaid, the actual cost of both.
    All communications should be addressed to
THE  RADIO  LEAGUE  OF  AMERICA,
233 Fulton Street, New York City.

NAVY  DEPARTMENT,
U. S.  NAVAL  RADIO  SERVICE,
OFFICE  OF  THE  SUPERINTENDENT,
RADIO,  VA.
H. Gernsback, Editor,
SIR:
    I beg leave to acknowledge the receipt of your letter of November 8, 1915, submitting information concerning the Radio League of America, together with a copy of the Certificate of Membership.
    It seems to me that you have undertaken to carry through a very patriotic motive in banding together the great number of amateur wireless operators in the United States, which, as you state, now number probably over 300,000 of which only about 3,000 have been licensed; it being presumed that the remainder operate receiving stations only, and under the law are not required to have licences. This latter proposition I regard as a very serious detriment to the proper government control of wireless stations, and am of the belief that legislation should provide that all stations, whether for transmitting or receiving, should be licensed by the Federal Government. Although the Radio Act provides penalties for divulging any information received by means of wireless receiving circuits, yet the fact that important government messages might be received by unscrupulous amateurs not friendly to the home government renders some form of protection necessary, and, I might add, will be advocated this coming Congress.
    The Naval Radio Service is particularly anxious to increase its operating personnel in time of public peril when many private stations, ship and shore, would probably be taken over by the general government, and the thought has arisen that through co-operation with the Radio League many of its members would like to enroll themselves for active service under the Navy Department at such times as their services might be required.
    You can readily understand that any information collected by the Radio League will be of the greatest value to this service and this office will be glad to avail itself of your kind offer to furnish such free of all cost, this to contain the names, locations, etc., of all amateurs in the United States.
    I should like further to take advantage of this opportunity to ask your co-operation in enrolling members of the Radio League for government (Navy Department) operation in time of war, and take this opportunity to enclose a circular prepared in this office which we have sent out to operating wireless companies in the United States, who in turn have distributed them to their operators, with the result that many civilian operators have engaged themselves to enlist in the Navy in time of war. Could we not do something similar to enlist members of your League, and would you lend your efforts to co-operate along these lines by giving the matter a little publicity? From the monthly list you propose to furnish we can get the names and addresses of many amateurs, among whom we might find many who would wish to enroll themselves. Of course, the forwarding letter accompanying the circular would have to be modified, but that could easily be done to call the attention of amateurs to how they can really serve their country in time of need.
    Please accept my thanks for thus being allowed to bring to your attention certain views in connection with the Radio League, an organization which can be made to be of the utmost help to the government, and by focusing the attention on existing laws bring home to every amateur the desirability of co-operation all along the line to correct the great question of interference with proper government, commercial and other legitimate correspondence handled by means of the wireless art.
               Very truly yours,
               (Signed)      W.H.G. Bullard,
                              Captain U. S. Navy,
                               Supt. Radio Service.