Electrical World, July 21, 1910, page 139:

The  "Wireless"  Devotees  of  Chicago.

    At this time, there are estimated to be not less than 800 amateur wireless-telegraph stations in Chicago. This figure, which has been made on a conservative basis, includes the total present number of active, dormant and neglected outfits in which the interest of their generally youthful owners is at various degrees of intensity. It numbers equipment ranging from the half-inch spark-coils of beginners, up to the high-powered stations of advanced amateurs, which are in all respects equivalent to the commercial outfits. In addition to the amateurs, there are three wireless-telegraph companies having stations in Chicago--the United Wireless Telegraph Company, the Great Lakes Radio-wireless Company and the Continental Consolidated Wireless Company. The first-named concern does a commercial business with its chain of wireless stations on the shore of the Great Lakes, and with 65 vessels equipped with its apparatus.
    Amateur interest in "wireless" in Chicago finds expression in a club of 100 members, the Chicago Wireless Club, which holds meetings of an educational nature twice each month, on the second and fourth Fridays, in the Auditorium Building, Chicago. The membership of the club is limited to amateur operators who have wireless stations. The ages of the members range from 15 to 50. The purpose of the club is a double one--to provide practice in transmitting and receiving messages between members' stations, and to hold meetings at which specially skilled or experienced operators and electrical engineers address the club on subjects pertaining to "wireless."
    The Chicago club has taken into its own hands the regulation of members' interference with commercial signals, a matter which has elsewhere recently echoed even to Congress. By agreement with the commercial operators, all club members having stations of over ½-kw capacity are limited to special times for sending, during which the commercial stations and low-powered amateur stations are not at liberty to work. The "big" amateurs thus have the ether to themselves the first 15 minutes of each hour from 6 to 11 p. m., weekdays, and all day Sunday. If a low-powered operator wants to talk to one of the high-powered stations, he is instructed to wait until 20 minutes after the hour, and then to put in his message, which will be answered during the first quarter of the next hour.
    An official call list is issued by the club, to be posted in all members' stations. Besides a brief enumeration of the "wireless" rules of the road and suggestions for improved transmission, the list gives the name of each member with his assigned call, consisting of two letters, as for example, "B G," and also his address and telephone number. Sometimes the last-named is useful for comparing notes when a detector sticks or a de-coherer slurs. Among the precepts of the "wireless" code of etiquette as promulgated by the club, are the following:
    Don't misrepresent yourself by wireless or use some one else's call. Never test your spark or "warm up" an electrolytic interrupter or adjust the vibrator of a coil without first disconnecting the aerial; it is not fair for you to monopolize the time by causing unnecessary interference. Don't interfere with commercial stations, or some day you will miss your antennae.
    Until recently, the club sent out a "wireless" bulletin each evening, as a matter of practice for amateur operators in receiving. The bulletin usually consisted of an article of some electrical or telegraphic interest, about 120 words in length, and was transmitted, in succession, from some one of the 1-kw stations or over, every evening at 8 o'clock. These messages were sent slowly, at the rate of about 10 words per minute, and could be received all over the city. Sometimes the program was varied by sending passages in foreign languages, to quicken the receiving ears of the amateur operators. This practice of sending out general bulletins has, for the time being, been discontinued, on account of other activities among the wireless amateurs.
    Several members of the club have stations of capacities up to 2 kw, the equal in power of the commercial apparatus at Chicago. The signals of these larger amateur stations are frequently received across Lake Michigan, and at a wireless-telegraph school at Valparaiso, Ind.
    Original experiments with kite antennae have been undertaken by several of the Chicago amateurs. Both the box and Eddy-tailless forms of kites have been used for supporting the aluminum aerial wire, in this way attaining a vertical height of 800 ft. or more, which considerably extends the radius of transmission of a low-powered station. The field set used for this purpose consists of a 1-in. spark-coil energized from four dry cells, the whole outfit being arranged compactly in a suit case. With this apparatus, using the aluminum kite string as the aerial, a transmission distance of 10 miles is attained.
    The officers of the Chicago Wireless Club are as follows: President, Mr. Royal C. Dickson; vice-president, Mr. John Hair; recording secretary, Mr. Selden Stebbins, and corresponding secretary, Mr. Ed. M. Muellner.