Broadcasting (Oct 1931-Dec 1932)

Lieut. E. K. Jett Gerald C. Gross ieallocate Non-Broadcast Band Feb. 1 Television Needs Anticipated in General Realignment of Communication Frequencies; Channels Doubled SWEEPING reallocation of the i|Dle radio spectrum, excluding broadcast band, takes place on b. 1, effecting a reduction in nnel widths which practically 1 double the number of available quencies by raising operating pdards to the level of modern Ho technique. Covering all commercial and ex imental communication stations, shift was devised by the Fed 1 Radio Commission's engineerdivision at a series of round le conferences with licensees r a period of more than a year. t a single hearing was held, and atever difficulties were encoun ed in the frequency exchanges ong different classes of services er got beyond the closed doors the engineering division, yet the ire reallocation met with the isfaction of all parties conned. "he reallocation, which is in acd with the recommendations of International Technical Conting Committee on Radio Comnications that met at The Hague 1929, was approved by the Com5sion last Sept. 3. ncorporated in the Commisn's new rules and regulations, reallocation places into effect the first time a one-tenth per t separation between frequen5 above 1,500 kc. — the upper ex,mity of the broadcast band, — as iinst the present standard of 0 tenths per cent. The number channels available from 10 to 300 kc. is consequently increased m 1,814 to 3,025. -Vhile the shift has no direct .ring on broadcasting, it does :icipate the prospective needs of svision. Provision is made for iew sound track (1550 kc.) just side the broadcast band in place the former frequency of 1604 Definite regulations covering ual broadcasting are incorpord, and one frequency in the raem short wave band, heretofore igned for experimental teleion, is exchanged for another in ■■ lower portion of the same band, :viously assigned to aviation in ler to bring the television band o closer proximity with the ■adcast band. Commission's Best Work 1 ILED by Maj. Gen. C. McK. Itzman, chairman of the Comssion, as "probably the most imrtant and satisfactory job yet tie by the Radio Commission," ! realignment was worked out ier the supervision of Dr. C. B. liffe, Commission chief engineer. e detailed work was accomshed by Lieut. E. K. Jett, U. S. retired, assistant chief engipr. The international communiions and television aspect were ndled by Gerald C. Gross, chief the international and inter-dertmental relations section. Commenting on the undertaking, airman Saltzman emphasized at it was all arranged at a con'ence table. "It never could ve been done by hearings and y suits," he asserted. Dr. Jol"e declared that unless there are unforeseen developments the entire project will become operative as scheduled on Feb. 1. Lieut. Jett explained that enforcement of the order necessitated a thorough revamping of allocations of frequencies to particular types of service, such as pointto-point, coastal, marine relay, ship, aeronautical, television, geophysical and experimental assignments. Tolerance limits to minimize interference are prescribed for the various classes of service. Of significance is the fact that the new alignment extends the limits of the usable portion of the high frequency range from 23,000 to 28,000 kc, making available 175 additional frequencies on the onetenth per cent separation. Heretofore 23,000 kc. has been recognized as the extremity of the reserved portion of the spectrum, under the international treaty adopted at the Radiotelegraph Conference held in Washington in 1927. Designation of 1550 kc. as the new television sound-track was agreed upon because it is adjacent to the broadcast band. That means, according to Lieut. Jett, that most broadcast receivers will pick up voice modulation; and thus the need for special short-wave receivers to receive the short wave voice accompaniment to television will be obviated. Moreover, it was pointed out that allowance is made for the 50-kc. separation deemed necessary between broadcast channels in the same locality to avoid cross-talk. Exchange With Aviation BY MUTUAL agreement between aviation and television licensees, the band from 2,850 to 2,950 kc. was exchanged for the 1,600-1,700 kc. band, the latter heretofore having been assigned to aviation. Thus, the new sound track channel of 1,550 kc. is adjacent to the new television band, and the sound track channel, in turn, is adjacent to the broadcast band. Other details of visual broadcasting regulations were contained in the Dec. 15 issue of Broadcasting. These, together with such other shifts and regulations of particular interest to broadcasters, such as relay broadcasting and general experimental operations, are incorporated in newly printed rules and regulations just forwarded to licensees by the Commission. In the frequency range from 10 to 1,500 kc, covering fixed, government, maritime, state police, aircraft and broadcast service, the number of channels, under the new allocations, is increased from 561 to 674. In the bands from 1,500 to 6,000 kc, relating to fixed, government, maritime, municipal police, television, experimental, amateur, aviation, general communication and miscellaneous services, the number of frequencies is increased from 639 to 947 under the onetenth per cent separation. The largest increase occurs in the high frequency range from 6,000 to 28,000 kc, covering the transoceanic services, ship telegraph and telephone, government, aviation, amateur, experimental relay broadcasting and unreserved facilities. This increase is from 624 channels on the two-tenths per cent separation, to 1,377 on the onetenth per cent, taking into consideration also the increased range of the band from 23,000 to 28,000 kc. Assignments, tolerances, and widths of frequencies below 550 kc, or in the low and medium bands, have been designated in the new order from the operations standpoint. Band widths required in the different ranges have been selected, and a channeling system has been worked out to meet these requirements. Differences in the characteristics of the frequencies are responsible for these provisions. System is Flexible THE IMPORTANCE of frequency stability is stressed in the regulations, which details a comprehen sive list of requirements as to tolerances for the different classes of stations, all representing a "tightening up" of requirements. It is brought out that nations signatory to The Hague conference agreed that modern apparatus and up-to-date methods must be employed if the narrower separation is to be accomplished without interference. The entire system has been so devised as to make it extremely flexible. As the art progresses, and upon substantial proof that no interference will be caused, the number of stations assigned to the various frequencies may be augmented. The rigid channeling system heretofore enforced, in effect, is discarded, but the allocations always are protected by the requirement that a proper showing of technical advancement must be made before changes will be permitted. To prepare for the simultaneous shift, the Commission last September adopted an order extending all existing licenses for the various classes of service until 3 a. m., Feb. 1. New licenses issued since then have been in accord with the new allocations. It is expected that all licenses affected will clear through the Commission prior to Feb. 1, and will be issued under the new service and station classifications covered in the rules and regulations. The Commission, on Jan. 5, decided to waive for one year only, to put into effect the staggering system, the requirements of the new rules and regulations with respect to these classes of stations, so that licenses for these stations may be renewed for a longer period than one year. This action was taken so that the Commission and licensees will be relieved of the necessity of handling short term licenses, and at the same time to permit the issuance of licenses in accordance with the schedule of normal expiration dates. The license period of each class of station is as follows : Aeronautical, aeronautical point to point and airport license periods from Feb. 1, 1932, to March 1, 1933. Aircraft license period from Feb. 1, 1932, to April 1, 1933. Municipal police, state police, marine fire, experimental visual broadcast, (including synchronized sound track stations) experimental relay broadcast and special emergency license periods from Feb. 1, 1932, to May 1, 1933. All classes of stations in Alaska, with the exception of broadcast and amateur, license periods from Feb. 1, 1932, to June 1, 1933. Stations of other classes will be issued licenses so as to expire in less than one year on the regular date approved for each particular class of station. These stations will receive licenses ranging in time from eight months to one year. Monthly Rate Cards REVISED monthly rate cards are being mailed regularly to advertisers and agencies by WPTF, Raleigh, N. C, according to H. K. Carpenter, manager. Included in the rate cards, is an "open time" listing, showing what time is available for sponsorship on the station. inuary 15, 1932 • BROADCASTING Page 13