Broadcasting (July - Sep 1950)

GE Color (Continued from page U7) jctric vice president and general nager of the GE Electronics i|pt., in a letter to FCC Chairman Byne Coy disclosed the new sys tto was evolved by Robert B. ';|me, consultant in the GE re '(\.-er division, who has been a % engineer since 1926 and has ^irked on television receivers Ice 1934 except for the war fried. Copies of his letter were ;iit to the other Commissioners. Ir. Baker said he recognized "it is tier late to submit for consideration lew system of color television. Untnnately, however, research and -'elopment cannot be scheduled, -erwise we would have presented 1 system at the recent hearing. In J? event, the . . . system . . . ap»rs to have such outstanding potenL advantages as to justify serious usideration even at such a late date." [The GE executive stated his m's system "has very important vantages both technically and jnomically." He indicated it has ii5n "critically studied by our ortiization and others" and "apars to be technically sound." s 'We have not had time to make nplete tests on this system," . Baker explained, adding, "How "3r, we have just completed tests prove what seemed to be crit;.l points." He indicated at pres,t "the major effort of our labora rt-y is directed to the developmt" of the new system. GE indicated existing standard ■mochrome TV transmitters with lie modification could transmit le frequency interlace system. It .s pointed out that because the »re complex and sensitive equipknt components were confined to (p transmitter, more reliable and ippler receivers were possible. Possible Disadvantages jSome possible disadvantages |;ed by GE for its system were: j^quirement of either more accu4;:e receiver alignment and tuning effective automatic gain control i each color; possible color fringdue to differential time delay propagation betn'een color carijr frequencies; full 4 mc band;^|dth is required for relaying in lor; possible "second-order" color .,nging due to incomplete "physio.rtical filtering" by the eye in l--wing rapidly moving objects. Physiological filtering, or the ■wer's eye's persistence of vision, s termed a second unique feare of the GE system aside from fundamental frequency intere concept. Physiological filterl is the means used for separatl the color signals transmitted interlaced "bunches" of freencies. Analysis shows that two such fresncy-interleaved signals are always . -placed from each other approxittely by an odd multiple of halt the e-scanning frequency," GE exIned. "Then if a composite of such Bals is applied to a picture tube it can be shown that their relate polarities reverse at thie usual me frequency of 30 c.p.s. Thus, [arrangements are made so that only } color-signals are applied simuleously to one picture tube grid, the Issired signal will alternately add 1 subtract from the desired signal frame frequency and its effect will essentially filtered out physiologic ally, i.e., by the persistence of vision in the viewer's eye." GE explained that with application of the two "fundamental principles of frequency interlace and 'physiological filtering', many promising forms of color television systems can be envisioned." The one suggested by GE specifies that a green signal, to which mixed highs have been added, is transmitted in the usual 4 mc bandwidth. Red and blue subcarriers are modulated respectively by red signals of 1 mc bandwidth and blue signals of 0.2 mc bandwidth, displaced from each other far enough in frequency so that red and blue can be separated by conventional filter circuits, GE pointed out. These subcarriers are so displaced with respect to the gi'een carrier (i.e. by odd multiples of half the line-scanning frequency) that they each can be divorced from green by physiological filter ing, GE told the Commission. GE noted it has been estimated that 46 '/f of the spectrum space between harmonics of the line frequency are unused. GE told FCC existing monochrome sets without modification could pick up the green signal as a black-and-white picture while GE color sets also could reproduce monochrome pictures from a standard black-and-white transmission. Ontario Censorship THE ONTARIO Motion Picture Censor Board plans a meeting this fall of all Canadian motion picture censors and those from the United States bordering on Ontario, on the problem of telecasting motion pictures. Many pictures, which have not passed the Ontario movie censors, are now being seen in Ontario homes, close to border areas, by means of TV from U.S. stations. WPIX EMPIRE UNIT To Begin Work in Sept. WPIX (TV) New York will begin construction of its $160,000 transmitter installation atop the Empire State Bldg. in September, according to Tom Howard, WPIX chief engineer supervising the project. The new installation will include an $88,500 model TT5-A transmitter, 24-element super gain TV antenna array, diplexer, monitoring and microwave relay equipment, and 13 racks for auxiliary equipment. Transmission from the new location is expected to begin within five months, Mr. Howard said. Breider Joins Ziy ART BREIDER, former sales manager of Canada Dry Bottling Co., Cincinnati, joins the sales staff of Ziv Television Programs Inc., with headquarters in Cincinnati. TV Cameras 1 ^ BALANCED TV TRIPOD (Pat. Pending) This tripod was engineered and designed expressly to meet all video camera requirements. Previous concepts of gyro and friction type design have been discarded to achieve absolute balance, effortless operation, super-smooth tilt and pan action, dependability, ruggedness and efficiency. Below : 3 wheel portable dolly with balanced TV Tripod mounted. Complete 360° pan without ragged or jerky movement is accomplished with effortless control. It is impossible to get anything but perfectly smooth pan and tilt action with the "BALANCED" TV Tripod. Quick-release pan handle adjustment locks into position desired by operator with no "ploy" between pan handle and tripod head. Tripod head mechanism is rustproof, completely enclosed, never requires adjustments, cleaning or lubrication. Builtin spirit level. Telescoping extension pan handle. Wnte for further particulars FRANK C. ZUCKER (7flm€Rfl €quipni€nT (o. ilecasting • BROADCASTING July 31, 1950 • Page 57