Welcome to RF Current, a weekly electronic newsletter focusing on Broadcast technical and F.C.C. related issues. This newsletter is part of The RF Page @ www.transmitter.com, a web site devoted to TV Broadcast RF engineering. For more information see the What is... guide to the R.F. Page site.
This page contains stories from RF Current issues published in July 1996. Links referenced in the articles were current when published but by this time may have changed. If you find a bad link, try connecting to the home page of the publication or company and look for an archive of past articles.
Andrew Corporation, in a press release issued today described its role in putting WRAL-HD, the nation's first HDTV station, on the air. Barry Cohen, Business Unit Manager, Global Broadcast Products, Andrew Corporation, said "This is a major first in Andrew Corporation's long tradition of producing quality broadcast products at the leading edge of technology". More details are available in the press release.
Today the FCC issued a news release (nrwl6036.txt) describing the new Low Power Radio Service (LPRS) it created at its July 25 open meeting. The release indicated that "LPRS devices will be authorized on a secondary, non-interference basis, for short-range, lower power communications including auditory assistance devices for persons with disabilities, health care assistance devices for persons with illnesses, law enforcement tracking systems, and point-to-point network control communications for Automated Maritime Telecommunication Systems (AMTS)." This frequency band was deemed appropriate for these low power devices because any higher power use of the spectrum could interfere with reception of TV Channel 13. To further reduce the possibility of interference to TV reception, all transmitters will have to be type accepted. The technical standards for LPRS will allow narrowband (5 KHz.), "standard band" (25 KHz.) and wide band (50 KHz.) emissions. Power will be limited to 100 milliwatts ERP. Automated Maritime Telecommunication Systems (AMTS) emissions up to 250 KHz. in bandwidth will be allowed in the upper portion of the band.
HDTV made the news after the FCC decided at today's open meeting to allocate a second TV channel to TV broadcasters for Digital TV. More technical details will be available after the FCC releases their Sixth Notice of Proposed Rulemaking. The news release (link not available - check back later) and the general news media did offer some details. First, it appears after NTSC is phased out, TV broadcasting will be limited to channels 7 through 51. The inclusion of six VHF channels should help rural broadcasters that need to reach a large area, sometimes beyond line of sight. A report on National Public Radio said the National Association of Broadcasters would oppose this final allocation plan, citing increased interference among broadcasters. The story indicated the FCC's response was that the interference would be minimal and that people who bought cable TV wouldn't even see it. RF Current will have more details on this story as more information is released.
As reported in the July 15th RF Current, the battle lines have been drawn over the proposed ATSC HDTV standard. Manufacturers and broadcasters generally support a standard, while computer companies (including Microsoft) and the Directors' Guild of America do not. The Consumer Electronics Manufacturers Association (CEMA), in a statement applauding the FCC channel allocation proposal, felt it necessary to promote the ATSC standard. The statement quoted Gary Shapiro, CEMA's president saying "The remaining challenge is to resist those who want to impose a rigid mandate and ignore flexibility by asking the FCC to only allow progressive scanning."
Supporters of the Grand Alliance ATSC standard say it is flexible and can accommodate both progressive and interlaced scanning formats, a concern of the computer industry, and that it can also accomodate a 2:1 aspect ratio, a concern of the film industry. More information on CEMA's position is available on its web site, including a copy of CEMA's Comments on the FCC's Advanced TV NPRM and a story titled Seniors Want Their HDTV.
Those opposing the ATSC standard say it is too costly, controlled by a small number of companies and is obsolete. Today a group of high tech, entertainment and consumer groups, "Americans for Better Digital TV" announced plans for "a nationwide campaign to ensure that the future of digital television is not undermined by government approval of outdated, inadequate, and expensive technical standards." The group criticized the ATSC's use of Dolby sound, calling it "outdated and inferior" as well as use of screen scanning rates that are "cumbersome and expensive to convert for computer applications". As I said in the July 15th story, the group's opinions, in spite of the high-tech connection, are poorly represented on the Web. The Americans for Better Digital TV press release listed the Director's Guild site as a source of information. The full text of the A.B.D.T. press release is available as well as a contact list. Comparing the companies supporting the ATSC standard and those against it it is an interesting exercise. Take the time to visit the sites of both sides.
Dale Cripp's HDTV Newsletter Web Site broke the news Tuesday night, announcing that WRAL-HD had begun over the air testing of the ATSC HDTV system. As reported earlier, the station is using a Harris Sigma-CD transmitter and digital ATV exciter with a special Andrew ALP series antenna. By Wednesday, the HDTV Newsletter Web Site had a copy of the Press Release announcing that "WRAL-TV today became the nation's first experimental High definition digital television (HDTV) station to go on-the-air." The Release, dated July 23rd, described the operation, saying
"The station began the transmission of full-power digital test signals today under authorization granted by the Federal Communications Commission. The new station's effective radiated power is 100 kilowatts with the antenna at 1750 feet. Full operation will follow a period of testing the Grand Alliance HDTV system as recommended to the FCC by the Advisory Committee on Advanced Television Service and as documented by the Advanced Television Systems Committee. Channel 32 will continue to make technical measurements of digital signal propagation and test coverage of the Raleigh-Durham-Fayetteville area. Signal testing will continue until Spring of 1997 when actual broadcasts of regularly-scheduled programming will begin. Television sets are expected to hit the consumer market in 1997."
For more details, see the HDTV Newsletter Web Site. Also check out Dale Cripp's HDTV editorials, articles and links of interest on the HDTV Newsletter's HDTV For Broadcasters page.
The First Report and Order and Fourth Notice of Proposed Rulemaking on LMDS and satellite services in the 28 GHz. band is now available on the Internet. Comments are due August 12th, with reply comments due August 22nd. The FCC release noted that:
With this Report and Order, we designate band segments in the 28 GHz band for several types of wireless systems, clearing the way for licensing Local Multipoint Distribution Service ("LMDS") providers, Fixed Satellite Service ("FSS") systems, and feeder links for certain Mobile Satellite Service ("MSS") systems. The associated downlink bands for satellite services are designated as well. We also adopt a Fourth Notice of Proposed Rulemaking proposing to designate an additional band segment, 31.0-31.3 GHz, for LMDS use on a primary protected basis. The Fourth Notice also seeks comment on whether the Commission should adopt eligibility or use restrictions for incumbent local exchange carriers ("LECs")and cable operators for acquisition of LMDS spectrum within their geographic service areas.
The uplink band plan is as follows:
| 27.50 - 28.35 GHz. | LMDS |
| 28.35 - 28.60 GHz. | GSO/FSS |
| 28.60 - 29.10 GHz. | NGSO/FSS |
| 29.10 - 29.25 GHz. | MSS Feeder links and LMDS (hub to sub) |
| 29.25 - 29.50 GHz. | MSS Feeder links and GSO/FSO |
| 29.50 - 30.00 GHz. | GSO/FSS |
| 31.00 - 31.30 GHz. | LMDS (proposed) |
A downlink band plan was also adopted:
| 17.70 - 18.80 GHz. | GSO/FSS |
| 18.80 - 19.30 GHz. | NGSO/FSS |
| 18.80 - 19.30 GHz. | NGSO/MSS Feeder links |
| 19.70 - 20.20 GHz. | GSO/FSS |
The abbreviations are the same as those used in the FCC release quoted above. Full technical details are available in the First Report and Order and Fourth Notice of Proposed Rulemaking.
The FCC today released its Agenda for its open meeting on Thursday, July 25th. The agenda lists two items of interest to broadcasters. One is consideration of the creation of a low power radio service in the 216-217 MHz. band, close to VHF channel 13. The other, as listed in the Agenda states "The Commission will consider issues pertaining to the allotment of channels for the Digital Television Service". No mention was made of consideration of proposals to reassign or auction existing upper UHF NTSC channels, although that conceivably could be discussed under the Digital Television topic.
Today's FCC Public Notice of Broadcast Applications included WRC-TV's filing for a CP for a new experiment station to serve Washington D.C. on Channel 27. The transmitter location is listed as 4001 Nebraska Avenue, NW, in Washington DC. Facilities requested are 500 KW ERP at 174 meters HAAT, using an Andrew ALP16M2-HSOC antenna.
Although the transmitter type was not listed, Comark Communications' web site says it will be a Comark. The Andrew antenna is from the same ALP series specified by WRAL-HD in Raleigh, NC.
In a News Release (nrwl6036.txt) issued today the FCC released details on a band plan for Local Multipoint Distribution Services (LMDS) and satellite systesm in the 28 GHz. band. In addition to 1000 MHz. of spectrum in the 27.5 to 30.0 GHz. band. the Commission added 300 MHz. of spectrum for LMDS in the 31.0 to 31.3 GHz. band. The spectrum can be used for wireless data transmission and other broadband communications services, including applications such as "Wireless Cable" video distribution, videoconferencing, telephone and Internet access.
One of the companies planning to use the frequencies allocated for satellite systems is the Teledesic Network, backed by cellular phone pioneer Craig McCaw and Microsoft Chairman Bill Gates. A news release on Business Wire from Teledesic said the company's constellation of several hundred low Earth orbit satellites "will enable affordable, worldwide access to "fiber-like" telecommunications services such as broadband Internet access, digital voice, data, videoconferencing and interactive multimedia."
AGATE, the Advanced General Aviation Transport Experiments consortium, will demonstrate its new advanced communications/navigation/surveillance(CNS)flight systems at the Atlanta Olympic Games. AGATE members include NASA, the FAA and eight general aviation companies. The system uses GPS satellite navigation to provide pilots with graphical information about their aircraft's position relative to each other and with ground based GPS units. RF links relay the data to consoles on the ground. Air traffic managers and security personnel can then monitor the location of the aircraft. The system will also be used to demonstrate "free-flight" self dispatch operations. More details are available in the NASA Press Release.
Harris' Broadcast Division today announced its intention to "establish a new research and development facility to speed the introduction of equipment for the emerging digital television market -- formerly known as HDTV." The facility, to be located in the greater Cincinnati/northern Kentucky area, will be called the "Harris Digital Television Center of Excellence". Harris will relocate staff involved with digital television (including product management, engineering, sales and marketing staff) from their Quincy headquarters to the Center. The announcement noted that "the company plans to recruit additional digital technology specialists and others to research and develop future advanced products and systems." Chester A. Massari, VP and General Manager of the Harris Broadcast Division said ""The market for digital broadcast transmission equipment and systems is growing rapidly as television stations transition from analog to digital technology. Establishing this center will enable us to build on our current technology to develop next-generation systems capable of providing even more services." Harris Corporation has played an active role in bringing digital TV to U.S. broadcasters. It developed the test bed used by the ATTC to evaluate and establish digital TV standards and has received a contract to provide digital TV transmitter equipment to the first licensed DTV station, WRAL-HD, in Raleigh, N.C.
Manufacturers and politicians are taking sides in the battle for or against the ATSC (or Grand Alliance) Digital TV standard proposed by the F.C.C. and broadcasters. The two major forces against the standard consist of computer manufacturers, represented by CICATS - the Computer Industry Coalition on Advanced Television Service - which includes companies like Microsoft, Apple and the cable TV industry, represented by the NCTA - National Cable Television Association. Other groups opposing the standard include media watchdog organizations such as the Media Access Project and the Consumer Federation of America. The motion picture industry is split, with SMPTE (the Society of Motion Picture and Television Engineers) supporting a standard and the Directors' Guild opposing it. Supporters include all major broadcast organizations, the White House Office of Science and Technology, "a senior Commerce Department technology expert" , most major TV manufacturers, including Philips / Magnavox and Sony and, according to a letter sent to the FCC last month, Congressional leaders.
Surprisingly enough, very little information on this battle is available on the Internet. Traditional government sources such as GPO yielded little information and manufacturers' sites (both computer and TV) are largely silent on this issue. The above article on the CICATS opposition was from PR Newswire, a service used to distribute Press Releases from companies and organizations. The links highlighted above will take you to either the organization's home page or news section, as appropriate. Where available, either actual text or a page with links to comments on digital TV standard was used.
According to a new study released by Ohio State University, "managers fail about half the time when they make business decisions involving their organizations." The study said "initial failures" - that is, failure to get decisions implemented, accounted for about a third of the failures. The study said "The failure rate climbed to 50 percent when the researcher considered decisions that were only partially used or that were adopted but late overturned." Decisions studied ranged from purchasing equipment to "deciding which products or services to sell". Why do decisions fail? Paul Nutt, author of the study and professor of management science at Ohio State said "Most of the good decision-making tactics are commonly known, but uncommonly practiced. Managers seem committed to fast answers and fail to recognize that quick fixes make failure likely."
For at least the last three weeks, rumors have been circulating in the broadcast industry and press about a freeze on TV station applications for new or modified facilities. The freeze was supposed to have been announced at the July 11th meeting of the Commission. This meeting was delayed to July 25th, apparently to give the Commission time to evaluate the request by some politicians to auction off TV channels 60 through 69. The reason given for the freeze is the need to have a defined environment in which to allocate digital TV channels. The FCC is expected to issue an NPRM on digital TV channel allocation in late July or August.
The FCC today issued a Declaratory Ruling and Order authorizing QAM an VSB digital transmission for MMDS and ITFS transmission. The R&O limits average digital power to a level equal to peak NTSC power. Existing analog stations must be protected from interference, although no precise frequency control (for the VSB pilot) is specifically required. Applications to modify existing analog MMDS and ITFS stations for digital will not be considered a major modification. See the Declaratory Ruling and Order for more detailed information.
General Instrument demonstrated their SURFboard cable modem working over an MMDS at the Wireless Cable Association International Exhibition in Denver, Colorado today. The unit is capable of delivering Internet at raw data rates up to 27Mbps. The system works with GI's SURFboard model SB 1000 wireless cable modem installed in a PC. GI says the system can coexist with both analog and digital video broadcast channels. The Denver demonstration was "the first wireless demonstration for data connectivity utilizing 64QAM modulation" according ot GI. More details are available in the GI Announcement. Other announcements from GI about products featured at the Denver Wireless Cable show are available on their announcements page.
In a story released yesterday, researchers announced "a fundamental advance towards the future of "colossal magnetoresistance..." In the release, Arthur Sleight, an OSU professor of chemistry, explained that "Colossal magnetoresistance is a known phenomena in which materials exposed to a magnetic field undergo a huge, and potentially permanent, increase in their electrical conductivity." He continued: "Magnetic fields can have a minor effect on the electrical conductivity of many materials. With the ones that we describe as having colossal magnetoresistance, the effect is quite dramatic. It's almost like turning a material that used to be an electrical insulator into a conductor." Researchers have looked to magnetoresistive devices to "more effectively retrieve data from magnet storage devices, such as audio tape or computer disks."
Senator McCain, in a statement published in the Congressional Record for June 28th, said "
This appears to be in direct contradiction to the Congressional leaders' letter to the FCC, reported on in last weeks RF Current (below). During the week I heard rumors that channels as low as 52 were being discussed for auction, I found no confirmation of that from on-line legislative and governmental resources.Mr. Hundt informed me that FCC engineers foresee no problems with this auction simultaneously occurring while a transition to digital TV occurs.
Based on that evidence, I can see no reason whatsoever for an auction of channels 60 to 69 not to occur. Any effort to thwart an auction of these channels is being done in direct contradiction of the needs of the best interests of the American people."
Several announcements from Intercast today indicate the industry organization's effort to standardize data transmitted over TV signals (broadcast and cable) is succeeding. On the hardware side, one press release announced that CompUSA will offer Intercast hardware bundled with Compaq Presario PC's starting in mid-July. NBC Interactive Media and NBC Sports announced they would use more than 70 hours of Olympic Games programming to "showcase the new IntercastTM medium." The Intercast Press Release quotes Tom Rogers, Executive Vice President, NBC, and President, NBC Cable and Business Development saying "This is the true introduction of interactive television into the home. The convergence of the PC, TV and the Internet is here, now." NBC's Intercast programming will consist of exclusive, Intercast technology related material as well as well as material from NBC's Olympic Web Site.
NBC's Intercast activities will not be limited to the Olympic Games. Another announcementoutlined NBC's plans to add Intercast pages to NBC's "Homicide: Life on the Street" and other news and sports programs. Intel will be a sponsor on these programs.
Last week leaders of both the U.S. House and Senate sent a letter to FCC Chairman Reed Hundt asking the Commission to "move forward as expeditiously as possible on its current plan to award a second license to television broadcasters fo the transition to advanced television services...". It also urged the Commission to base surrender of the analog license on public acceptance of digital technology, based on adequate penetration of digital receivers. The letter recommended:
"...that the Commission complete all actions necessary to prescribe rules to permit the deployment of over-the-air digital broadcasting no later than April 1, 1997. These rules should include: (1) rules establishing a broadcasting standard for terrestrial, over-the-air digital broadcasting; (2) rules governing the assignment and regulation of terrestrial, over-the-air digital broadcasting including rules implementing Section 336 of the Communications Act; and (3) a table of allotment for terrestrial, over-the-air digital broadcasting."
In direct contradiction of some rumors currently circulating among broadcasters, the letter left no doubt that it did not want the Commission to reallocate TV broadcast spectrum. It said:
"We would strongly discourage the commission from adopting any spectrum reallocation plans, including the reallocation of spectrum assigned to the upper UHF band, which would impede not only the transition to digital television for TV channels 2 through 69 but would impact the recovery and repacking of the so-called "analog" spectrum. We should note the Commission's own recognition of the technical and economic uncertainties surrounding such proposals during the testimony before Congress(See, Testimony of Robert M. Pepper, Chief, Office of Plans and Policy, FCC, before the House Subcommittee on Telecommunications and Finance, March 21, 1996)."
The full text of the letter is available from the HDTV Newsletter.
Lucent Techologies, in a Press Release issued today, said it would collaborate with Mitsubishi Electric Corp. on the development of "a set of semiconductor chips that together will perform all of the functions needed for next-generation high-definition television (HDTV) sets for the U.S. market." The chip set will be in compliance with the ATSC (Grand Alliance)Digital TV standard recommended by the FCC in its Fifth Further Notice of Proposed Rule Making in MM Docket No. 87-268. The chip set's functions include reception, processing and display of the HDTV signal. The Release said that the first samples of the chip set will be available from both companies in early 1998.
Today, in Public Notice pnwl6058 the FCC announced that, effective immediately, the complete Land Mobile license file, including Auxiliary Broadcast Licenses (remote and low power) is available from the FCC's FTP site. The Notice said that "Daily updates will be posted on a five workday cycle (i.e. Monday's data will be overlaid by the following Monday, Tuesday's data will be overlaid by the following Tuesday, etc.)." The FTP address listed in the Notice will not work, as the capitalization of the directory headings is incorrect. The address ftp.fcc.gov/pub/Bureaus/Wireless/LM_license/ should work.
Yesterday the FCC released a News Report (DC 96-57) saying it had amended its "rules to allow broadcast television licensees to transmit ancillary digital data within the video portion of the standard NTSC television signal." The four approved transmission methods can be used by all broadcast licenses, including LPTV, without prior FCC approval and without compromising "the essential integrity of the delivered NTSC television picture or causing and our harmful effects on the television viewing public."
The methods approved are the "overscan" methods of transmission proposed by Tes! Entertainment Corporation and A.C. Nielsen Company and the "sub-video" methods proposed by Digideck, Inc. and WavePhore, Inc. En Technology Corporation's "signal substitution" method was not approved. The FCC said En would have to provide more information or "request an experiment authorization in order for the FCC to consider the system."
More details are available in the FCC's News Report (DC 96-57) and in a press release from WavePhore. WavePhore also has a page on Multimedia Datacasting.
UPDATE (June 28) - Full text of the Report and Order on MM Docket 95-42 is now available on-line.
The FCC's new procedure for registering towers becomes effective July 1st, 1996 (Monday). In a Public Notice released last week, the Commission encouraged owners to use the Internet and electronic filing technologies for entering their antenna structure registration information. Details on the registration process can be found in Fact Sheet PR 5000 #15. Refer to the Public Notice for specifics on electronic filing. Information must be submitted, in the flat file format defined, as an e-mail file attachment.
Andrew Corporation has posted a press release describing the selection of its antenna and transmission line products for Capitol Broadcasting Company's WRAL-HD experimental HDTV station on the Andrew Web Site.
Return to The RF Page @ www.transmitter.com
Last modified August 5, 1996 by Doug Lung dlung@transmitter.com
Copyright © 1996 H. Douglas Lung