RF CURRENT

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 September 1997. 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. If you find a changed link, I'd appreciate it if you'd let me know by dropping me a note indicating the new location at dlung@transmitter.com.

September 29 - Issue 88 Final Edition

SATELLITE - PANAMSAT Asks for V-Band Frequencies for Global Network (Sept. 29)
PanAmSat Corporation said today that it had requested authorization from the FCC to lauch a 12-satelite global network to "provide digital transmissions services in the V-band frequencies." V-band includes frequencies between 40 and 50 GHz. PanAmSat said "Key components of the system will include inter-satellite links, on-board processing and high-powered spot beams. Through the use use of these technologies the V-Stream system is expected to be capable of efficiently providing a full range of digital satellite services on a global basis." PanAmSat has request authorization for 11 orbital slots, ranging from 99 degrees West longitude (the current location of Hughes Galaxy IV) to 124.5 degrees East longitude.

PanAmSat is not the only company interested in this band. See the July 28th RF Current for information on other activity here. More information is available in the PanAmSat Press Release.

SATELLITE - INTELSAT 803 Successfully Launched (Sept. 23)
INTELSAT announced today that it had successfully launched INTELSAT 803 from Kourou, French Guiana aboard an Arianespace Ariane 42L launch vehicle. As part of the satellite redeployment described in the September 15th RF Current, the satellite will be temporarily deployed at 332.5º East Longitude.

The INTELSAT 803 orbital maneuvers are scheduled to be completed September 29, its solar arrays are scheduled to be deployed October 1, along with the C and Ku band reflectors. The reflector deployment should be completed on October 2nd. The satellite is scheduled to begin service in October at 332.5º East Longitude.

More information is available in the INTELSAT Press Release. In other INTELSAT news, the FCC granted COMSAT's application for authority to participate in the launch and construction of up to four INTELSAT VIII satellites and provides authorized services via these facilities. See the FCC's International Bureau Order DA97-2038. This order also covers the redeployment of satellites reported earlier. Other recent FCC actions affecting INTELSAT can be found in International Bureau Orders DA97-2037 - Application for authority to participate in the launch of INTELSAT VIII (F-4) and DA97-2036 - Application for authority to participate in the launch of INTELSAT VIII (F-3).

DTV - LPTV Stations File for Digital Transmission (Sept. 23)
The Mass Media Bureau's September 23 listing of applications accepted for processing showed two applications filed for construction permits to operate an experimental broadcasting station using the facilities of an existing Low Power Television station in a digital format. The stations involved were K49DF, licensed to Jeff Jacobsen in Phoenix, Arizona and KACY-LP on channel 24, licensed to Robert W. Fisher in Houston, Texas. No other details were available nor did the notice say whether these stations would use the 8-VSB modulation format adopted for high power DTV or one of the QAM formats favored by some digital MMDS operators.

FCC Proposes TV Set V-Chip Requirements for Program Blocking - CEMA Objects (Sept. 26)
Yesterday the FCC proposed technical requirements to enable blocking of video programming based on program ratings, using technology commonly called the "V-chip". The Commission's proposal would amend Parts 73, 74 and 76 of the FCC rules to "ensure any ratings information that is provided with video programming is transmitted to the television receiver intact, without disruption by any broadcast, cable television, satellite or other video programming distribution service." Similar requirements would apply to Direct Broadcast Satellite (DBS) services and multipoint distribution services (MMDS).

Under the proposed rule, all television manufacturers would " be required to provide blocking technology on at least half of their product models with a picture screen 33cm (13 inches) or greater in size by July 1, 1998. The remainder of the models would be required to contain blocking technology by July 1, 1999."

The Consumer Electronics Manufacturers Association questioned whether its member could have the technology in sets by July 1998. CEMA president Gary Shapiro stated that "the earliest that manufacturers could produce some models with this blocking technology is the middle of 1999." He added that while "Manufacturers will move as fast as humanly possible to meet the statutory requirements..." He added "Manufacturers tell us they can not meet the deadline. The Commission needs to be more flexible in its expections..." The legal mandate and the "new ratings system now before the FCC requires technical changes and final agreement on a standard. After final agreement, manufacturers can finally design, build and sell sets with V-chip."

More information is available in the FCC News Release NRET7013, the FCC Notice of Proposed Rulemaking FCC97340 and the CEMA Press Release.

TECHNOLOGY - RADAR Flashlight Sees Through Walls (Sept. 24)
The Georgia Tech Research Institute has developed a RADAR flashlight that uses a low level FM microwave RADAR and a specialized signal processor to discern respiration up to three meters away through walls and doors with no physical connection between the subject and the RADAR. The research that led to the device "began in the mid-1980's with the patenting of a frequency modulated radar for remotely checking vital signs of battlefield wounded before risking medics' lives."

Potential applications included locating people in a room (and determining their state based on respiration) during a hostage situation and locating survivors in the rubble from earthquakes or other disasters. More information on this technology is available in a Georgia Tech News Release.

OTHER Items of Interest


September 22 - Issue 87 Final Edition

FCC Releases Spectrum Auction Schedule for 1998 - TV Channels Pending (Sept. 19)
Thursday the FCC's Wireless Telecommunications Bureau (WTB) released a Public Notice outlining planned spectrum auctions for 1998. During the first quarter of 1998, the WTB plans to auction spectrum in the 220 MHz. and 929-931 MHz. bands.

The Public Notice also listed other services that could be auctioned in 1998, some subject to the outcome of pending rulemakings or other matters. The spectrum included in this list includes 200 channels in the 800 MHz. band, lower band paging frequencies (35-36, 43-44, 152-159 and 454-460 MHz.), 4660-4685 MHz, for General Wireless Communications Services, various services in the 901-960 MHz. range, public coast stations in HF and VHF bands, 38.6-40.0 GHz., and pending analog broadcasting channels for commercial radio and television stations.

More information is available in the FCC Public Notice DA972024.

FCC Experimental License Grants for August (Sept. 19)
The FCC's Office of Engineering and Technology, Experimental Licensing Branch, released its listing of Experimental Actions for August this week. Items of interest include a license granted to TASC, Inc. to use 925-928 and 935-940 MHz. and other frequencies in the 1850-1990 MHz. range for test and development of equipment in the Reston, VA area. NEC America received authorization to use frequencies in the 28-29 GHz. region to test and develop LMDS services and equipment throughout the continental United States.

For specific frequencies and a listing of other experimental grants see the Public Notice (PNET7020).

DTV - Broadcasters Outline HDTV Plans at Senate Commerce Committee Hearing (Sept. 18)
Senate Commerce Committee Chairman John McCain opened Wednesday's hearing to "examine the extent and significance of possible changes in the kinds of programming television broadcasters may be preparing to offer television viewers as they implement digital broadcasting service." The hearing was called after some broadcasters made statements that they, as McCain stated "may intend to use their digital spectrum primarily to broadcast multiple channels of standard-definition programming, perhaps on a subscription basis, rather than for free over-the-air high definitiion television programming." He quoted Westinghouse chairman Michael Jordon's comments that "This whole digital transition has been left to the engineers until just about six months ago. All of a sudden we got this thing approved and nobody has a clue what they are going to do." He found this statement and others "troubling on several levels". He stated his key concern was that after being given "tens of billions of dollars of public property in digital spectrum", if broadcasters really didn't know what to do with it "consumers may lose twice: having first lost the auction value of the spectrum, the public now has no real certainty of what they're likely to get in return or when they're likely to get it." Chairman McCain stated "And I will not accept that." (see Chairman McCain's Opening Statement)

FCC Chairman Reed Hundt called for allowing flexibility in broadcasters choice of format for DTV, which he preferred to the term HDTV, commenting that "DTV encompasses all the possibilities that digital technology can bring..." Hundt had strong words for those advocating a government mandated format. He asked "what conceivable business does the government have in making that choice? Is it the business of government to micromanage picture quality? The government doesn't adjust the color or my reception now, and certainly doesn't need to do so in the future. The market will figure this out; consumers will dictate whether broadcasters should broadcast one or two HDTV programs, or six or eight standard definition programs." Hundt also urged the lawmakers not to water down the return date for the analog spectrum. See Hundt's Statement for more information.

Robert Dechard, President and CEO of A.H. Belo Corporation, saw no business value in a multichannel format. He said "the major focus of our transition to digital has been the high end of digital television, or HDTV... we are committed to it; and see it as a competitive necessity." He questioned where broadcasters would find the programming to fill additional channels. However, he emphasized "Programming flexibility is clearly needed to accommodate future technological advances." Preston Padden, President of the ABC Television Network, attempted to correct misconceptions he said may have arisen from his earlier comments. He siad "ABC still remaisn committed to broadcast some HDTV programming. We remain committed to giving HDTV a fair market test." He also said ABC had no plans to use the digital spectrum to transmit subscription programming. Padden said that while multichannel programming may warrant exploration, "we have not yet come up with a plan to make it work."

David Smith, President of Sinclair Broadcast Group, Inc., said "unequivocally....Sinclair is committed to free over-the-air television." He said "Sinclair intends to explore a high definition television (HDTV) business model which may include HDTV and multichannel broadcasting." He outlined some of the possibilities for multichannel programming such as regionalized local news or a combination of HDTV for covering football plays with replays on different SDTV channels. He commented that for DTV to succeed, broadcasters must be able to provide what the consumer wants. With large screen HDTV sets initially selling for $8,000 to $10,000 each, he said "Television is not intended for only the wealthy; it is the common thread linking Americans and should be priced within the budgets of all Americans."

All three broadcast representatives reminded the Committee of the expense and effort they and other broadcasters have accepted to bring DTV to the consumer. The huge expense of the two step process to construct transmission facilities on the World Trade Center in New York was mentioned, as was the difficulty in obtaining approval to construct the towers many stations will need to broadcast DTV. They asked for help in overcoming local zoning disputes concerning the construction of new towers and asked for the Committee's support. David Smith noted the 20 to 1 power disparities between DTV stations in some markets and said that was a major risk for UHF broadcasters, who in most cases received the lower power levels.

Full text of the statements of Robert Decherd (A.H. Belo), Preston Padden (ABC) and David Smith (Sinclair) is available from the Senate Commerce Committee's Hearings web page.

DTV - TV Set Manufacturers Promise DTV's in late 1998 (Sept. 19)
The same week as the Senate Commerce Committee hearings (see above), three major broadcasters of consumer electronics offered their support for Digital TV. Mitsubishi Consumer Electronics America, Inc. said that starting in the fall of 1998, it will offer in the U.S. Digital HDTV receivers that fully support the ATSC digital TV/HDTV specifications, including wide-screen HDTV.

Sony Electronics issued a statement saying "Sony Electronics is working toward the fall 1998 introduction of a lineup of consumer digital television receivers in the United States that will receive Advanced Television Systems Committee digital signal formats, including wide-screen HDTV." Sony also said will offer "oappropriate broadcast-use equipment" to enable broadcasters and cable operators to provide digital HDTV.

Matsushita Electric Corporation of America said it and its Panasonic sales subsidiaries are "developing a line of HDTV and DTV products to meet anticipated consumer demand in the second half of 1998." The Panasonic news release also mentioned Panasonic and Matsushita's role in providing digital and HDTV video equipment to major broadcast networks.

OTHER Items of Interest


September 15 - Issue 86 Final Edition

SATELLITE - INTELSAT Shuffles Satellites to Cover 605 Anomaly (Sept. 12)
Friday INTELSAT outlined its plans to modify its satellite deployment plan to "accomodate an anomaly experienced yesterday on the INTELSAT 605 satellite located at 335.5 degrees East."

A Press Release said "The 605 spacecraft experienced a deficiency of telemetry which may eventually affect INTELSAT's ability to monitor the satellite in a normal operational manner. There is no effect on the traffic carried on the satellite and none is anticipated."

Under the new deployment plan, an INTELSAT VIII will be deployed to 332.5º E to release INTELSAT 601, which will be relocated to 325.5º E to release INTELSAT 603. INTELSAT 603 will move to 335.5º E to replace INTELSAT 605, which will "be relocated to perform a new operational role." INTELSAT emphasized that this deployment plan was developed as a precautionary measure.

ENGINEERING - Johns Hopkins University Builds "Virtual Lab" on the Web (Sept. 12)
Michael Karweit, a professor at Johns Hopkins University in Baltimore, Maryland has built a "virtual laboratory" where students and the public can work on engineering tasks that include drilling for a hidden supply of oil, programming a robotic arm and designing digital logic circuits. Karweit's work won him a "best paper" award at a recent meeting of the Association for the Advancement of Computing in Education.

More details on the "Virtual Laboratory" are available in the News Release from Johns Hopkins University. You can test your skills in the laboratory at http://www.jhu.edu/~virtlab/.

September 8 - Issue 85 Final Edition

TECHNOLOGY - Space Tether: Use Magnetism to Move Satellites (Sept. 8)
The March 1996 RF Current covered the space tether experiments on the Space Shuttle. Now, over a year later, NASA's Marshall Space Flight Center has released an interesting article on using the currents generated in the tether to control a spacecraft's passage around the earth. One model being developed is a device that would use the Earth's magnetic fields to cause rocket stage to re-enter the atmosphere in days instead of months. More exciting is the suggestion that the tether's coupling to the Earth's magnetic field could be used to maintain the orbit of a satellite or space station by feeding voltage into it. In the case of the International Space Station, NASA said it could trim $2 billion a year off the cost of keeping it in orbit.

Most readers of this page will be able to visualize how the tether could work with the Earth's magnetic fields to be either a generator of electricity or a motor to raise or lower a satellite's orbit. This is interesting technology. For more details and illustrations see Up, Up and Away (bit by bit) on the Marshall Space Flight Center's web site.

CONSUMER - Curtis Mathes to Bring DLP to Big Screen TV (Sept. 5)
Curtis Mathes announced it was joining with Davis A/S to make Texas Instrument's innovative Digital Light Processor (DLP) technology to consumers. Curtis Mathes will market Davis' Powerscreen system to consumers through high-end installer / distributors. TI's DLP technology uses micro-mirrors to project an image on a screen. The Powerscreen system will have a resolution of 800x600 pixels, comparable to computer SVGA.

No prices were available from the Curtis Mathes or Davis A/S web sites. DLP technology has the potential, if it becomes a mass market item, to bring the cost of HDTV quality big screen displays down to an affordable level. Currently DLP computer presentation projectors sell in the same price range as LCD based projectors. Sony showed professional DLP projectors at the 1997 National Association of Broadcasters Convention, so it is reasonable to expect Sony will make the technology available in consumer products as DLP prices drop.

See the Curtis Mathes Press Release for more information on this marketing arrangement. Davis has Powerscreen brochure and technical specifications available on its web site. Texas Instruments' DLP Page has links to wealth of information on the technology behind and the application of DLP.

FCC Announces Public Access to Licensing Databases (Sept. 4)
The FCC is allowing web based public access to its licensing databases on a trial basis. The databases available are those regulated by the Wireless Telecommunications Bureau and include Land Mobile and Amateur Radio licenses, among others. The beta test is located at http://gullfoss.fcc.gov:8080/beta.htm. Forms will guide you through the search. Once the public testing period is over, the FCC Public Notice said the databases will be available on the FCC's wide area network for a charge of $2,30 per minute. It also noted the first two minutes of access will be free.

Contact betacomm@fcc.gov to enroll as an official beta tester and receive E-mail notification when new programs are available for testing. I hope the FCC does not go the route it took on with the tower registration programs, which require the set up of a non-Internet TCP/IP connection for access. I was unable to get the FCC software to install on my system due to conflicts with the built in TCP/IP stack included in Windows 95.

DTV - First DTV Construction Permit Goes to KHVO Hilo Hawaii (Sept. 3)
The FCC's Mass Media Bureau, in a News Release issued today, said it had issued the first DTV construction permit for KITV Argyle Television, Inc.'s KHVO DTV Channel 18 in Hilo, Hawaii. This CP was granted under the FCC's "certification checklist", which expedites applications when the applicant is able to check "yes" to five questions. The questions determine whether the facilities do not exceed those in the FCC's DTV Table of Allotments and the DTV antenna site is within 5 km. of the site used in creating the Table. Applicants must also state the proposed facility would comply with the Commission's RF radiation and environmental requirements. A registered or FAA approved tower is also required.

KHVO's antenna is located on a short tower on the roof of the Naniloa hotel on Hilo's Banyan Drive, 44 meters above sea level. The antenna will be an RPS Model PHP2B, generating an average DTV ERP of 5.4 kW. Itelco will supply the transmitter for KHVO, as well the the other Argyle Television stations in Hawaii. See the Itelco Press Release for information on this purchase. (note - location confirmed Sept. 10)

FCC database watchers will be interested to know this DTV CP is listed in the September 4, 1997 FCC Engineering Database, available from the FCC's Mass Media Bureau.

OTHER Items of Interest


September 1 - Issue 84 Final Edition

DTV - Philips Forms Group to Use TriMediaTM Processors for DTV from HD to PC (Aug. 29)
Philips Semiconductors, in a Press Release issued Friday, said it was forming a new project group based in Sunnyvale, CA to support its DTV initiative. Philips' efforts are based on its TriMediaTM media processor. Arthur van der Poel, Chairman and CEO of Philips Semiconductors, said "A major advantage of the TriMedia solution is that is is future-proof. As new services evolve in the DTV environment, the appropriate software is simply downloaded into the TriMedia-enabled Digital TV."

Some of the capabilities claimed for the TriMediaTM processor include the ability to support all 18 ATSC DTV formats along with the existing NTSC format, other data streams such as different cameras views or web page delivery and a reverse communications link for interactive services such as Internet access or games.

Philips' TriMediaTM processor reflects the efforts consumer electronics manufacturers are making to get around one of the major problems with DTV's early roll-out -- a lack of detailed operating standards. Arthur van der Poel commented that "Although the DTV standard makes provision to broadcast data for additional consumer services, the standards for these services are not defined. Philips Semiconductors, in co-operation with Philips Sound and Vision, plans to work with industry leaders to begin to establish open standards for all the new services made possible by the DTV environment."

DTV - CableLabs Begins Second Round of Meetings on DTV Request for Info (Aug. 29)
Earlier this year CableLabs requested information from companies interested in developing digital devices for cable systems. Friday CableLabs web site announced CableLabs formulated a set of follow-up questions and "has also begun setting up a round of confidential meetings between vendors and senior technical and business development executives from our member companies."

An Adobe Acrobat document on the CableLabs web site outlines the questions and provides details for companies wishing to participate in this effort.

SATELLITE - PanAmSat's PAS-5 Successfully Launched (Aug. 28)
PanAmSat Corporation announced its PAS-5 Atlantic Ocean Region satellite was successfully launched on a Proton rocket from the Baikonur Cosmodrome in Kazakhstan. The satellite will be used primarily for transmission to Latin America. The satellite is a Hughes HS-601 HP with a steerable spot beam for "customized, moveable coverage." It is also the first commercial satellite to employ a xenon ion propulsion system to prolong the satellite's service life.

PAS-5 is expected to begin commercial service in October 1997 at an orbital location of 58 degrees West Longitude. Technical details, including coverage maps, are available on the PanAmSat web site.

DTV - ATSC Conducts First Over the Air HDTV broadcast in China (Aug. 27)
The Advanced Television Systems Committee (ATSC) broadcast a digital HDTV signal from the central TV tower in Beijing to the Great Wall in Ba Da Ling, 55 km. away. This became the first digital HDTV broadcast in China, according to the ATSC. The demonstration was conducted in conjunction with the 1997 International Symposium on Broadcasting Technology (ISBT). ATSC said additional demonstrations would be held throughout the symposium, which ends August 31.

Robert Graves, ATSC Chairman, after outlining the advantages of the ATSC DTV standard, added that " ...implementing common or similar digital television standards in many countries will benefit those countries by providing wider availability of broadcast and consumer equipment at lower prices. We look forward to working with manufacturers and broadcasters in implementing this standard throughout the world."

For more information see the ATSC Press Release.

TECHNOLOGY - TINY SPHERES ABSORB NOISE (Aug 26)
Last week the Georgia Institute of Technology issued a News Release describing a new acoustic liner material using tiny spheres to absorb noise and withstand high temperatures. The spheres were orginally developed at Georgia Tech almost 10 years ago for use as a high temperature insulation. The new studies show they also "offer competitive noise-absorption properties."

The little spheres, 1 to 5 millimeters in diameter, have an advantage over other acoustic liner materials, which usually come in preshaped forms. The spheres can be poured into existing structures, such as the walls of homes, hotels, concert halls or even the framework of aircraft and automobiles. Encased in a quilt like fabric, they could be used as portable sound curtains in noisy factories other places where permanent structures aren't needed.

While reduction of noise from blowers and other mechanical equipment at TV transmitter sites wasn't mentioned in the release, it is certainly an area that could benefit from noise reduction technology. More details on this interesting technology and additional links are available in the Georgia Tech Research News Release.

FCC Issues Opinion, Order, NPRM on RF Exposure Limits and Preemption of Local Regs (Aug. 26)
As reported in last week's RF Current, the FCC's Office of Engineering and Technology released its long awaited Bulletin 65 on "Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields." On Tuesday it posted the text of its Second Memorandum Opinion and Order and Notice of Proposed Rulemaking in Wireless Docket 97-192, Engineering Technology Docket 93-62 and Cellular Telecommunications Industry Association Petition for Rulemaking RM-8577, all related to the evaluation of and regulation of the environmental effects of radiofrqeuency radiation.

Highlights include an increase in the threshold above which licensees at multiple transmitter sites must share responsibility. Under the old rules, the limit was one percent. Under this Order, the limit is increased to five percent. This should allow those stations currently meeting the exemption for a controlled environment to also meet, in most cases, the stricter limits for public or uncontrolled exposure. The blanket 50 watt power level threshold for amateur radio stations was revised and is now scaled with frequency, starting at 500 watts on the 160, 80 and 40 meter bands and decreasing to 50 watts on all VHF bands. Finally, the FCC recognized that more time was needed to bring existing sites and transmitters into compliance with the new guidelines and extended the deadline for existing stations to September 1, 2000.

Several other issues are addressed in this Order. Please see the full text FCC97303 for more information. Comments are due October 9, 1997 with reply comments due October 24, 1997.

OTHER Items of Interest


Other Issues Available:

1998

1997

1995 and 1996

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Last modified September 29, 1997 by Doug Lung dlung@transmitter.com
Copyright © 1997 H. Douglas Lung