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 December 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.

NOTICE: RF Current was not published December 1st. Items up to the U.S. Thanksgiving Holiday appeared in the November 26th Extended Edition. Items after that appear in the December 8th edition.

NOTICE: RF Current was not published on December 29th due to the Christmas and New Years holidays. The December 22 edition was kept open through December 24th. The January 5 edition will contain stories from December 25 through January 5. Enjoy the Holiday season with your family and friends. Don't forget the real reason this time of year is special. Thanks again for your comments and support. Please accept my wishes for a happy and enlightening 1998!

December 24 - Issue 99 Extended Edition

SATELLITE - Hughes Communications Outlines SPACEWAYTM System Plans(Dec. 23)
Hughes Communications announced it had filed two applications with the FCC today to increase system capacity and add higher data rate transport services to its SPACEWAYTM global broadband communiations system. A Hughes Release said "The SPACEWAY EXPTM filing outlines an eight-satellite system operating at geostationary Earth orbit (GEO), providing high data rate transport services. The SPACEWAY NGSOTM filing describes a 20-satellite system operating in nongeostationary Earth orbit (NGSO). These additions will increase overall SPACEWAY capacity, especially in high-demand areas. Both systems will operate in the Ka-band frequency range (17.7 GHz to 30.0 GHz)."

The proposed system will cover four regions: North America, Asia Pacific, Latin America and Europe-Africa-Middle East. Hughes said the system will provide "businesses and consumers with fast access to terrestrial networks, such as the Internet..." The system will work with antennas as small as 26 inches (66 cm) in diameter and provide data rates up to 6 Mbps.

SPACEWAY EXP will use geostationary satellites and focus on high data rate markets. Hughes has requested locations at 117, 69, and 26.2 West longitude and 99 East longitude. SPACEWAY NGSO will "consist of four planes with five satellites in each plane, inclined at 55 degrees with respect to the equator and in circular orbits at an altitude of 10,352 km. Hughes said the satellites with incorporate multiple-beam antennas, digital processors for switching traffic among beams, and intersatellite links to interconnect the satellites.

More information is available in the Hughes Press Release.

DTV - Samsung Tests HDTV Receiver Compatibility with ATTC and CBS (Dec. 22)
In a Press Release issued today, Samsung electronics said it had successfully competed HDTV receiver compatibility tests at the Advanced Television Test Center (ATTC) in Washington DC and at CBS Engineering laboratories in New York. Sumsung's Release claimed its 1920x1080 HDTV format will be the highest resolution at the Consumer Electronics Show, starting January 8 in Las Vegas, NV. CBS affiliate KLAS-TV will provide off-air signals for Samsung's demonstration in Room N107 of the Las Vegas Convention Center from January 8 to 11.

SATELLITE - INTELSAT 804 Launched (Dec. 21)
INTELSAT announced it has successfully launched INTELSAT 804 using an Ariane 42L launch vehicle. The satellite has 38 C-band transponders and 6 Ku-Band transponders. It will be positioned at 64 degrees East and provide service to markets in Europe, Asia and Africa. INTELSAT 804 is expected to be available for commercial service beginning in February 1998, after orbital maneuvers and in-orbit testing is completed. More details are available in the INTELSAT Press Release.

CHIPS - Panasonic Claims First Single-Chip DTV Decoder (Dec. 18)
With the first DTV sets due in the stores in less than a year, Panasonic joined the growing number of companies offering semiconductor solutions for consumer DTV sets. Panasonic said "The chip--technically termed a "Digital Television MPEG2 Main Profile at High Level Video Decoder" -- functions in both a 'full- spec' mode and a 'down-conversion' mode. In the full-spec mode, it decodes the compressed video signal from the broadcast and outputs the original format, that is, either HDTV (1080-lines interlaced or 720-lines progressive) or SDTV (480-lines interlaced or 480-lines progressive). The 'down-conversion' mode converts all compressed video signals to 480-interlaced and 480-progressive formats. This is accomplished by a memory-efficient MPEG down-conversion algorithm developed by PAVCAL [Panasonic AVC American Laboratories, Inc.] ."

The chip will decode any of the 18 ATSC formats and was designed for use in standard and high definition digital TV sets, digital set-top boxes, computers and other digital products. It will be in products demonstrated at the Consumer Electronics Show in Las Vegas January 8-11. More information is available in the Panasonic Press Release.

FCC Requests Comments on Fee Alternatives for Ancillary or Supplementary DTV Services (Dec. 18)
The FCC is requesting comments on "various fee alternatives for broadcasters' use of excess digital capacity to offer certain services that would be 'ancillary or supplementary' to their over-the-air digital broadcast (DTV) signals." No fees would be accessed for advertiser supported services

A News Release (nrmm7021) summarizes the request. More details are available in the complete text of the Notice of Proposed Rule Making. (also available as a WordPerfect document.)

FCC Chairman Kennard's Statement said the proceeding would "provide guidance to broadcasters as they continue to build-out their DTV stations." Commissioner Susan Ness, in her statement, said "Congress has made it abundantly clear that it fully expects broadcasters to focus their digital capacity on providing their local communities with a wealth of free broadcast programming, including programming transmitted in high definition. While the opportunity to provide many new and exciting services is available through the flexibility of the digital standard, I do not anticipate broadcasters will abandon their birthright of top quality free video broadcasting."

FCC Experimental Actions In November (Dec. 17)
The FCC has released its monthly list of experimental actions. Most are for licenses to use IMMARSAT terminals, however one may be of interest to readers - WA2XOT, Motorola, Inc. to use 2450-2500 and 2162- 2180 MHz. for test and development of equipment for wireless cable data networks in Schaumburg, Illinois. See the Public Notice (pnet7028) for the entire listing.

CHIPS - NDS, Motorola and Alps Deliver DTTV Chip Set Solution (Dec. 17)
While most of the focus on terrestrial digital TV has been with the U.S. ATSC DTV system, the European community is also beginning a DTV build-out. The European system is based on the MPEG-2, DVB-compliant data and a COFDM transmission system. Motorola and Alps said their "front-end solution" is "achieved with three chips which provide Coded Orthogonal Frequency Division Multiplex (COFDM) demodulation, 2K-mode Fast Fourier Transform (2K-FFT) processing, and forward Error Correction (FEC)." A Motorola Press Release said: "The new DTTV front-end solution takes signals from existing roof top aerials and demodulates them using the DVB-T specification, and outputs an MPEG-2 stream for use in digital TV sets or digital set-top boxes. The front-end has been designed to receive 2K carrier DVB compliant signals, the profile for DTTV broadcasting in the U.K. as specified by the d-MUX organization."

Samples of the three chip set are available now. Production release is scheduled for first quarter 1998.

SATELLITE - INTELSAT and Columbia Communications Resolve Orbital Slot Issue (Dec. 16)
Both INTELSAT and Columbia Communications had claimed the 319/319.5 degree East orbital slot position. In a Press Release issued today, INTELSAT said they had reached an agreement on the slot. It said "Under the terms of the agreement, Columbia will cease operation of the TDRS-4 spacecraft at the 319E/41W location by 15 May 1998. In its place, Columbia will take title to the INTELSAT 515 spacecraft, to be renamed Columbia 515, and begin operating that satellite by 1 April 1998 at 322.5E/37.5W. Columbia will lease back to INTELSAT at no charge a number of transponders on the Columbia 515 satellite."

More information on Columbia Communications is available at http://www.tdrss.com.

DTV - ATSC Group to Tackle Data Broadcasting Over ATSC Broadcast Systems (Dec. 16)
A new ad hoc group on Data Broadcasting Implementation will meet January 8, 1998 in Washington D.C. "to create a list of requirements and recommended practices that will allow a preferred implementation/recommended practice to be created for data sources to be connected to ATSC broadcast systems in a known and implementable way."

The meeting will focus on these issues:

For details on how to participate or to obtain more information see http://www.atsc.org/Data_Implementation.html.

OTHER Items of Interest

December 15 - Issue 98 Edition

FCC To Consider Fees for Ancillary or Supplementary Use of DTV Spectrum (Dec. 15)
The Agenda for the FCC Open Meeting on December 18th lists an item where "The Commission will consider action concerning implementing the transition to digital television (DTV) for existing television broadcasters in accordance with the provisions of the Telecommunications Act of 1996 regarding fees for ancillary or supplementary use of DTV spectrum."

Also being considered are "substantive amendment and modifications to the Commisson's general competitive bidding rules for all auctionable services that are intended to simplify the Commission's regulations, eliminate unncessary rules wherever possible and increase the efficiency of the competitive bidding process."

The audio portion of the meeting will be broadcast live on the Internet. See the FCC's Internet audio broadcast page at http://www.fcc.gov/realaudio/. Following the open meeting the Commission will hear a presentation on the status of competition in the multichannel video industry. Details on this are available in the Public Notice (pnmc7025)

Satellite - INTELSAT Finds Spot for Recovered 605 Satellite, Plans New Launches (Dec. 11)
As reported in the September and October issues of RF Current, INTELSAT engineers developed a method for working around the telemetry anomaly detected in the 605 satellite in September. The INTELSAT Board of Governors was satisfied with the performance of this fix and, at their December 6-11 meeting, decided to deploy 605 at 332.5 degrees east. An INTELSAT Press Release noted that "The new decision to assign this spacecraft to the 332.5E location...represents the conclusion of extensive analyses and tests which began on 11 September, and INTELSAT's succsss in devising a ground-based solution to compensate for the loss of the telemetry information.

At the same meeting mentioned above, the INTELSAT Board of Governors also authorized procurement of two additional INTELSAT spacecraft, and procurement of three launches on Ariane 5 launch vehicles for INTELSAT 902,. 903 and 904. The INTELSAT IX series satellites are built by Space Systems / Loral. More information is available in a Press Release.

TECHNOLOGY - ParkerVision Claims First Universal Direct Conversion Receiver IC's (Dec. 10)
If you've experimented building radio receivers, you've probably build one of the simple "direct conversion" receivers for reception of shortwave signals. I used a direct conversion receiver as the basis for my frequency calibrator described in my March and May 1994 RF Columns in TV Technology (also see the drawing). It appears ParkerVision has taken this simple receiver approach and refined it into a commercial product.

According to the company's news release, "The 'Eddie' chip receives and processes any frequency from 1 MHz. to 1 GHz., consumes less than 10 mA of power, passes signal bandwidths up to 3 MHz, provides excellent signal to noise allowing for high gain/high sensitivity, and costs a fraction of the current RF electronics that Eddie replaces."

ParkerVision CEO Jeffrey Parker said "We are certain that there are also many new wireless architectures that our technology now makes possible. For example, with our Universal Direct Conversion Receiver technology we created a very low cost FM data link that can move megabits of digital data and has over 100 times (20db) more interference rejection than a traditional FM link, yet costs much less. This kind of reliability and low cost is lacking in today's RF electronics. In addition to the benefits that can be derived from applying our technology to traditional wireless products, our goal is to help create new and unique products and systems in concert with those visionaries who have been waiting for the breakthroughs that our technology represents, and together raise the standards by which RF products are judged.

SCIENCE - Scientist Find Magnetosphere May be Filled by Energized Gas From Earth's Pole (Dec. 9)
Scientists have generally believes the Earth's magnetic field captured a lot of the solar wind and formed the giant cloud of electrified gas that surrounds our planet. Now Dr. Rick Chappel and Dr. Barbara Giles will present papers showing that this magnetosphere may actually be filled by a fountain of energized gas blowing from the north and south poles.

NASA's Marshall Space Flight Center has posted an outline of the findings on a very interested and well illustrated web page. If this subject interests you, check out Earth Weaves Its Own Invisible Cloak.

OTHER Items of Interest

December 8 - Issue 97 Final Edition

DTV - ATSC Issues RFI on Standard for Satellite Transmission of DTV Signals (Dec. 8)
The ATSC Specialist group on Satellite Transmission has issued a Request for Information "with the goal of defining the paramters of importance for a voluntary ATSC standard for satellite transmission of DTV signals." It said such a voluntary standard and recommend practicies for satellite distribution of DTV would allow manufacturers to build equipment that which will be interoperable with equipment from other manufacturers, allow TV networks to share signals feeds (at their discretion) and make it possible for satellite owners and users to "understand the operating objectives for DTV satellite transmission."

The RFI defines three types of satellite transmission: contribution - such as program source material in its original or very early form, distribution - program material nearly in its final form except for processing at local broadcast facilities, and Direct-to-home (DTH) - programs packages and processed for reception by end users.

The deadline for responding to the RFI is December 15, 1997. The complete RFI is available in HTML, see T3/S14 Request For Information. Also see http://www.atsc.org/T3S14_RFI_information.html.

FCC Seeks Comment on DTV Channel Allotment Filings (Dec. 3)
Yesterday the FCC issued a Public Notice (pnmm7238) requesting comment on filings by the Association for Maximum Service Broadcasters, Inc. (MSTV) and others requesting changes to the FCC's DTV Table of Allotments. The MSTV filing suggested making 357 changes to the table to reduce interference to both analog and DTV stations in the most congested areas of the U.S. and cure "a large number" of the case of DTV-DTV adjacent channel short spacings.

The Public Notice also asked for comment on the proposal from the Association of Local Television Stations, Inc. (ALTV) to address the disparity in authorized power between UHF DTV facilities of VHF NTSC stations and UHF DTV facilities of UHF NTSC stations. The ALTV proposal would permit DTV stations to increase power to 1000 kW, provided they used antenna beam-tilt and/or other technologies to prevent "any incremental visibile interference." This proposal does not seek changes in channel assignments.

The FCC said it would provide a single, brief 15 day period for response to these filings. Specifically, the FCC said "We request comment on whether the proposals set forth in these filings by MSTV and ALTV represent full industry agreements." "With regard to MSTV's filing, we seek comment on whether the issues raised by MSTV are more appropriately handled on an individual case-by-case basis or through a new Table." "With regard to the ALTV filing, we request comment on how such an antenna beam tilt approach would relate to other solutions for resolving the UHF power problem." Comments must be submitted on or before December 17th.

DTV - SRI Consulting Study Says Most Viewers Will Watch DTV Using Converter Boxes (Dec. 3)
SRI-Consulting said a new study it conducted found most of the the 12 million consumers worldwide who will watch terrestrial DTV in the next ten years will use a digital converter box rather than a digital TV set. The high cost of digital HDTV and digital SDTV TV sets was listed as the reason most consumers will go with converter boxes.

Paul Di Senso, senior consultant and lead researcher for the "Digital Broadcast Television" report issued by SRI Consulting, said "The high cost of digital-TV sets means that most consumers who want to watch digital terrestrial broadcasts will choose to buy or rent a converter box."

DTV - First Commercial DTV Television Stations On-Air (Dec. 2)
KITV-DT begain transmitting ATSC digital television at 3:34 PM HST, November 28th, in Honolulu, Hawaii. It was joined by satellite station KHVO-DT, Hilo, Hawaii on December 2nd at 8:59 PM. An Itelco Press Release noted these two stations are the first commercially licensed digital television stations in the United States. Itelco supplied the liquid-cooled solid state transmitters used at these stations.

KITV-DT transmits from an antenna atop the Ala Moana Hotel in Honolulu. The KHVO-DT antenna is mounted below the KHVO NTSC antenna on top the Naniloa Hotel in Hilo. (Editor's note - when I drove by the Naniloa Hotel in Hilo December 7th I noticed two RFS panel antennas mounted side by side, for a narrow beam, on the short tower supporting KHVO's main VHF antenna. Unfortunately, I didn't have a portable Sony Digital Watchman with me so I couldn't verify what the station was actually transmitting!)

Studio and transmitter facilities were designed by and constructed under the supervision of Thomas L. Mann, Garrison C. Cavell and Joseph Davis, principals in Cavell, Mertz and Perryman, Inc., Consulting Engineers, Fairfax, Virginia and Los Angeles, California. Antenna installatin was done by LDL Communications, Inc. Philips BTS provided the Grand Alliance digital encoders and interface.

DTV - Canada and South Korea Adopt ATSC Standard (Dec. 1)
ATSC said that the Department of Industry of the Canadian government formally adopted the ATSC DTV Standard on November 8th. The Korean Ministry of Information and Communication selected the ATSC standard on November 21. Robert Graves, Chairman of the ATSC, said:
"We believe these countries are the first of many throughout North and South America, Australia, and Asia that will adopt our standard." Canada and Mexico participated extensively in the U.S. process during the past ten years to help develop what was always intended to be a North American standard. Consequently, Mexico is considered certain to adopt the Standard along with all of Central America. Moreover, Brazil and Argentina are carefully evaluating the ATSC Standard, and the chances are excellent that it will be adopted throughout all of South America. In Australia, laboratory and field tests have recently been completed as part of an extensive evaluation of the ATSC Standard and the competing European standard, and here again the prospects for adoption of the ATSC Standard are excellent. In Asia, in addition to the recent Korean decision, Taiwan has made a tentative decision to adopt the ATSC Standard, and China is conducting a careful evaluation where once again the prospects for the ATSC Standard are excellent."
More details are available in the ATSC Press Release.

DTV - Intel Files for Experiment TV License (Dec. 1)
The November 28, 1997 Broadcast Applications listed in today's FCC Daily Business included an application from Intel Corporation in Santa Clara, California, requesting a construction permit for a new experimental television station on channels 6, 12, 28 and 62. The ERP listed was 18 kW (vis.) and the transmitter location was given as 2200 Mission College Blvd., Santa Clara, CA. The antenna proposed is an Antenna Research Associates, Inc. VBC-31J at 38.7 meters.

OTHER Items of Interest


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Last modified January 4, 1998 by Doug Lung dlung@transmitter.com
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