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.

Issues are dated each Monday, although recently I've needed an extra day or two to complete each issue. Articles may be posted earlier if time permits or if there is a major, breaking story.

<<< Back to May 26 - Issue 167

June 7, 1999 - Issue 168 Final Edition

FCC Proposes Service Rules for New 746-764 and 776-794 MHz bands (June 4)
Yesterday the FCC released the full text of the Notice of Proposed Rule Making (FCC 99-97) in the Matter of Service Rules for the 746-764 and 776-794 MHz bands. These frequencies are the former TV channels 60-62 and 65-67. A summary of the rules and a link to the FCC News Release on the Proceeding was provided in the May 17, 1999 RF Current.

The NPRM asks for comment on several issues, technical and non-technical, regarding the use of the spectrum. A key issue discussed is whether services should be regulated under Part 27, which govern Wireless Telecommunications Services, or Part 73, which govern Broadcast Services. The FCC's initial proposal is " to subject these licensees generally to Part 27 of our Rules, which governs Wireless Communications Service. Because Part 27 was originally developed with an architecture designed to accommodate flexible use, we believe it provides an appropriate licensing framework for the common elements of regulation that are applicable to wireless and broadcast services alike." The nature of the service proposed on the channel will determine which rules would be applied.

The NPRM does not propose detailed technical rules, except where they apply to interference, both in band and out of band. Specific technical rules would be taken from existing rules for similar services. On the interference issue, the NPRM states:
"We do not have reliable information at this time on the technical parameters for services that will be provided in the 746-764 MHz and 776-794 MHz bands. Our allocation and designation decision permits the range of uses in the Allocation Table, and we cannot be certain what wireless services will be operating in adjacent spectrum. A broad range of technologies may share this spectrum, and the nature of the services and technologies can affect the potential for interference between licensees using the same spectrum in adjacent service areas. We are particularly interested in potential interference issues should the range of uses extend to full power broadcast service."
The NPRM said, however, "We tentatively conclude that either a coordination or field strength method, when properly applied, can provide a satisfactory means of controlling harmful interference or determining the interaction between systems, although there may be reasons to prefer one over the other in the 746-764 MHz and 776-794 MHz bands."

The FCC proposes limiting effective radiated power in new bands to 1,000 watts. While the NPRM states that broadcast operations may be allowed on these frequencies, this power level would appear to severely limit their usefulness for wide area TV broadcast services.

Licensees in the proposed commercial spectrum would be required "to attenuate the power below the transmitter power (P) by at least 43 + 10 log10(P) watts or 80 decibels, whichever is less, for any emission on all frequencies outside the licensee's authorized spectrum." The FCC outlined NTIA requests for attentuation of harmonics falling within the 1559-1605 MHz GNSS band used for GPS. The NTIA standard would require attenuation up to 90 dB for full power mobile equipment and 75-80 dB for handhelds and portables. Specifically, the FCC said:
"...potential full power broadcast use of this spectrum could pose additional difficulties for the GNSS system. Because conventional full power broadcast stations would operate at powers several orders of magnitude larger than those used by commercial fixed and mobile stations, additional attenuation of out-of-band emissions may be required to protect the GNSS systems. NTIA has recommended, in this case, that an emission limit of -110 dB below the average transmitter power should be included as the proposed unwanted emission limit, including harmonics, for DTV transmitters operating in the 746-764 MHz and 776-794 MHz bands."
NTIA noted that the current DTV mask requires emissions, including harmonics, that are more than 6 MHz from the band edge must be attenuated by this amount.

The FCC's discussion of protection to existing TV broadcast services, both analog and digital, offers several alternatives. Refer to the full text of the NPRM for this discussion. The FCC proposes to adopt rules similar to those in Section 90.545. For analog TV signals, at the Grade B (64 dBu) contour, the required D/U (desired to Undesired ratios would be 40 dBu for co-channel signals and a 0 dB for adjacent channel signals. For DTV signals, the protection ratios for co-channel and adjacent channel signals are 17 dB and -23 dB respectively.

Much more information is available in the Notice of Proposed Rule Making - FCC 99-97, available from the FCC on the Internet in both text fcc99097.txt and Adobe Acrobat PDF fcc99097.pdf files.

FCC International Bureau Makes Updated Rules Available On-Line (June 2)
In Public Notice pnin9105 the FCC International Bureau announced it was releasing, "for the first time on the Internet, an unofficial compilation of selected rules applicable to international telecommunications carriers." The Notice said "The compilation includes the most recent changes adopted by the Commission in its March 1999 order streamlining and simplifying the international Section 214 authorization process and related rules."

The rules are available at http://www.fcc.gov/ib/td/pf/telecomrules.html.

FCC Satellite Applications - (May 27)
Some applications of particular interesting from the FCC International Bureau's Satellite Policy Branch Applications Accepted for Filing (pnin9102.pdf) include an application from Lockheed Martin Corporation for a global regional positioning system consisting of 12 geostationary satellites using frequencies from 1176.45 MHz to 6725 MHz in various bands.

PanAmSat filed an application for a replacement C/Ku-band satellite to be known as Galaxy IV(R) at 99 degrees W.L. and for a similar replacement, to be known as Galaxy X-R, at 123 degrees. Galaxy IV failed in May 1998 and Galaxy X suffered a launch failure in August 1998.

Columbia Communications filed an application to modify its authorization to launch and operate a satellite at 47 degrees W.L.

Echostar requested Special Tempororary Authority to relocate the EchoStar 4 Direct Broadcast Satellite from 148 degrees W.L. to 110.2 degrees W.L., with operation of 28 of the 29 channels continguent on consummation of the assignment of the MCI Telecommunications License to EchoStar 110 Corporation. (The FCC document is available in Adobe Acrobat format only.)

TV - CEMA Forms Committee to Deal with Television Set Safety (May 27)
While most broadcasters and Congressmen are concerned with violence on television, the Consumer Electronics Manufacturers Association, CEMA, is taking steps to prevent violence by television sets.

Specifically, CEMA has formed the Home Entertainment Support Safety Committee. The CEMA Press Release said "This committee, comprised of television and consumer electronics furniture manufacturers, will implement short- and long-term strategies to proactively address the issue of accidents involving falling televisions and home entertainment support units (TV stands and other furniture)." Gary Shapiro, president of CEMA, explained "A goal of this committee is to educate consumers about the safe use of television stands and other home entertainment support units. Educating consumers about the proper and safe use of our products is the right thing to do."

MICROWAVE - First Commercial COFDM Digital ENG truck Deployed at WCVB Boston (May 26)
In a Press Release dated May 26, Adaptive Broadband Corporation, NDS, Wolf Coach and Hearst Argyle Television announced "the first commercial over the air transmission of the new MRC(TM) CodeRunner(TM) radios. The MRC CodeRunner went into service last week at WCVB-TV, channel 5 in Boston. WCVB Director of Engineering, Mike Keller, said "The operational advantages of the COFDM newsgathering equipment raise our live news coverage to a new level. The analog trucks operated reliably only with an unobstructed view. Even then, reflections often made clear reception a problem. Now, even when you can't see the receive site, you can still get a perfect live shot. This new technology can use reflections as a part of the transmission path. We now have the ability to deliver live news from almost anywhere in the city - fixed or mobile - in a way that otherwise couldn't be done."

The CodeRunner operates at 2 GHz, within the pending 12 MHz bandwidth channel plan, using COFDM modulation. See NAB stories in the April RF Current issues for more information on this product.

CORRECTION - FCC TOWAIR Query web address (May 28)
The FCC Wireless Telecommunication's Bureau issued an ERRATUM to Public Notice Released May 26, 1999 concerning the TOWAIR Query availability through the Internet. The ERRATUM corrects the WWW address listed in the original Public Notice. The correct URL for the TOWAIR Query is http://gullfoss.fcc.gov:8080/cgi- bin/ws.exe/beta/genmen/index.hts.

DIGITAL TELEVISION STATION APPLICATIONS - See ap990607.txt for more information
Call (DT) Ch. Licensee Location ERP (kW) HAAT (m) Antenna
KSAZ 31 KSAZ License Phoenix AZ 1000   (mod to change ERP)
WPXW 43 Paxson Washington Manassas VA 80 154 Non-directional


DIGITAL TELEVISION STATION APPLICATIONS - See ap990604.txt for more information
Call (DT) Ch. Licensee Location ERP (kW) HAAT (m) Antenna
KGW 46 King Broadcasting Portland OR 1000   (mod to change ERP)
WBRA 3 Blue Ridge PTV Roanoke VA 7.25 627 Dielectric THP-S2-1-1
WSBN 32 Blue Ridge PTV Norton VA 100 591 Dielectric TLP-A
WMSY 42 Blue Ridge PTV Marion VA 100 448 Dielectric TLP-A


DIGITAL TELEVISION STATION APPLICATIONS - See ap990602.txt for more information
Call (DT) Ch. Licensee Location ERP (kW) HAAT (m) Antenna
WQPX 32 Channel 64 of Scranton Scranton PA 501 364 Dielectric TFU-16GTH C170
KHTV 38 KHTV Houston TX 208 582 Dielectric TFU-18DSC-R CT220SP


DIGITAL TELEVISION STATION APPLICATIONS - See ap990528.txt for more information
Call (DT) Ch. Licensee Location ERP (kW) HAAT (m) Antenna
WZPX 44 Horizon Broadcasting Battle Creek MI 212 305 Dielectric TFU-18DSC 03
WRAL 51 Capital Broadcasting Raleigh NC 1000 629 (increase ERP)
WPXX 51 Flinn Broadcasting Memphis TN 1000 298 Dielectric TFU-18DSC 03
KTXA 18 Par. Sta. Group Fort Worth TX 220 535 Dielectric TFU-24GTH-R S200
WLPX 39 Channel 29 Charleston WV 1000 350 Dielectric TFU-18DSC C170


DIGITAL TELEVISION STATION APPLICATIONS - See ap990601.txt for more information
Applications for License to cover construction permit:
KBHK-DT CH 45 UTV of San francisco, San Francisco, CA
WTAE-DT CH 51 WTAE Heart-Argyle Television, Pittsburgh, PA

DIGITAL TELEVISION STATION APPLICATIONS - See ap990527.txt for more information
Applications for License to cover construction permit:
WFXT-DT CH 31 Fox Television Stations, Boston, MA

OTHER Items of Interest

Next - June 14 - Issue 169


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Last modified June 16, 1999 by Doug Lung dlung@transmitter.com
Copyright 1999 H. Douglas Lung