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.

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February 14, 2000 - Issue 201 Final Edition

DTV - ATI Announces New Technology for DTV on PCs (Feb. 14)
ATI Technologies, Inc. announced it was working with Conexant, NxtWave and Ravisent to develop technology for receiving and decoding DTV signals. The new technology is basted on ATI's RAGE 128 PRO display chips and add-in boards. The RAGE 128 PRO chip includes an integrated iDCT decoder with motion compensation capability that enables decoding and display of all 18 ATSC HDTV formats at full frame rates. ATI worked closely with Microsoft "to ensure full interoperability with operating system software."

Conexant's Fusion 878A PCI video decoder is used to handle NTSC, PAL and SECAM analog video decoding and to take the MPEG transport stream from the 8-VSB demodulator chip over the PCI bus to the host CPU. Ravisent's Software CineMaster(tm) is used for MPEG decoding. The ATI release said "CineMaster incorporates newly-developed, proprietary algorithms enabling the decoding and playback of all eighteen digital television formats specfied by the Advanced Television Standards Committee (ATSC) including all HDTV formats.

The ATI RAGE 128 PRO sustem uses NxtWave Communications NXT2000 demodulator chip for demodulating over-the-air DTV using 8-VSB and cable DTV using 64/256 QAM. Matt Miller, President and CEO of NxtWave said, "We are please that ATI, with its record of technical leadership and innovation, has selected NxtWave as its partner for digital demodulation of DTV signals. We believe that digital TV on a PC will be a killer app. The NXT2000 is the first chip to give the consumer the robust reception needed for the PC, The NXT2000 provides the technologies to ensure DTV reception anywhere signals are available."

More information on ATI's DTV solution is available in its Press Release. The press release did not say when the products will be available.

FCC Adopts Changes to Rules for Microwave Services, Proposes Additional Changes (Feb. 14)
The FCC released a comprehensive Memorandum Opinion and Order and Notice of Proposed Rule Making on the reorganization and revision of Parts 1, 2, 21, and 94 of the FCC Rules and the Rules to establish a new Part 101 governing terrestrial microwave fixed radio services (WT Docket 94-148), Amendment of Part 21 of the Rules for Domestic Public Fixed Radio Services (CC Docket 93-2), Amendment of Part 101 of the Rules to streamline processing of microwave applications (WT Docket 00-19) and Petitions for Rulemaking from the Telecommunications Industry Association and McCaw Cellular Communications.

Of particular interest to TV broadcasters, this Memorandum Opinion and Order and NPRM addresses a petition by the Telecommunications Industry Association (TIA) proposing rule changes to Part 74, Television Broadcast and Auxiliary Service, to "permit transport of digital transmissions over point-to-point microwave frequencies in that service." Also, the FCC seeks comment on what approach to take when there are different technical rules for different services using shared frequency bands. In particular, the FCC looked at the shared bands at 2450-2483.5 MHz, 12700-13250 MHz and 38600-40000 MHz where there are frequency tolerance or EIRP conflicts beetween the rules in Parts 74 and 78 and those in Part 101. The 2450-2483.5 MHz band is also shared by Part 90 services. In this spectrum, Part 101 fixed microwave users are required to coordinate with other fixed microwave users, broadcast auxiliary users must use local coordinators, and Part 90 users are not required to coordinate. One approach suggested is to state that where conflicts arise, the more restricture rule will apply or, alternatively, conform the technical standards for all rule parts.

Some of the significant decisions in the Opinion and Order include:

In the NPRM portion of the release, the FCC requested comment on:

The FCC also seeks comment on several proposals addressed in Petitions for Rulemaking:

Comment was also requested about possible technologies for terrestrial microwave users concerning a new proposal for frequency resuse in the 12.2-12.7 GHz band.

The Memorandum Opinion and Order and Notice of Proposed Rule Making is a large, complex document. The full text is available on the FCC web site as a Microsoft Word file - fcc00033.doc or as a text file - fcc00033.txt. Please refer to it for complete information.

DTV - Brazil's ANATEL Rejects 8-VSB for DTV in Preliminary Report on Latest Tests (Feb. 11)
The preliminary report by the Associacao Brasileira de Emissoras de Radio e Televisao - (ABERT) and the Sociedade Brasileira de Engenharia de Televisao (SET) said initial DTV reception tests showed COFDM performed much better than 8-VSB modulation. Within 10 kilometers of the transmitter site. Using COFDM, reception was possible at 100 percent ot the test sites. Using 8-VSB, reception was possible at only 980 percent of the sites. The report said COFDM is more robust in reception and has the capacity to transmit HDTV. COFDM also worked better indoors and in moving vehicles.

The coordinator of the SET/Abert group, Fernando Bittencourt commented that the ATSC 8-VSB technology would have to improve to match the quality of the other two modulation systems tested (DVB-T and ISDB-T). However, he added that Anatel was not excluding the North American standard, but it must present better results to continue in the selection contest.

The test report was presented to the Renato Navarro Guerreiro, president of the Brazilian National Agency of Telecommunications - Anatel on February 11th. Testing will continue until March 30.

More information is available on the Anatel web site, although it is in Portuguese. The February 11 Release on initial test results is available in Acrobat (PDF) format, as is the February 10 release outlining the testing. To translate selected text from Portuguese, use Babelfish. Babelfish was used to translate the releases for this report. Look for more information on the testing in future issues of RF Current.

INDUSTRY - Harris Agrees to Sell its TV Antenna Business to Dielectric (Feb. 9)
Harris Corporation announced it will sell its TV antenna business to Dielectric Communications. The Harris Press Release said the sale included the antenna test range in Palmyra, Missouri. This is considered one of the best antenna test ranges in the United States. Dielectric intends to continue operation at the Palmya site with the Harris commercial broadcast antenna employees.

Dale Mowry, vice president of television systems for Harris Broadcast Communications Division, explained the sale, saying
"Harris decided to sell its TV antenna business after intense evaluation. It became apparent that the technical discipline, front-end sales process and customer support required to be a leader in broadcast antennas are measurably different than those required for our core transmitter business. Although our antenna business focused on innovative technologies, it was diverting attention from our much larger transmitter business. For this reason, we decided to look for a buyer with antennas as its core business, an interest in expanding its product line, and a commitment to continued growth. Dielectric is that buyer."

INDUSTRY - EMCEE Signs Letter of Intent to Acquire Assets of Advanced Broadcast Systems, Inc. (Feb. 8)
EMCEE Broadcast Products, Inc. announced it had signed a Letter of Intent to acquire the assets of Advanced Broadcast Systems, Inc. Advanced Broadcast Systems (ABS) manufacturers high power UHF TV transmitters. Recently ABS introduced a line of digital TV transmitters using IOT power amplifiers and a new crowbarless switchmode power supply. EMCEE is a manufacturer of low power TV and MMDS/ITFS transmitters and has developed equipment for one-way and two-way 2-4 GHz wireless Internet, video and voice services. EMCEE offers an inexpensive one-tube 2.5 kW "Transition" transmitter for DTV.

OTHER Items of Interest

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