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RF Technology: Doug Lung
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Doug Lung is regional vice president of technology for a major station group. Contact him via e-mail at dlung@transmitter.com.
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How Well Does High VHF Work for DTV?
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by Doug Lung, 4.09.2008
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This month I’ll tackle a topic I’ve been thinking about for some time—what will happen on Feb. 18, 2009, when viewers used to receiving their favorite DTV station on UHF with its 1,000 kW ERP find it’s changed to a VHF channel at much lower power?
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Running SPLAT On Windows
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by Doug Lung, 2.06.2008
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Until recently, the only way TV engineers could obtain an accurate terrain-sensitive plot of a station’s coverage was to buy an expensive program or pay a consultant to create the map. Using the open source SPLAT program, any engineer willing to spend a little extra effort collecting accurate data can create coverage maps that are much more accurate.
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Free and Not-So-Free Maps, Part 1
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by Doug Lung, 11.07.2007
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Accurate elevation maps are essential when calculating microwave paths over rugged terrain or the impact of mountains, hills and even buildings when predicting TV coverage.
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DTV in the House, Part 2
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by Doug Lung, 10.03.2007
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This month, I’ll discuss some ways to achieve higher DTV signal levels. These techniques work without extending the noise-limited contour, thus limiting the interference to other DTV stations.
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DTV in the House, Part 1
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by Doug Lung, 9.05.2007
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The high level of interest in the ATSC M/H mobile/handheld standard and the creation of the Open Mobile Video Coalition indicate TV broadcasters are realizing that the future of off-air broadcasting is more about reaching portable and handheld receivers than transmitting TV to the big screen in the living room, where in most markets, the vast majority of viewers receive programming via cable or satellite.
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Mobile TV Using Existing ATSC Technology
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by Doug Lung, 8.08.2007
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A paper from Triveni, “TV Broadcaster Connecting with the Mobile User,” presented by Richard Chernock at NAB2007 offers an easy way to implement a form of mobile DTV.
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Reviewing RF Technology At NAB2007: Part I
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by Doug Lung, 6.13.2007
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While many manufacturers improved their high-power transmitter lines, I didn’t see any revolutionary changes.
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Determine Real Coverage With SPLAT! 1.2.0
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by Doug Lung, 4.11.2007
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Version 1.2.0 of SPLAT! was released in late December 2006 and includes the ability not only to add azimuth and elevation antenna patterns to the analysis, but to include mechanical beam-tilt as well.
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Evaluating Alternative DTV Distribution
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3.07.2007
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In the January RF Technology column, I looked at three USB tuners that offer an inexpensive way to monitor ATSC signals.
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Signal Testing With USB DTV Tuners
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by Doug Lung, 1.10.2007
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Last year, I provided a quick overview of ATSC USB tuners. This month, I'll provide a detailed comparison of three--DViCO's FusionHDTV5 USB Gold, the AutumnWave OnAirGT tuner and the Pinnacle HD Stick Pro. All tuners include software that allows scheduling and recording programs.
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China's New DTV Standard and DOCRs
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by Doug Lung, 11.01.2006
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RF technology was well represented at this year's 56th annual IEEE Broadcast Symposium. This month, I'll look at two of the many topics discussed at the symposium-the new DTV standard in China, and digital on-channel repeater technology.
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Juggling Antennas for 2009 Requires Planning
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by Doug Lung, 8.09.2006
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The last FCC "use-it-or-lose-it" deadline has passed and most stations with a tentative DTV channel designation on their existing DTV channel, have constructed their fully maximized facilities.
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NAB RF Reflections: A-VSB and DTx
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by Doug Lung, 6.14.2006
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At NAB this year, walking around booths displaying products on video-over-IP and video to handheld devices, it was easy to forget that some people still watch TV from high-power transmitters.
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What to Expect at NAB2006 for RF
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by Doug Lung, 4.12.2006
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NAB2006 this year should be interesting as manufacturers deal with an anticipated drop in demand for high-power TV equipment after the last maximization deadline passes in July and stations wait for the announced end of analog TV transmission in February 2009.
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Is Your Transmission Line Digital TV Ready?
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by Doug Lung, 2.08.2006
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When designing a new DTV transmission facility or planning DTV conversion of an existing analog facility, in addition to selecting a transmitter with sufficient power and an antenna that has the correct tradeoff between gain and elevation pattern, be sure to consider the transmission line.
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Crazy Enough to Build Your Own TV Antenna?
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by Doug Lung, 1.25.2006
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This month, I'll take another look at receive antennas for DTV. My article "Antennas for DTV Reception" in the March 6, 2002 column on antennas for DTV reception was published almost four years ago, yet hardly a week goes by that I don't get a request for Fig. 1, which shows the dimensions for a do-it-yourself UHF TV rhombic antenna.
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FCC Proposes Rules For DTx
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by Doug Lung, 12.07.2005
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This month, I'll examine the FCC's rulemaking on DTx released Nov. 4; two papers presented at the IEEE Broadcast Technology symposium in October; and results of tests on Samsung's new Gemini VSB chipset at CRC Canada.
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How Hard is it To Receive DTV? Part II
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by Doug Lung, 11.09.2005
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Last month, I looked at the technical arguments in the debate over how to determine whether a household can receive a local network affiliate's DTV signal and thus is not allowed to receive a distant network DTV signal via satellite. This month, I'll finish the discussion with more details on the debate and reply comments from Meintel, Sgrignoli and Wallace (MSW) on behalf of NAB.
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So Just How Hard Is it To Receive DTV?
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by Doug Lung, 10.05.2005
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Earlier this summer, an interesting debate developed around the FCC Notice of Inquiry on "Technical Standards for Satellite-Delivered Network Signals" over how to determine whether a household can receive a local network affiliate's DTV signal over-the-air.
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Broadcasting To Cell Phones
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by Doug Lung, 9.07.2005
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This month, I'll focus on technology that will deliver over-the-air TV to consumers, but that won't use broadcast TV transmitters in the United States.
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