Broadcasting & Cable
After full-power broadcasters ceased analog operations on June 12 and settled into their final digital TV (DTV) assignments, one of the early findings was that stations with VHF channel assignments were experiencing far more reception problems than their UHF counterparts.
Reception issues were particularly prevalent in Eastern cities like Philadelphia and New York, where the number of stations in close proximity meant that VHF stations had to curtail their power to avoid interference and were often left with signals unable to penetrate into apartment buildings for reception on small indoor antennas.
The FCC has since granted power increases to a number of VHF stations, and let others switch their digital assignments to available slots in the UHF band.
Raycom Media, for example, has switched WLOX, its Biloxi, Miss. station, from VHF to UHF operation, and plans to do the same at its Jackson, Miss., station, WLBT, next month. And WCPO Cincinnati wants to move from its current VHF Ch. 10 assignment to UHF Ch. 22, even though the Scripps Television station has already received a power increase.
"We're still finding areas where the digital signal is not acceptable and is not being received at all," says Mike Doback, VP of engineering for Scripps.
But at least one station, KUAC Fairbanks, Alaska, decided to move in the other direction to solve its reception problems.
Click RELATED for more
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( 3 / 440 )KIDS SHOW US HOW TO BUILD A UHF DTV RECEIVING ANTENNA
Naomi and Noah Miller, the children of FCC OET attorney James Miller, show us how to make our very own zig-zag-style UHF DTV receiving antenna with readily available parts. No preamplifier, no spurs, no Irma Frausto roblem. One clean design. U-Tube video:
http://tinyurl.com/ZigZag-NoPreamp
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( 2.9 / 400 )There are days when you have to wonder about people.
Today I received a call from a business person in the 1500 block of Neubrecht Road. She was mad at the fact that channel 8 on her TV keeps cutting in and out on her TV. For those of you that don't know where this is at, it's roughly 2.5 miles east of our transmitter. Her voicemail stated that we (WLIO) needed to "get it together".I called her back and tried asking some questions. She said she didn't have an indoor antenna, but her brother who is an electronic genius installed the antenna. I asked if she knew the model of the antenna. The answer was no. I asked if it was a UHF only antenna, and I explained that VHF signals are not often received on UHF antennas. In sort of an indignant voice she said "I don't think my brother would have gotten the wrong antenna." In the end there was nothing I could do because she was convinced it was our fault.
I tried to explain there are people in Findlay, B.G. and Sidney watching us with no problem, and she is the only person who complained. That, to me, would want me to check my antenna system. But I don't think she wanted to listen. This is sad because in 99% of the reception cases, by going over what is happening, we can resolve reception problems. This is where the collective sigh comes in.
The irony is, a friend and I were thinking of contacting their company for some work on one of our custom projects. Judging from the conversation, I don't think that's going to happen now. Cue Homer - "DOH!"
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( 3 / 412 )The Central Michigan University Board of Trustees has approved a proposal to submit an offer to purchase WFUM TV in Flint for no more than $1 million.
The television station, currently owned and operated by the University of Michigan, would broadcast from Bay City to the metro Detroit area, Interim University President Kathy Wilbur said the board viewed it as an opportunity to significantly expand the university’s coverage into critical areas such as southeast Michigan.
“It allows us to expand academic programs on the behalf of CMU, especially through Prof Ed,” Wilbur said. “We’re so focused on our enrollment question and retention question, this gives us another avenue in which to pursue that.”
The Board met in special session today in the President’s Conference Room in the Bovee University Center to discuss the television station.
A purchase and interim management agreement will now be drafted so CMU can take over the station as soon as possible.
“This is very common in the broadcast world because of the normal delays in getting approval for a change in ownership through the FCC,” said Ed Grant, general manager for CMU Public Broadcasting.
WFUM is presently owned by the University of Michigan with a transmitter located in Goodrich MI, and has an application to move to channel 28 with 500,000 watts with an antenna at 258 meters (846 feet). The station is likely going to remain an PBS station under Central Michigan University ownership. Goodrich is WNW of Detroit, between Flint and Detroit. One change that probably will happen is a call sign change to better reflect the new ownership.
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( 3 / 304 )This is the WLIO Channel 8 Transmitter as it normally looks...
and with the doors open....
The cabinet on the left is the eight power amplifiers that generate 4,230 watts of power. The power then goes up to the antennas where it's amplified to the 27,500 watts ERP. On the right you see the dual exciters and the controllers.
Click on an image to SUPERSIZE it.
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( 3 / 216 )Samsung has rolled out a chip for the ATSC mobile DTV standard. It combines RF and digital circuits on one substrate to simplify hand held receiver manufacturing:
http://televisionbroadcast.com/article/89072
Fred sez: I think there is a lot of benefit to handheld DTV, but the one thing that bothers me is how soon will it be till we see someone driving down the road watching TV. And you thought cellphones were a distraction?
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( 3 / 174 )I know everyone likes pictures, so here is a few of our operations center.
The picture below is the east half of the master control room. Denny (L) is seated in front of the WOHL ABC 35.1 Master Control switcher. Becky (R) is on the WOHL CBS 35.2 switcher.
Mike is on the west half of the master control room, and is in front of the WLIO NBC 8.1 Master Control switcher. The switcher on the right is the WLIO Fox 8.2 Master Control switcher, which is presently in automation mode.
Jon is in our Satellite Room, which is just north of the MCR. The satellite room is where all the syndicated shows come in and are recorded for playback later. At the present time we record 422 shows a week. Everything is recorded on hard drive for playback.
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( 3 / 186 )PUBLIC NOTICE
Federal Communications Commission
445 12th St., S.W.
Washington, D.C. 20554
News Media Information 202 / 418-0500
Internet: http://www.fcc.gov
TTY: 1-888-835-5322
DA 09-2236
October 16, 2009
FCC’s Office of Engineering and Technology Releases Laboratory Report on Technical Testing of DTV Converter Boxes for Certification under NTIA’s Coupon Program
The Federal Communications Commission’s Office of Engineering and Technology has released a report on tests of digital-to-analog TV (DTV) converter boxes.
The report, OET Report FCC/OET 09-TR-1003, entitled “DTV Converter Box Test Program -- Results and Lessons Learned” (DTV Converter Box Test Report), describes methodologies, results and lessons learned in over 50,000 individual engineering tests that were performed on 136 DTV converter boxes that were submitted for certification as “coupon eligible” by various manufacturers in the period August 2007 to January 2009 and on 17 converter box samples that were purchased from retail outlets through February 2009.
The tests were completed in March 2009. Most of the tests were performed for the Department of Commerce’s National Telecommunications and Information Administration (NTIA) and served as one step in the NTIA’s approval process of converter boxes under the Government’s TV Converter Box Coupon Program and were intended to ensure that all of the boxes certified as coupon eligible passed NTIA’s conservative performance specifications before going on the market.
The DTV Converter Box Test Report, which follows in the tradition of previous reports on tests of television receiver performance by the FCC’s Laboratory, is intended to inform engineers involved in designing DTV receivers, TV broadcasters, measurement technicians, standards developers and the technical community of engineering data on the performance of the converter boxes and of functional and performance issues that might apply to other DTV receiver products as well.
Because information for this purpose is best described as statistical measures of performance, the results are presented without identifying brands or models of converter boxes. Consequently, the report does not provide information that would be meaningful to consumers for selecting a converter box. The testing evaluated a sample of each converter box submitted for certification to check for compliance with NTIA’s technical standards for such devices.
These standards address numerous aspects of radiofrequency performance and other functionalities. To provide additional information on certain other features that are of interest to the technical community, the testing also examined some attributes of the converter boxes that extend beyond the NTIA requirements.
The report indicates that 116 of the 136 converter box models tested by the FCC Laboratory eventually passed all tests to satisfy the NTIA requirements and were offered to the public as coupon-eligible converter boxes, though many required upgrades to software - and in some cases modifications to the hardware - before passing. (The NTIA’s list of 191 approved converter boxes includes minor variants of the 116 models that passed all required tests.)
The report also identifies the initial failures of converter boxes to satisfy NTIA requirements and presents statistics on the RF performance of those that were ultimately approved. It further identifies potential issues for further consideration by DTV standards committees. Those issues include the potential need for add-on channel scan capability and more detailed specification of the requirements for handling future changes to the parental control system through a downloadable rating system.
The report shows that the approved converter boxes exhibited significant RF performance improvements in ability to receive weak signals on VHF channels, ability to reject interference from strong signals on other channels, and ability to process signals received in the presence of severe multipath (of particular importance in indoor reception locations) as compared to DTV receivers that were on the market in 2005 and 2006 (as tested by the FCC Laboratory and reported in 2005 and 2007).
The areas in which initial failures to meet the NTIA standards occurred included parental controls (especially downloadable ratings capability), closed captioning, video modes, daylight savings time implementation and ability to reject potentially interfering signals on certain neighboring channels. In most cases, these failures were corrected by the manufacturer and the box was then re-tested for compliance.
Of the approved converter box models, 72 included an RF pass-through capability to allow reception of analog TV broadcasts on the connected television. The report indicates that those boxes exhibited no significant degradation in DTV reception sensitivity or interference rejection performance relative to non-pass-through boxes.
The testing also found that the approved converter boxes consumed an average of 6.6 watts when operating and 0.8 watts in sleep mode. Because the tested units were supplied by the manufacturers as “production samples,” some of the tests were repeated on 17 “audit samples” that were purchased from store shelves. No statistically significant performance differences were found between the purchased samples and the corresponding samples the manufacturers provided to the certification program.
Finally, the FCC Laboratory’s test experience in previous programs and in the lead-up to and performance of the converter-box program yielded a number of lessons that are documented in the report and that may be of value to others performing such tests. The report states that those lessons include the need to use video containing motion in tests of video modes, the need for daylight savings time tests that extend beyond those of current test software, the impact of automatic-gain-control loops with memory in some receivers, and a methodology to assess the impact of unintended phase noise from DTV signal generators.
For additional information, contact Steve Martin, Steve.Martin@fcc.gov, of the Office of Engineering and Technology, Technical Research Branch, at (301) 362-3000.
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( 2.9 / 167 )According to a posting in the AV Forum, "We (WISE) are scheduled to make the WISE-DT19 to DT18 transition next Thursday October 15th at 12 noon EST. Please let whoever you know that they will need to rescan after the transistion. We will be running crawls to alert viewers."
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( 3 / 138 )Posted in the AVS Forum. Click RELATED for original story.
"The WISE-DT upgrade is complete. We plan on turning on the new transmitter sometime next week. We are allowing time for cable and satellite companies to be ready. Also, there will be crawls starting shortly to tell everyone to rescan their channels after the switchover to RF channel 18."
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