CBS and Clear Channel Partner on Soledad Antenna Project

A new multiplexed FM antenna on KGTV’s Mt. Soledad site is open for business and radiating. John Rigg, San Diego market Director of Engineering for Clear Channel Communications says that his stations KMYI 94.1 MHz, KIOZ 105.3 MHz, and CBS Radio’s KSCF 103.7 MHz have been on the 4-port system since April 5 of this year.

ERI designed and built the system, an SHPX-10AC-HW center-fed 10-bay half-wave spaced array with approximately 5 dB gain. John says “ERI was chosen because their SHPX series antennas present less weight and wind load than comparable antennas from other manufacturers. Their combiner is more modular and easier to install in tighter places, specifically the attic space above the transmitters.”{mosimage}

Clear Channel and CBS have partnered before on a similar project on the site.  KIOZ and KSCF have been combined on an adjacent tower for several years. The main tower owned by McGraw-Hill Broadcasting now hosts the new community antenna. Two site developments motivated the participants to build the antenna: the need for a reduction in RF radiation at ground level due to a new residence to the west of the site, and the steep rise in rent at neighboring towers owned by Midwest Television, KFMB-FM/TV.

They now occupy a position just below the tower top, below the KGTV channel 10 antenna, but sharing the aperture of the KGTV-DT UHF array. John says that they did extensive modeling before construction to assure little interaction between those antennas. In fact, the modeling resulted in the fabrication of antenna mounting brackets out of non-conductive materials.

The quest for the master antenna began after completion of a new home two lots away, adjacent and northwest of the neighboring fire station on Via Casa Alta. Hammett and Edison studied ground level radiation at the home and determined a particular hot spot at a steel column that wasn’t going to go away unless a substantial rearrangement of radiators took place. RFR laws state that any contributor of more than 5% of the maximum permissible exposure (MPE) is equally responsible for mitigating the problem regardless of the contribution percentage. Since KFMB and its tenants KIFM and KYXY were farther away and had just completed their new combining array with low downward radiation values, they were let off the hook. Two other Soledad FM broadcasters using the UCSD-owned tower, KUSS 95.7 MHz, and KLQV 102.9, have had to temporarily decrease power to meet the public RFR guidelines.

In February of 2006, the FM broadcasters on the KGTV and UCSD towers agreed to decrease power temporarily by 25% each. The one exception was Super Class B grandfathered, normally 100 kW, KMYI 94.1 (“Star 94”), which due to a null at the site in question did not have to decrease power at all. KMYI was added to the combiner system to allow the new antenna to be installed on the KGTV main tower removing its weight and wind load contribution to the overall tower loading.

Each of the Clear Channel and CBS stations obtained construction permits in mid-2006. ERI delivered the antenna system in late March this year, and crews were waiting to erect it immediately.

John Rigg reports that their expectations regarding both the increased performance of the antennas and their decreased downward radiation have exceeded expectations. They’ve now got KMYI at 77 kW ERP and he’s happy with the coverage. He says the new antenna is higher and the pattern is cleaner than before, so they need less power now to reach their licensed contours.

For his part, Mike Prasser, San Diego Market Director of Engineering for CBS Radio, appreciates John taking the role as project leader. “He should be commended for how smooth the project went. As for the results of the project, I am extremely pleased.” He’s satisfied that they’ve mitigated the RFR issues and says that he is now working hard to get KSCF broadcasting in HD-radio, which should be up in June.

KPBS-FM Applies for Move to Soledad

KPBS-FM 89.5 MHz filed with the FCC an application to move their transmitter to Mt. Soledad and increase power to 26 kW ERP from their current 4.4 kW.

The application names the KFMB-FM-TV transmitter site as its new home, but does not address two sticky issues about the site. First, RF radiation at the site can be increased only with very careful modeling, coordination, and measurement due to the proximity of homes. Second, the current community FM antenna was specified and built with a low frequency limit of 94 MHz, and the tower is considered fully loaded. KFMB RF supervisor Rick Bosscher said they are discussing with KPBS a plan to overcome those obstacles.

San Diego State University and the KPBS Foundation have long wanted to move to Mt. Soledad for its obvious increased coverage in North County and northern suburbs where a high concentration of its affluent demograhic resides. In fact, KPBS-FM currently runs most of its informational programming with the stereo pilot off to help boost its coverage.

The FCC recently cleared the way for the relocation when it rejected filings by Televisa, owners of XETV channel 6, against the power increase application of KSDS. In that case, the FCC said that international treaties did not specifically address FM-to-TV channel 6 TV interference, so KSDS was free to raise power regardless of affects to U.S. reception. Exhibits filed with the KPBS application cite that FCC ruling to support their increased channel 6 interference zone.

Disclosure: The author is Director of Engineering for Bay City Television, a U.S. subsidiary of Televisa and the marketing and news operations arm of XETV.

March 2007 Meeting – Dielectric

Thanks to all for attending. 20 local radio group engineering executive and friends ate a fine lunch and heard a few words from Al Jason of Dielectric on their RF Scout and tower LED beacon products. Craig Caston of Salem Communications won the Sangean HD-Radio provided by SCMS. Thanks to Doug Tharp for the lunch and radio!

FCC Enters Consent Decree with KFMB-TV Over Captioning Fine

The FCC has entered into a Consent Decree with Midwest TV, owners of KFMB-TV in San Diego, canceling a $20,000 Notice of Apparent Liability issued after the station was accused of failing to make emergency information available to people with hearing disabilities during the October 2003 wildfire news coverage.

In the decree, KFMB-TV admits no wrongdoing, but would agree to an Emergency Visual Presentation Policy set for staff members that will be overseen by the News Director. The policies require timely Closed Captioning or open captioning of aired emergency information through any means available, including “handwriting on a blackboard.” The decree also requires KFMB-TV to make an $18,000 “voluntary contribution to the U.S. Treasury.”

The FCC also issued NALs to KUSI and KGTV in 2005 of $25,000 and $20,000 respectively. To date, those Notices have not been settled.

Making Waves: DST Means Work for You and Me

On March 11, 2007, Daylight Savings Time starts earlier than last year. Congress moved the date with a simple vote. Now you and I have to do all the dirty work to make our computerized world fall into place. Are you ready?

When I was 15 and enthused about ham radio, I bought from Allied Radio one of those 24-hour wall clocks and set it for Greenwich Mean Time. Yeah, I was that geeky. What that clock showed me is that all the fuss about time zones and daylight saving time is completely unnecessary. Why couldn’t the whole world run off one time and change their local school and work times to whatever they wanted? Does it really matter if they’re going to work at 0800 in London and we’re going to work at 1800 in San Diego? Instead, governments and corporations spend enormous resources tracking zone boundaries and daylight saving periods. DST serves only as a way to change the numbers on the clock, and is more meaningless the closer you get to the equator where sunrise and sunset times don’t change much. If safety and conservation are important at the upper latitudes, why don’t we just change the starting times of the school or work day to suit the daylight available?

In 1973, they messed with daylight saving time briefly because oil supplies were squeezed. They wanted more daylight in the afternoon so that we didn’t run so many lights at work. But what I remember is that we were suddenly getting up in utter dark, running the heat and lights at home an hour earlier than before. The problem was that at the 45th parallel, there was only so much daylight. At the time I worked at a small daytime only Class IV AM station in Oregon, and during December and January I would sometimes work weekends from the 8:30 AM sign-on to the 5:30 PM sign-off. According to Wikipedia, studies of the effects of DST have variously concluded savings of energy and traffic deaths as well as loss of savings to economic efficiency and increased energy peak loads at sunrise.

On March 11 this year, we’re changing from the usual early April changeover to DST to March 11. The United States change is part of the Energy Policy Act of 2005. Again the justification is to synchronize the workday to the hours of daylight available so that we are less dependent on Middle East oil.

The international ramifications are interesting. Canada decided to adopt the U.S. plan to move DST; Mexico did not. For the first time that I can remember, Tijuana will be in a different time zone from San Diego from March 11 until April 1. My station, XETV Fox 6, will be in the uncomfortable position of advertising programming times to its majority U.S. audience in Pacific Daylight Time, while the country of license observes Pacific Standard Time.

You may have work to do in preparation for March 11 this year. If you run Windows XP or Vista on the internet, you should be able to download their normal maintenance update to change the automatic DST switch date. If you run a machine isolated from the net, you’ll have to schedule a download or just change the time zone of the workstation in question.

It turns out that the Dallas Semiconductor real time clock (RTC) chips that control time in many computers have hard-coded DST changeover dates so that can’t be overcome except by manually changing the time or GMT offset.

You can program Macintosh computers to change automatically on the correct dates by editing the /etc/localtime file. Instructions can be found here. has a clock howto with DST information.

If you depend on Java runtime applications, see Sun’s DST FAQ. It appears that if you accept the Java RT update being pushed to your workstations this month, you should be okay.

You’d do well to look around for time-dependent systems that may need your intervention. Some vendors are offering software upgrades to automate the GMT offset at the new time. Triveni, for example, is asking $500 to upgrade its PSIP management software that includes revised DST changeover dates. If you have a collection of similarly needy boxes around your broadcast facility and you can’t get away with simply changing the GMT offset yourself, this time change is going to cost you.

Society of Broadcast Engineers, San Diego