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 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.

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.

According to the FCC citation, the San Diego office received a complaint of a signal on 1610 kHz in Oceanside. On November 2 last year, investigating agent Bill Zears found on Canyon Drive a Part 15 compliant 3 meter long antenna, but a 30 meter ground system. The FCC named Iglesia de Dios Ebenezer ("Ebenezer Church of God") as subject of the citation.

Digital radio broadcasting seems to be catching on in San Diego despite the high cost of installation and low listenership. Ibiquity Digital Corporation, sole provider of the FCC-approved IBOC system, built into its growth plan heavy financial incentives, including lower or no license fees for early adopters. Large groups like Clear Channel endorsed the move to IBOC, too.

Ibiquity is working the backend, too. We’re beginning to see and hear commercials boosting HD Radio and mentions of commercial-free subchannels. And radios with digital capability are showing up at Radio Shack, Best Buy, and Fry’s.

So what’s going on in San Diego radio?

Here’s a table of San Diego HD-Radio stations, courtesy of Ibiquity:

89.5	KPBS-HD1	FM	News/Talk/Info	San Diego State University
89.5-2	KPBS-HD2	FM	Groove Salad from NPR	San Diego State University
93.3	KHTS-HD1	FM	Top 40	Clear Channel Radio
93.3-2	KHTS-HD2	FM	Mega Spanish	Clear Channel Radio
94.1	KMYI-HD1	FM	Hot AC	Clear Channel Radio
94.1-2	KMYI-HD2	FM	Variety	Clear Channel Radio
95.7	KUSS-HD1	FM	Country	Clear Channel Radio
95.7-2	KUSS-HD2	FM	New Country	Clear Channel Radio
97.3	KSON-HD1	FM	Country	Lincoln Financial Media
101.5	KGB-HD1	FM	Classic Rock	Clear Channel Radio
101.5-2	KGB-HD2	FM	All Dave, Shelly & Chainsaw	Clear Channel Radio
105.3	KIOZ-HD1	FM	Rock	Clear Channel Radio
105.3-2	KIOZ-HD2	FM	Rock	Clear Channel Radio
107.1	KSSD-HD1	FM	Spanish/CHR	Entravision
600	KOGO-HD	AM	News/Talk	Clear Channel Radio

I asked three San Diego engineering managers about their HD-Radio projects:

Leon Messenie, KPBS

When did you first hit air?

July 29, 2005

What is on your subchannel?

Groove Salad – KPBS’s secondary digital channel. Groove Salad, a 24-hour music station, is a partnership between National Public Radio and Soma FM; and the result is, well, “groovy.” (From our WEB site, not my wording)

Any notable project stories?

The one thing that sticks in my minds was the first morning we were digital. The newscast came up to the point where we cue the traffic report and there was nothing but silence…dead air…. It seems that none of us Engineering or Programming types thought about the newly induced digital delay in the analog signal. This is done to align the analog and digital program streams for a seamless switch between them. This delay is about 8 seconds.

So here is what happened: The Traffic service listens to KPBS-FM off air. When they heard their cue it was already 8 seconds past the real point when they should have started talking. This confused them so much they just stopped talking for the entire report. The Engineering cell phones lit up like a Christmas tree. Needless to say emergency orders for dedicated mix minus phone lines between KPBS and the Traffic office were installed. I am just glad the Traffic service did not have a helicopter….

Recommended receivers?

Not that I recommend them but we use the Boston Receptor HD desktop receiver. They work pretty well with an outside antenna.

Are you considering a closed service for your reading service?

In May 2006 KPBS-FM was part of a test with NPR to test what is being called the extended digital service. We put the KPBS Radio Reading service into this area and then compared the sound quality and reception to that of the analog Sub Carrier receiver. This test was presented at the IAAIS conference at a hotel in Mission Valley. The Mission or as we in radio call it Missing Valley hotel was the perfect place to test this. In a room with about 150 people we listened to first the analog SCA receiver. The sound quality was terrible and you could barely hear the KPBS Radio Reading Service. When we switched the room audio over to the audio from the digital feed the room of people just gasped. The sound was perfect. It was very cool to be a part of something that was such a success. Work is being done now to make this a closed system in order to broadcast Radio Reading Services around the country without violating copyright laws.

John Rigg, Clear Channel Radio

When did you first hit air?

The Clear Channel San Diego stations were on in May of 2006, with the exception of KGB and KOGO which were on in early 2005.

Any notable obstacles?

No two installations were the same, even though the application for HD is software written by Ibiquity, manufacturers integrate differently and apply their own GUI to the exporters and importers.

Any warnings?

Planning, Planning, Planning.  If someone has already done this in your group, ask lots of questions, no need to re-invent the wheel.

Recommended receivers?

I have a JVC KDR1 in the car. It’s a great radio, no RDS on the analog though. I’ve heard great things about the Sangean Component Tuner although I’ve not personally seen one.

Is your group adding more HD-Radio stations?

Clear Channel is currently adding stations to the digital offering. I’m not sure of the schedule, but hey, Tucson just did an install.

Eric Schecter, Lincoln Financial Media

 

What stations have HD-Radio broadcasting? What format?

KSON-FM has country on HD-1. We don’t have an HD-2 yet

When did you first hit air?

December 22, 2006, just in time for Christmas.

Any notable obstacles, funny stories, warnings?

Yes, several. The obstacle that was eventually overcome was getting the data to the Harris Flexstar Exciter from the studio where the Exporter (fancy name for a Linux box with soundcards) lives. We use 7 of 24 time slots in a T-1 Intraplex  multiplexer to accomplish this. It appears that the the module adaptors that present a 10 Base T interface only operate at half duplex. In the end, we used a hub rather than a switch at the studio end, and everything seems happy.

In the warning department, first some background: Our transmitter is a Harris HTHD+ and it utilizes a 4CX20000C tube biased AB1 (sort of) to make 18kw transmitter power output (TPO). The FM+HD signal combining occurs in the Flexstar Exciter. This is known as low-level combining. In order for the transmitter system to make spectral compliance, the exciter uses RTAC, or Real Time Adaptive Correction. While you can get away with some VSWR on a regular transmitter, a hybrid digital system really needs to have a flat transmission system (antenna, feedline, fittings, switches) to achieve optimal performance. We have work to do to optimize a system that is about 25 years old.

Recommended receivers?

I’ve evaluated the Boston Acoustics Receptor. With a good antenna, it’s a good performer. With a short piece of wire close to the radio, the display electronics tend to de-sense the receiver, and it’s as deaf as rocks. BA is now supplying folded dipole antennas based on NPR Labs tests. It receives both AM and FM. There are some good hidden menus for the experimenter in all of us.The price point for this fine sounding radio is $299.

I’ve also evaluated a professional tuner by ADA. It’s actually two tuners in one chassis, and is made for tech centers in the stations. It will do both AM and FM HD, displays RDS and HD PAD data, and is a finer performer. Price tag is about $3500.

Do you plan to outfit your other stations?

Yes, KIFM and KBZT.

Mike Prasser, CBS Radio

Which of your stations have HD Radio?

Currently neither of my stations in San Diego are broadcasting HD. We are looking at second quarter of this year for both. The HD2 formats have not been finalized.

Recommended receivers?

Most of the receivers on the market are good. The most exciting thing that I saw at CES last week was a company called Sideport. They have created a single HD chip that contains all of the components needed for HD with a much lower current draw for $20. Currently there are two chips needed one at $15 and one at $20. So this make HD Radio smaller and cheaper to make.