Local TV stations KNSD, KUSI, and KPBS on Mt. San Miguel are poised to shutdown their normal analog services June 12 with most of the rest of the nation. None of the three must change channels. KNSD’s Director of Engineering David MacKinnon says current plans have them providing “nightlight” information service on UHF channel 39 until June 26 at full power.

That will leave only low power broadcasters left on analog, along with Mexican broadcast stations like English-language XHDTV 49 Tecate and XETV 6 Tijuana.

A large number of professional broadcast engineers share a background of both listening to distant stations or playing disk jockey, or both. I certainly have.

When I got off work from playing background music at KRCO in Prineville, Oregon in 1973, I tuned across the FM dial to hear multiple signals where none normally existed. A baseball game between Spokane and Phoenix turned out to be originating from Arizona. I put up rabbit ears at home and experienced a massive influx of low-band VHF TV stations from Texas to Alberta on what I learned was the sporadic-E mode of propagation. It turns out that E-layer propagation takes place mostly in May and June, with smaller openings at other times of the year. Due to the angle of reflection, reception of a single E-layer bounce tends to take a signal somewhere in the range of 700 to 1700 miles. Multiple bounces are more rare, but can double or triple that range.

Every May and June now, I tend to log a couple dozen ham stations on the 50 MHz 6 meter band. A casual operator only, I’ve logged multi-hop contacts to Georgia, Hawaii, and a couple in Japan using my rooftop Create log-periodic and 100 watts.

A Limited Opportunity

Starting June 13, the number of full-power TV stations occupying the low-band VHF band will dwindle to a handful, and if you count only those in the E-skip zone, the number of DTV stations most likely received in San Diego will be down to 14. Obviously, these channels will eventually fill with either low-power DTV signals, or the FCC will reassign the band to other uses like the commonly discussed audio services. So I consider this a limited opportunity to enjoy relatively interference-free DXing.

Actually, the transition isn’t that simple. A number of analog stations will remain on the air for up to one month broadcasting “nightlight” service to help uninformed over-the-air viewers get the information required to transition to DTV. Many of those stations will be on low-band VHF.

Then there are the remaining TV stations in the skip zone from western Canada, central and northeastern Mexico, and low-power channels that may add enough noise to make 8VSB reception impossible during certain E-skip events. And did I mention low-band VHF analog channels 3 and 6 from Tijuana remaining on-the-air?

A listing of the 14 candidate DTV stations is below. I did not count low-power analog broadcasters, nor one 270 watt Jackson, Wyoming station with a null to the southwest. I did not list double-hop stations, but if you monitor long enough, you are likely to catch one or more. The best way to learn of sporadic-E clouds is to monitor the VHF-DX.net real-time map that accumulates the “spots” of operating hams. The MUF, or Maximum Usable Frequency, tends to rise to a peak that may never approach channel 2 VHF, but can, on occasion, extend above the FM band. I have occasionally been made aware of big openings by having our channel 6 viewers complain of big black lines and heterodyne audio tones.

If you don’t care about high definition, you can use one of the new, inexpensive DTV converters. The Zenith and Insignia (Best Buy house brand apparently also manufactured by LG Electronics) get high marks for sensitivity and allow manual channel entry. The Magnavox TB100MW9 is able to scan a single channel at a time and can freeze a frame for photographing. The Accurian HDTV receiver box can meter signal strength of a single channel even when it is below decoding threshold, which makes it very useful for DX’ing. The RCA brand is consistently criticized for its lack of sensitivity. Actually you can check the list of converters reviewed by MSTV for one with extra dBs of sensitivity, quick scanning, and easy channel ADD.

If you have a directional VHF antenna, rotator, and DTV, you should be good to go. Computer capture software or a digital camera set at 1/15 second exposure will allow record keeping.

Data for this table came from the latest FCC Table of Allocations and Hammett and Edison coverage maps. Email me with any changes.

As part of a nationwide cut of 590 employees, nearly half of the local Clear Channel IT and broadcast engineers were let go Tuesday, April 28.

While local management couldn’t name names, SDRadio.net wasn’t as discreet. The website lists sports remote engineer Rick Hill, IT specialists Steve Smith and Alex Fajerman, and veteran engineer Ron Foo, and facilities-utility tech Rich Tschiegg. A number of employees from all departments took the hit in San Diego. Ron Foo had been through several mergers, having worked as engineer for the original KGB-FM/KPQP (now KLSD) in the 1990s. At that time, he was very active with SBE, including publishing the chapter newsletter. Layoffs are not unique to Clear Channel Communications in San Diego, but the proportion cut from Engineering, nearly half of the total employed, is significant for the team.

All major broadcast TV and radio stations have reported some cuts in technical personnel during this recession, and many are down to lower levels than ever before. Some crews say they can now only respond to the "crisis of the day."

(From member Mike Curran)

Alex Brawner and I bumped into this 4’5″ example up on our repeater site near Escondido on April 20. This one is a red diamond rattlesnake. They are not usually aggressive, and some may not rattle when encountered. However, the venom is potentially dangerous to humans, so it should be treated with caution and respect. They scared away easily with loud noises and showers of small stones or gravel.

The last resort would be to KILL them! They perform a free service by keeping those, insulation chewing, power supply nest building, and Hantavirus carrying vermin out of our facilities.

So heads down as you walk and don’t reach where you can’t see.

Click HERE to see full size photo. 

This was a very different convention. I’ve attended almost every year since 1983 when RCA and Ampex ruled, but this year’s was one to remember. Some estimated attendance down 30%, others as low as 50%.

Since official attendance is based on registration and not “door count,” we may never know. But let me tell you, there was plenty of room in the aisles and in booths. I got to touch equipment and talk for up to an hour with attentive vendors. At Grass Valley. And Sony. I am not exaggerating. Lunch meant getting a table and relaxing for a while. Seriously. Rene Savalle of ComtechTV remarked that the air conditioning even seemed to keep up this year.

Leon Messenie of KPBS said, “I thought the show was just right as an end buyer. I wish they would have condensed the halls a bit. It seemed they still wanted to have the appearance that NAB needed all the halls. There were so many places to sit down and rest which was nice but it also kept the show spread out.

Sales representative Alicia Reed of JVC summed up the opinion of other vendors, “A seemingly large ratio of the attendees we talked to also seemed to have budgets and intentions to purchase this year, which was encouraging.” Stephen Milley of TV Magic added, “It resulted in a more educated and qualified attendee which led to more sophisticated conversations about projects, technology, and new products as less time was spent educating attendees on the basics of video.” We saw fewer students and non-technical managers, and the proportion of foreign visitors seemed higher because of the lower numbers of domestic visitors.

Another recurring theme this year was bragging rights for attending cheaply. Many of us spent at least some of our own money, either to extend the stay or to go at all. CBS Radio told its employees, “Your time, your dime.” People compared room rates. “$45 a night and not a bad room,” one workmate said. I reserved too early at $79 a night, seeing it go for $47 two months before the show. But this was for a room that went for $140 last year. Flights on Southwest Airlines went for $49 to $75 per seat each way.

Similarly, exhibitors most likely either canceled or toned down their parties and hospitality suites. The famous annual Grass Valley party didn’t happen. Avid had a band and served drinks, but no food. A few took place anyway.

What was hot? In TV, 3D exhibits with cardboard glasses were everywhere. They used interlaced polarity LCDs, so the technique finally dispensed with red/blue lenses or active glasses that alternately shutter between sides. The color appeared much more natural.

We also saw smaller, lighter HD cameras. Broadcasters are finally rejecting in large numbers the shoulder-mounted behemouths in favor of small, far less expensive handhelds with disc or flash memory media. JVC showed two models, Sony showed a studio control for its popular, small EX3 XDCAM.

Grass Valley showed its new Kayenne switcher that seemed to finally marry technologies from its European and U.S. engineering facilities.

Sometimes you just wonder if a problem will ever be solved, though. Scott Stinson of KPBS and I saw booths where lip sync errors on video were impressively detected and measured, but not corrected for fear of getting it wrong. We also both thought we would see numerous exhibits of thin, power saving LED HD monitors, and we didn’t. Plenty of monster size outdoor LED monitor/heaters, though.

With the revolutionary changes caused by DTV, HDRadio, and BAS ENG nearly over, some booths seemed like the calm after the storm. Dennis Pieri of Bext attracted some attention with his exhibit of video over their next generation FMeXtra digital subcarrier, but otherwise, traffic was slow. We saw the same thing at other transmitter and antenna vendors.

RadioWorld Magazine named several well integrated audio-over-CAT5 studio systems among their Cool Stuff awards for this year. Burk’s PPM assurance monitoring and Sage ENDEC’s next generation EAS equipment caught my attention.

Some vendors grumbled about the high cost of the show and whether it should stay open Thursday at all. Indeed, NAB organizers largely ignored economic conditions themselves, opting to occupy four days of floor activity and four huge halls, and charging fees unadjusted for the downturn. Quantel and Cisco were conspicuously absent this year, and Apple did not return after leaving last year.

A few changes took us by surprise. The home-grown Tiernan name disappeared with Radyne’s sale to Comtech last year. Jack Herbert left that company to sell processors for Fujitsu. Val Reynolds left Sony for Omneon.