In San Diego, they're bringing down the curtain on 60 years of broadcast history just before midnight tonight. 

KFMB-TV, a pioneer television station that first took to the air on May 16, 1949, will switch off its signal on Channel 8 for the last time. The station, a CBS affiliate, will pull the plug in the middle of "Late Night with David Letterman."  But KFMB-TV isn't going out of business; it's one of four San Diego stations changing from analog transmission to digital under federal rules that will free up the airwaves for other purposes.
 
All told, 421 U.S. television stations will sign off analog broadcasts tonight, affecting only viewers with who get their television on conventional receivers the old-fashioned way: over the air, through antennas.  Previously, 220 other stations in Hawaii, Wilmington, N.C. and Chico-Redding, Calif. made the changeover. Customers who subscribe to cable or satellite TV won't notice any changes at all. 

Some not prepared 
Still, the outfit that brings you the ratings, the Nielsen Co., estimates that 6.5 million homes nationwide are unprepared because they don't have newer digital sets or haven't purchased converters for their older TVs.  (In San Diego, the largest television market with the majority of stations terminating analog broadcasts tonight, it's estimated that 65,000 households receiving over-the-air TV are not ready for the transition.)
 
The government wasn't ready for the transition either.  A program to give people $40 rebate coupons for converter boxes ran out of money, leaving millions of consumers in limbo until Congress voted to allocate more funds.
 
The government also extended the deadline for a complete switchover until June 12 because of all the confusion surrounding the change. But it left a loophole for broadcasters who complained about the high cost of running analog and digital transmitters simultaneously. 
 
In many cities, the Federal Communications Commission gave broadcasters the option of switching to digital on the original changeover date of Feb. 17 as long as one major network affiliate in each of those cities kept the analog signal going until June.
 
So, in San Diego, that honor falls to KNSD, a station owned by NBC.  Across the country, all network owned-and-operated stations have agreed to a stay of execution for analog TV until the June 12 date.
 
"This is not just about whether people can watch their favorite reality show," said acting FCC Chairman Michael Copps in a written statement.  "It's about whether consumers have access to vital emergency alerts, weather, news and public affairs."

Digital limits
But will they?  In some fringe areas where the old analog signals were marginal, viewers may find that even with a digital converter, there may be no reception whatsoever or reception only on some channels.  That's because digital signals don't always travel as well as analog around obstructions like hilly terrain or tall buildings. Consumers who were able to get by on indoor "rabbit ears" antennas may now have to spring for the cost of installing more powerful rooftop antennas.
 
In San Diego, Gary Stigall, a longtime TV engineer, said he thinks the impact could be minimal because  "93 percent of the people here have cable, meaning they won't be affected."  But 7 percent of the audience is still a fairly sizeable number.
 
Tomorrow morning, the FCC plans to have call centers up and running to answer consumer questions about the transition as some people who didn't prepare for the digital TV transition wake up to blank screens on most of their old channels.  "We are trying to make the best of a difficult situation," the FCC's Copps said.
 
The number is 1888-CALL-FCC.  They're expecting plenty of public response.

 I blame Swanson.

When the venerable American food company rolled out its latest product in 1953, two household appliances – the freezer and the television, were becoming commonplace. The marriage of convenience between the two resulted in a bastard progeny - the frozen TV dinner. 

Marketed as a way for Americans to enjoy their meals while they basked in the warm glow of the cathode rays emanating from their television sets, the Swanson TV dinner was an instant hit. Nearly four generations on, the sins of Gerry Thomas (the man credited for inventing both the product and the name for Swanson) are now being visited upon media-saturated Americans everywhere. 

Televisions in eating establishments are as ubiquitous these days as battered stock portfolios. What started as a sensible business model for owners of sports bars and pubs to lure more couch potatoes out of their dens, has devolved into a trend more invasive than any fungal infection.  

They're everywhere.

Airports. Check-out lines. Waiting rooms. Then, the final straw: restaurants. The National Restaurant Association, in a 2007 survey, estimated that 69 percent of casual dining establishments, and 50 percent of fine dining establishments offered televisions for customer entertainment. Make it stop. 

'Teachable moments'
Don't get me wrong. I like television, and not just because it pays the mortgage.  I'm a broadcast journalist. 

Television fired my imagination as a child, and I doubt very much I'd be in the business I'm in now had I not come of age bearing TV-witness to momentous events from my perch on our living room floor. 

Neil Armstrong's "giant leap for mankind" forms one of my earliest childhood memories. Vietnam, Watergate, Hank Aaron breaking Babe Ruth's home run record, the Iran hostage crisis – all of these events were imbued with what educators today like to call "teachable moments," and my parents seldom missed an opportunity to seize upon them. 

Art of conversation
But like most American families then, dinnertime was reserved for two things: food, and conversation. 

If the former was lacking it was because Mom, when she went back to work full-time, made the regrettable decision to champion something called "creamed corn" – a canned concoction bearing an uncanny likeness in texture (and, presumably, taste) to cat vomit. 

If the latter was lacking, well, that was a bigger problem. You were expected to take part in the conversation. No televisions or radios violated the fiercely guarded airspace of our dining room.         

Science backs tradition. There have been numerous research studies supporting the notion that a shared, family dinner experience has widespread benefits.

A University of Michigan study of children ages three through 12 found that eating together as a family was the strongest predictor for fewer behavioral problems.

But what constitutes "eating together" these days? 

Lost in the glow
Driven from our favorite pizzeria by a blaring, flat-screen television, I recently met up with my wife and kids at another pizzeria just down the road. My daughter Alexa, who otherwise has the attention span of a gnat, was rapt as she watched the lone television (at least with no audio) in a far-off corner of the restaurant.  I repositioned her at the table, and managed to steer her back into the conversation. 

Not five minutes later, a father sat down at a table next to us with his three children. Before they could even get their coats off, two of children had fallen under the hypnotic gaze of the television, the third to a portable video game device. The entirety of their dinner conversation consisted of a mumbled dinner order, and Dad calling for the check.   

If the art of conversation has not been lost, it's eligible for the most endangered-species list.

Television sets in restaurants are emblematic of a pervasive social aloofness aided and abetted by video games, cell phone, blackberries and, yes, television. If people never develop the social skills necessary to carry a conversation, why would they want to use them when they go out to dinner? 

I suppose it's easier to fill the voids in a conversation with a client, a date or even a spouse if you've got television as a distraction. But do we really need to see the latest contestants from "The Biggest Loser" stuffed into their Lycra while we try and pair a nice white wine with our chicken francese?   

Drawing a line
Frank Stocco, owner of National Restaurant Design based in Minneapolis, estimates that 95 percent of the start-up restaurants he has helped design are making use of flat-screen televisions, but draws a distinction as to how they should be used.

"What is important in a dining setting is a full sensory experience, and overkill with any one aspect of it can destroy the whole thing." Stocco cites an Italian restaurant that uses LCD screens to display works of art from Italy, with classical music as a backdrop – a setting he says can actually stimulate conversation. 

When it comes to commercial television in eating establishments, he says, "I think you have to draw the line."  That line may soon be re-drawn. Some restaurants have begun to use table-top systems that allow you not only to view the menu and pay the bill, but also to access a touch-screen TV monitor, the internet, and video games.           

In 1986, the Swanson TV dinner was inducted into the Smithsonian Institute. Here's hoping today's restaurateurs give this nerve-grating trend the same treatment, and mothball it.  

LONE GROVE, Okla. – It's the insulation in the trees that directs you where to go when you cover a tornado.

More than the twisted siding, or trees down, or flashing emergency lights after dark – tornados always, and I mean always, leave the pink insulation found in your attic and inside the walls of your house everywhere. You'll see it plastered to the smallest twigs on trees, flapping in the wind on the points of barbed wire, and hidden in places only to resurface weeks or months later.

VIDEO: Okla. residents return to destruction

There's a lot of insulation in the trees here in Lone Grove, Okla. A tornado with winds estimated at 170 mph ripped through Lone Grove just after dark Tuesday night – destroying dozens of homes in its path and leaving at least nine dead.

The neat little trailer park that is allowing us to broadcast used to have a lot of huge oak trees. Those that are standing now look like they have pink leaves because of all the insulation. I've gone back to places hit by tornados a year after the fact, and seen insulation still clinging to branches.

The clean-up is starting in earnest here now, people picking through piles that used to be their homes – coming up with teapots, miraculously unbroken china, and all sorts of things.

VIDEO: Deadly twister slams Okla. town

A woman across the road from us has been loading up the bed of her pickup truck with bags of her family's clothing for the better part of two hours. She says once it is all washed a couple of times, it should be fine. But right now it's all covered with tiny bits of pink insulation.