Friday, June 12, 2009

Digital Rapture

It's here. The post analog era of television. The Digital Rapture. Were you left behind?

At the this writing, the panic calls to our station have been sparse. I suspect they'll trickle in as the days pass. As I put it in an inner-office memo, there's bound to be somebody out there who won't notice the analog is gone until they try to tune in Saturday Night Live. After all, we are NBC.

I'd say the majority of the issues with digital have something to do with the antenna, with the rest of calls falling into the "Can't get this f____ converter box to work" category. Most people used to aim an antenna in the general direction of the TV station and watch to their heart's content. Digital requires that the antenna be aimed with the precision of a surveyor's laser sight, and focused to a degree just slightly less demanding than that used for the Hubble telescope.

A year or so ago, some jackalopes got on TV with those "Make the Switch" spots and told people that rabbit ears would do the trick. Anybody with any working knowledge of radio and television signals knew that this was baloney. Guess what? We've turned off the analog, and the rabbit ears aren't working. That's because these guys never told you how to use them. With a few easy steps from me, you'll be watching I'm a Celebrity, Get Me Out of Here in crystal clear High Def. No need to thank me.

Rabbit ears - dipole rod antennae, to be technically and linguistically correct (One antenna, two antennae) - never really worked well even back when Jackie Gleason was on Saturday nights. They are a compromise that served only those in urban locales with strong signals that bounced off of every solid surface known to man. What's really happening here is that a reflected signal is reaching one rod of the antenna at a slightly different time than the other. When this happens the wrong way, you see ghosts in the picture. But, if you angled the ears just right, you managed to cancel out the effect of the bouncing signal, kinda like the way the IRS cancels out your yearly income. Oh, and did I mention they only work on VHF channels? UHF gets the hoop, that equally useless piece of metal little TV sets used to come with.

Like women in a singles' bar, digital receivers only want a strong signal, and have a low tolerance for weak reflected signals, so the phase cancellation method the rabbits ears use doesn't work all that well. You have to go for the direct pickup. We're still talking about TV reception, right?

First, as I said, rabbit ears only work on VHF, channels 2-13. Moving the rods around might seem to do something on UHF channels, but what's really happening is your body is changing the reception. Step away and the signal reverts to where it was. If you don't have any VHF signals in your area, you can still use your new rabbit ears as modern art, a cap holder, or for Halloween when you want to dress up as Uncle Martin from My Favorite Martian.

Second, digital television broadcast signals use what's called horizontal polarization. Easy, folks; that's not the name of a porn movie. It simply means the signal travels from the transmitter in wavy lines parallel to the ground. You know, like Lindsey Lohan returning home on on a Saturday night. That means the best antennae use horizontal rods to catch or reflect the signal, which is why an outdoor antenna looks a bit like something you could use to hang your laundry on. That means the rods of your rabbit ears have to be down in a horizontal position.

Third, this arrangement must now be rotated to present the largest aspect to the transmitting antenna. In other words, turn it until one of the rods pokes you in the eye every time you walk near it, and you'll get perfect reception - assuming you're on the second floor or higher and have a picture window looking straight out in the direction of the TV station.

And it's just that simple. So, the next time some technogeek who works in television tries to tell you rabbit ears won't work on digital, you can say, "Mine do... if you could just step a few inches to the left, and hold up your right arm."

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