Bring on the Replacements

You can model the San Francisco Bay area with your right hand. Bring the tip of your thumb and index finger together, then part them slightly. The gap between them is the Golden Gate, with its famous bridge. Going clockwise from there, the end of your bent index finger is Marin County. Berkeley and Oakland are at the base of your index finger. San Jose is at the base of your thumb. The rest of your thumb is the Peninsula. San Francisco is the whole tip of your thumb. Going back south, The knuckle below your thumb's nail is San Bruno Mountain. That's where our story starts.

San Bruno Mountain is the first home of San Francisco's FM and TV stations. About half of the former and most of the latter have moved to Sutro Tower in the midst of The City -- a landmark locals call "the world's largest roach clip." One of the few remaining TV transmitters on San Bruno is KTSF, which calls itself Channel 26. That was its old analog channel. Now digital, it actually radiates on Channel 27, even if TV tuners still say "26". In fact the displayed channels for most TV stations in the US are now other than those they transmit on. Being digital, they can transmit data that tells the recieiver what channel to display, regardless of the actual channel used. But that stuff hardly matters, because the percentage of Americans still watching over-the-air TV is down to single digits. Instead they watch watch cable or satellite. Or they bypass TV altogether and watch on a computer or a hand-held mobile device. Still, TV stations are required by the FCC to put out a signal, and KSTF's is listed at half a million watts.

Inside the base of KTSF's tower is a small yellow shack with a leaky roof. It was here that I stood with Tim Pozar last May as he showed me how gear in a rack inside the shack that was relaying many megabits worth of Internet bandwidth from one point to another, using powers measured in thousanths of a single watt. He and a colleague were busy shaking down a link to the Maker Faire that would happen down on the Peninsula a few days later. (It worked fine.)

Tim's resume encapsulates the convergence between analog and digital, and broadcast

is very little "broadcast engineering" now. Most of the time
is doing IT. Fiber, twisted pair, Ethernet, IP, switches, routers,
Linux servers are the new technology for distribution of broadcast.
Analog is no where to be found now.

What we had here was a perfect example of re-provisioning at work. It's an old-hat subject for

I've always known Tim Pozar as a guy with at least two hats. (Not that he actually wears any — his ample hair does a good enough job.) One hat is broadcast engineering. I think that's how I met Tim