Wednesday, September 28, 2005

I'd Been Wondering About That

Pittsburgh has roughly 6 major arteries coming into the city. Half of those make the last phase of the trip coming through the hillside, through the Fort Pitt, Liberty, and Squirrel Hill tubes. When there's no traffic this part of the trip takes a minute or two. During rush, it can be longer. A year or so ago, when they were working on the Fort Pitt tunnel, people were in there so long that they installed air monitors to insure people weren't getting too much carbon monoxide (too much, as if it is possible to get too little CO).

Because of physics, when you drive through a tunnel you lose radio reception. For AM this is true even when driving under a bridge - hence the Steve Wright joke about his friend the AM radio announcer who you couldn't hear speaking under a bridge.

It always seemed to me like it would be a good idea for one of the Pittsburgh radio stations to take a hunk of their advertising budget and use it to technically defeat the reception problem in the tubes. Then they could have a real cool campaign:

WDVE- The only station to rock you
ALL THE WAY
to work!!!


I imagine that even if they didn't get a lot of full time converts that just about everyone listening to the radio would flip for the time they were in the tunnel. Anyway seemed like an interesting thought.

And apparently not such an original one.

Recently, much to my surprise I drove through the tunnel and the radio didn't cut out. I did a full double take and for a moment wondered if I was actually listening to a CD rather than the radio. But there it was, radio signal, in the tunnel. What was up with that?

It turns out that an intrepid CMU Professor and a gang of graduate students had the same kind of thoughts and as a class project had designed and installed FM antenna systems in the Fort Pitt and Squirrel Hill Tunnels. There's an article about it in this weeks Pittsburgh City Paper (although it isn't posted online yet - its in a section called "You Had to Ask"). The article lists a site: http://www.tunnelradio.net/ where you can read about the project from the participants.

So I guess the world isn't so screwed up that no good things happen just for the sake of good things happening. Or maybe this is the exception that proves the rule. For whatever reason, I'm glad I don't have that annoying gap in my Morning Edition anymore.

Very cool.

3 comments:

Anonymous said...

I drive through the Caldecott Tunnel daily these days here in SF -- it's about 3/4 of a mile long, with curves.

The FM radio reception is spotty in one tunnel (you can see the broken loop wires on the ceiling), but the other two work pretty well.

This seems to be the trend in tunnel remodeling-- when they're remodeled they install these systems. I think it's also possible to get cell phone service on the same wires, although the higher frequency may not transmit on the long wires as well. It may simply be the companies have started installing cell towers inside the tunnels.

Anonymous said...

Thanks for spreading the word. I work on the project and we're all really happy to hear people are enjoying the service.

Ironically, those of us working on it don't drive through the tunnels (Fort Pitt and Squirrel Hill) very often, so if you've noticed a problem feel, free to drop us a line at tunnelradio@vt.edu. If you can, tell us the radio station you're listening to and perhaps what sort of antenna your car has. Lots of cars are putting their FM antennas in back side windows or read wind shields these days so it's tricky to know how everyone's car will work with the signal.

Anonymous said...

Here in Washington DC, they've spent untold amounts of taxpayer money to install cell phone repeaters in the Metro subway tunnels so people can chat on their way to work (because it's unconscionable for people to not be able to yak away on those things for even two minutes at a time).

Well, ever since the London bombings, that system has been suspended out of fear that terrorists could remote detonate bombs with cell phones in the subway. It's unclear if the system will ever be activated again.

Another several million dollars in tax money flushed down the virtual toilet. Kinda gives you a warm fuzzy feeling inside, huh?