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Wednesday, March 7, 2012

Dialup at 4800 bps over analog cell phone as navigation aid

In the fall of 2000, I found myself sitting in the passenger seat of a car headed up to visit family in some distant part of the country. We had flown into an airport, rented a car, and then had already driven through two states to get there. Something went wrong and we got lost.

This was well before the days of in-car navigation and cell phones which could give you graphical maps. I forget exactly what complicating factor happened, like not being able to reach our relatives on the phone or them not being able to figure out where we were. Whatever it was, we were stuck. Forward progress was no longer happening.

Sure, we had set out with directions from Mapquest, but this particular town's idea of street lighting was clearly substandard. It was impossible to read their street signs at night and we probably missed a turn or two. It was late enough to where all of the stores were closed, and there were no obvious gas stations which were open, either. What now?

I found a way out of it. I had brought along my laptop and had a PC card modem which had a proprietary connector which then would plug into my cell phone. With a little luck, I could wrangle a 4800 bps long distance connection out of it back to my dialup pool at work. So now I was online with a horribly lossy terminal mode connection!

I noticed that one of the stores near us was a Radio Shack, and they had a number visible in the window, like 3210. It was obviously their street address, but what street? I decided it didn't matter, and used a yellow pages web site to pull up ALL of the Radio Shack locations in that city. Only one of them would have a street address of 3210, or so I hoped...

Eventually, that page loaded, and yes, there was a RS at 3210 on a given street in that city. So now, we actually had a starting location! It was off to Mapquest to get a new list of turns. Somehow, the resulting directions matched with what we were seeing on the ground, and we finally got to our destination a bit later.

I'd like to say this only happened once, but there was an incident in the spring of 2002 which went the same way. It involved trying to find a hotel in Voorhees, NJ, and it was resolved by noticing "hey, there's a Wendy's, and we're on X road", and that provided the "start" point for a fresh set of directions.

That time around, I actually had a GPS receiver with me, but those things used to lack detailed maps by default. You had to jump through hoops and preload them with local data before you set out on a trip by using the painfully slow serial port at 115 Kbps. If you wound up outside of the rectangles you had supplied, then forget about anything but major roads, rivers, and airports. I hadn't loaded any data for that area, so it was of no assistance.

Of course, in 2007, the iPhone landed and changed all of this craziness. Their map with the smooth scrolling and zooming sold me. Everything else was extra as far as I was concerned.

Sometimes, it seems hard to believe it hasn't even been 5 years yet.