Thanks for sharing that, Martin. Its a great story.

--Bob

Martin McCormick wrote:
> I first learned to use the white cane in the late sixties
> and we were taught to listen to the traffic flow which was a
> common practice back then.  The signals were a lot simpler
> without as many turning arrows so it was usually no problem to
> know when it was safe to go for it.  In the eighties, I lived in
> a direction from work that required crossing a couple of streets
> that had lights.  They did have pedestrian buttons, but no
> beepers.  Contrary to what you might think, busy streets are
> actually safer than intermittently-used streets because you get a
> constant traffic sound.  These streets were moderately busy, but
> there are still long pauses in which nobody is coming from
> anywhere.
>
> 	You go up, push the button, and probably set a bit on a
> controller which is honored the next cycle of red for cars so
> there is no way to guess when the signal actually changed.  There
> are also inductive loops in the pavement which give cars the
> chance to influence the flow and motorcycles fits when they don't
> have enough iron to trigger the sensor.:-)
>
> 	After getting the hell scared out of me a couple of times
> when there wasn't anybody around to hear, pushing the button, and
> still managing to jay-walk, I called up our mayor at the time and
> asked about the chances of getting some of those beepers right
> here in relatively small Stillwater, Oklahoma.
>
> 	As luck would have it, the mayor was a little more
> visionary than some folks in similar positions and thought it was
> a great idea and, one of the Electrical Engineering classes at
> Oklahoma State University was in need of a project.
>
> 	This was all back in 1983 so some of the details are a
> bit fuzzy, now, but I recall, it was a record short time like
> maybe a few weeks before there was a nice chirping bird sound for
> North/South traffic and a video game warbling sound from one of
> those Radio Shack noise maker chips for East/West streets.
>
> 	Ten years later, we moved to the other side of the campus
> and I didn't have to use the audible signals any more for years.
>
> 	Fast forward to 2006.  There has been lots of new
> construction on the campus and the way I normally get to work was
> blocked for a while so I had to go a different direction and
> begin using the audible signals once more.
>
> 	The first day I used them, something was dreadfully
> wrong.  The chirping bird was still there and the video game
> sound effect was now a cuckoo which is no big deal as long as the
> sounds are different.  What was wrong was that in the
> intervening years, somebody in their infinite wisdom reversed
> the sound so that the chirping bird was now East/West and the
> cuckoo is North/South.  Fortunately, the one time I got it wrong,
> nobody was coming, but I was sure confused when the sound was
> 180-degrees out of phase with what the traffic was doing.  The
> sounders and it appears, the whole system had been replaced
> somewhere along the way and, I guess, there is no standard so the
> moral of the story is to know what is normal for this
> intersection.
>
> 	They've got those pedestrian beepers all around the
> campus, now, and I always feel a little glad that I started the
> ball rolling in 1983.
>
> 	I think the original beepers were wired to the 120-volt
> power to the Walk light and the very first ones succumbed to a
> lightning strike.  Some of the modern ones adjust their volume to
> get louder when there is a lot of ambient noise so that they
> don't drive permanent residents crazy by beeping loudly at 3
> o'clock in the morning.
>
> 	The inductive loops I mentioned used to thoroughly jam AM
> car radio reception and you could hear the carrier swish across
> when the car de-tuned the loop.
>
> Martin McCormick WB5AGZ  Stillwater, OK 
> Systems Engineer
> OSU Information Technology Department Network Operations Group
>   

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