Of course, that is not the only kind of detector. I remember at
the top end of the street I lived on where it T-intersected with another
larger street, there was a demand light using an ultrasonic detector on
a pole. There were two cars waiting in the right lane and we pulled up
in the left (center) lane. We sat there for too long, and I then got
out of the car, walked up closer to the pole, and moved a large (Man
Sized) box of Kleenex flat-bottom rapidly towards the ultrasonic
detector. I then got back in the car just in time for my father to pull
away as the light changed. (The problem was that nothing was moving
close enough to it for it to detect. I made up for the lack of surface
area of the Kleenex box with speed of motion. :-)
Email: < firstname.lastname@example.org> | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
Advanced left turn arrows around here are activated by a detection
loop under the third car back. I often sit on the loop in order to get
the advance arrow to make the turn into the subdivision. I often get
strange looks from drivers in the number two lane on my right. One day
I looked in my mirror to see the driver of the police car behind me
laughing his ass off - he knew exactly what was going on.
Gerry, did you start carrying a sign around with you in case another
cop pulls up behind you? "Loan me your strobe unit. This light takes
Never tell people how to do things. Tell them what
to do and they will surprise you with their ingenuity.
-- George S. Patton
They started to use those in NYC but the traffic engineer there told
me they didn't work out well at all. Although they were mounted on
cross arms high above the traffic, after someone discovered that
they made great tweeters they'd get stolen within days of
Those darn detectors were a pain in the butt when I was riding my
motorcycle during the wee hours. Usually had to wait for a car to
pull in behind me. Tried moving my cycle so it was setting right over
the wire, but it usually didn't help any.
Always found it somewhat amusing to see someone waiting at a demand
light, but not pulled up far enough to be in the detection zone :)
What the heck do you drive that has problems getting detected?
The general wisdom around here is that if you stop
at a light while on a street legal motorcycle and the
light doesn't change after a prudent interval, the
light is defective. Proceed through the light with
Back at the time it would have been easy enough to ask, just never
thought of it when we happened to have a vehicle with officer
in for service work. What you're saying makes plenty of sense, but
police officers don't always respond sensibly.
Used to happen in my area along a busy street with a left-turn arrows.
You wouldn't get an arrow if didn't sense a vehicle waiting for one.
Most often my wait was short, busy street and something large would
pull in behind me. I would just pull up farther to be sure the vehicle
behind me was setting in the zone. There was a time or two though where
there didn't seem to be anyone else wanting to go my direction...
Guess I need a bigger motorcycle. Maybe one of those Bombardier
Spyders. Of course then I would need a bigger garage ;-)
The detector works, previously the light had been changing as soon as
I drove up and then suddenly it didn't, but then it changed when I
inched forward. After a few days I saw it turn red as I approached,
started counting seconds and found the answer. I figured that if there
was a retriggering holdoff it would be some round number and sure
enough the light changed after 30 seconds.
This was ~15 years ago. I'm rarely out in the wee hours anymore. Pretty
much all of the lights using the buried-in-pavement-wire sensor did
this though. I don't recall any of them detecting my motorcycle no
matter where I was setting over them. This particular street has a lot
of them too.
They don't give one whit about motorcyclists around here. If they did
they wouldn't be installing the bastard median barrier cables up and
down all our expressways...
It might be interesting to make a loop of heavy copper wire that
encloses your bike. It would have to be out of the way and
unobstrusive to be acceptable, but you might be able to contrive that.
It should be an electrically closed loop with maximum possible area.
See if that increases the bike's "visibility" to inductive loop
I like how you think Don, always have :)
A true engineer trying to solve the problem. I tried a few different
positions for where my bike was setting, but that is about all you can
reasonably do and keep an eye on traffic too. You can't do much to the
motorcycle either without messing with your ground clearance and/or
maneuverability. It would be fun to play with, if I could find a traffic
engineer that was interested in messing with it. But those days are
long gone I'm afraid... They might have even addressed the problem by
know. As I said, this was awhile ago and I haven't been in a position
to test them for many years now.
Do appreciate hearing though that I wasn't missing something simple
that would have solved the problem :)
When I was 15 we went duck hunting from an old wooden rowboat on a beaver
pond here in Northern Minnesota on a brisk 35 degree day. a couple of
mallards flew from left to right and I shot one. Another duck flew by the
opposite way and while trying to shoot the duck, my brand new Mossberg 500
flew out of my hands and into the drink. There it was, cocked with the
safety off in five and a half feet of cooooold water. I jumped overboard
after stripping my work boots off and gingerly felt around with my stocking
feet for my prized shotgun. I was able to raise it from the loon shit on the
bottom and we hightailed it for home.
Don, your knife should be a piece of cake to rescue.
You know how water diffracts the image of an object under it's surface,
right? Well it also tends to shift the location of an object that sank
right below you to a location that can't be guessed, and is usually many
orders of distance further then you thought, specially cold water...
CAN be guessed. If you're looking straight down, it's straight down. If
you're looking at it on an angle, it's closer to you than it appears.
How much depends upon the angle and how deep the water is.
(Bow fishing 101).
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