-=> Quoting Barry Austern to Ken Peck <=-
 KP>  I've heard debates on this subject between the Dallas Bicycle 
 KP> Coordinator and engineers.  The engineers say that the detectors 
 KP> work only on ferrous materials and thus cannot detect aluminum, 
 KP> carbon fiber, or titanium.  But even on bikes with frames made of 
 KP> such materials there usually are still small amounts of steel in the 
 KP> components which _may_ be detected the detector is sensitive enough.
 BA> My Cannondale (aluminum, of course) does not activate the sensors.
My aluminum Treks sometimes does and sometimes doesn't.  I've pretty well
identified those lights on my regular routes that do and don't.
Oddly, I realize that I sometimes avoid "less travelled" streets precisely
because of problems with the traffic lights.  And I probably irritate some
motorists by waiting for the light in the right lane (but not right turn
only) so they can't make their "right on red" turn.
    ===  ==== =   _@
    Ken Peck +  _ \<._
    =========  (_)/ (_)   Kenneth_Peck@clr.com
... I wear a bike helmet because I'm too old to re-learn the alphabet.
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