DRIVERS AREN'T SLOW TO GET BILLBOARD'S SPEED MESSAGE.(CAPITAL REGION)

Byline: JULIE CARR SMYTH Staff writer

BETHLEHEM This is not a fantasy: You're driving up the New York state Thruway and a billboard flashes: ``Your speed is 72. Slow down!''

The technology is simple, and the effect is immediate.

``We've found a noticeable decrease in the speed of drivers through that section,'' said Thruway spokesman David Ardman. He said the experimental sign, located in the northbound lane just south of Selkirk, is equipped with a radar gun and a solar-powered variable message sign. It was tested for two days earlier in the month, and will now run around the clock for a week or two.

``We aren't sure what kind of …