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神经网络昆斯林的新闻组分类2006

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From: [e-mail] (Ken Buck)
Newsgroups: rec.autos
Subject: Re: Do trains have radar?
Message-ID: <buck.734786597@granite>
Date: 14 Apr 93 11:23:17 GMT
References: <[e-mail]>
Sender: [e-mail] (Network News)
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[e-mail] (T.M.Haddock) writes:
> I came upon a 
> train parked on a trestle with its locomotive sitting directly over
> the northbound lanes. [...] Just as I passed from underneath the trestle,
> my radar detector went into full alert - all lights lit and all chirps,
> beeps, and buzzes going strong.
> Could this have been caused by the train's radio or what?

recently-manufactured locomotives have wheel-slip detection systems
that use frequencies shared with police radar (i forget which band).
these will set off your radar detector if you get close enough, though
i believe the range is pretty short.

BTW, railroad police sometimes use radar to check for speeding trains
(just like regular police check for speeding cars), although the
intent here is for safety, not revenue collection (unlike with cars).