This article is from the Motorsport FAQ, by A H Henry bspahh@midge.bath.ac.uk with numerous contributions by others.
You can get a battery operated hand held scanner, a bigger "base"
scanner which is powered from an AC outlet, or a mobile scanner which
connects to your auto's electrical system. You will want a hand held
scanner for spectating at a race.
Radio Shack, Uniden (Bearcat and Regency brands), and Cobra offer a
wide choice of scanners. Personally, I [ Bob Parnass ] don't recommend
AOR brand scanners.
20.4.1 Uniden
The Uniden Bearcat 200XLT (aka the 205XLT) is by far the most popular
scanner among race fans. This US $ 200 to US $ 250 model differs from
Radio Shack's similarly priced model in that it has a wider frequency
range, and the ability to store more programmed frequencies in memory.
It stores 200 frequencies and can receive the 800MHz band. They also
have a new model out, the Sportcat, which has a bright yellow case like
the "sports" walkman.
20.4.2 Radio Shack
The US $ 200 model from Radio Shack only stores 100 frequencies, and
can't receive the 800Mhz waveband. The Radio Shack Pro-43 is fairly new
and is the model at the top of the range. It is less susceptible to
interference than the Uniden BC 200XLT.
With a portable aviation intercom and some headsets you connect up
the Pro 43 and allow conversations with in addition to hearing the
scanner.
 
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