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Old 01-14-2010, 7:20 PM
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n5ims n5ims is offline
Join Date: Jul 2004
Posts: 3,622

Originally Posted by Ablice View Post
So, help me out here real quick.

Why the public service freqs (urban) tend to congegrate around the 460MHz band?

And what about the 800MHz?

Lastly, why the highway patrols use low ~40MHz freqs?
While this may not be 100% correct, it's a close approximation and you did ask for an answer "real quick".

The public service folks quickly ran out of channels on VHF-Hi (150 MHz band) and moved to UHF quickly when it opened up to add the necessary channels.

800 MHz works better in an urban hi-rise environment than UHF or VHF. Also, the trunking systems were generally available for the 800 MHz band earlier (at least more reliable there earlier) so when they needed additional channels they moved to 800 MHz to get additional channels (although these were virtual channels from trunking).

VHF-Lo (40 MHz) has generally good coverage between mobiles and base stations over the long distances required by a state wide organization like the highway patrols and power companies. Many have gone to trunked systems now, but often keep their old VHF-Lo systems as a backup and for secondary uses.
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