Frequency Band Comparison

[MNRotrMedic]

Very basic question for you all. As i've been looking aroung the RR Database i've been noticing a 'theme' to the use of the radio bands. ie 400mhz & 800mhz in major cities 150mhz & VHF Lo in more rural areas. What is it about these bands that makes them more prevalent in certain areas and not in others?

In my area for instance, almost all public safety comms are on VHF (155.625, 155.775, 154.4, 155.295 etc.) except for the "metro" who are on an 800mhz TRS. There is talk about moving all local stuff to the new statewide APCO25 TRS but that's slow in coming. Thanks

 

[PhilJSmith67]

Overcrowding is the reason that so many agencies in populated areas have fled for UHF and 800 MHz. Cost is another issue; smaller rural towns typically don't have the funds to upgrade to more expensive equipment.

 

[nd5y]

Another reason is that for a long time the FCC did not allow trunking below
800 MHz.

Even though VHF low band works really well when using mobile radios and
has much greater range than 800 or 900 MHz using the same power and
antenna height, lots of systems moved out of VHF low band because of greater interference from skip and noise from electronic devices, poor
building penetration and very poor hand held performance because of
antenna size at those frequencies.

 

[MNRotrMedic]

Another reason is that for a long time the FCC did not allow trunking below
800 MHz.

Even though VHF low band works really well when using mobile radios and
has much greater range than 800 or 900 MHz using the same power and
antenna height, lots of systems moved out of VHF low band because of greater interference from skip and noise from electronic devices, poor
building penetration and very poor hand held performance because of
antenna size at those frequencies.

Thanks nd5y, that's what i was asking about. Stuff like interference, use in buildings, etc.