CHP Blu / Blu1/Blu2/ Blu W/ Blu East

[scottyhetzel]

Has anyone figured out why the CHP needs this many blues for each division ? I never here the blue or the new additional blues in the desert. I use to hear the main blue 42.340 for years in the Southern division areas. Usually for major sig alerts or pursuits. I understand lately the divisions are using the blues for cut overs. Anyone have any viable ideas... I sure there is someone in the know.

 

[K6CDO]

The BLUE channel was the statewide secondary channel in the days CHP used 4 frequency crystal controlled radios (pre-1980s). As technology has progressed, along with growth in population (statewide and within the CHP), the need for additional tactical channels has increased.

As CHP has expanded their radio operations, they (along with the rest of agencies operating in the VHF and UHF bands) have been working to balance their need for additional channels along side their and other existing agency's operations in the same remote radio sites.

For example, CHP may want to install a new primary or tactical channel to cover a given area of the state. They rent vault space from the local county. If that county also uses VHF-low band in that site, the channels selected may not work. So CHP comes up with another channel pair to use, which will work in all of the radio sites used to cover that given area.

It is the same for anyone developing the infrastructure to support radio operations. The problem of onsite interference is compounded in the two VHF bands, as those frequencies are not paired by the FCC the way the UHF / 700 / 800 MHz bands are.

 

[carlt]

I don't know for sure why, but if one looks at the 2009 "new frequency" list, every division will still have the original Blue - 42.34, Blue1 - 39.14, AND a separate Blue2. Since the signal still travels, there should be interference between Border & Inland (for example) if both need to use Blue or Blue1 at the same time, for whatever reason. So the Blue & Blue1 would be for statewide interop and Blue2 for local use? Just guessing until we see how the system finally gets finished!

 

[scottyhetzel]

I don't know for sure why, but if one looks at the 2009 "new frequency" list, every division will still have the original Blue - 42.34, Blue1 - 39.14, AND a separate Blue2. Since the signal still travels, there should be interference between Border & Inland (for example) if both need to use Blue or Blue1 at the same time, for whatever reason. So the Blue & Blue1 would be for statewide interop and Blue2 for local use? Just guessing until we see how the system finally gets finished!

Thanks for your help carlt. It makes sense. I never heard conflicts on blu 42.340 when i lived in pasadena. In fact i rarely heard the blue. Looking forward to the finished product too.