CHP going digital on low band??

nd5y

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I don't know how accurate any of this is.

JVCKENWOOD Corporation (JVCKENWOOD) and EF Johnson Technologies, Inc. (EFJT), its communication systems subsidiary in the U.S., have been awarded a contract from the California Highway Patrol (CHP) in the U.S. to deliver professional digital radio systems.
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The contract is for the supply of professional digital radio systems for installation in approximately 3,300 vehicles owned by the CHP.
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In addition, these digital radio systems can provide radio communication across extensive areas by also using low band radio frequencies (50MHz), which are good for long-distance communications. Different counties in the State of California operate digital radio systems that use different band frequencies and different protocols. Given the circumstances, we were awarded a contract to develop and supply solutions capable of operating four digital radio systems to be installed in each vehicle using one controller unit.
 

ko6jw_2

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They already use 700Mhz P25 radios for extenders. If they are going to change the low band system to digital it will be a long term project. I see it as having mixed results.
 

milf

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I forsee a transition away from low band over the next few years. Watch for new licenses in VHF High, UHF, 700/800, in addition to already in place UHF and 700 MHz P25 repeaters.
 

norcalscan

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Huh? This is just a sales press release saying JVCKenwood sold CHP an RF stack which will (obviously) be P25 capable, from lowband on up through VHF, UHF and 700, along with the EFJ handhelds. It doesn't say a thing about actually switching to P25 on lowband...am I missing something?
 

mmckenna

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It doesn't say a thing about actually switching to P25 on lowband...am I missing something?
No, you didn't miss anything.
The NX-5600H low band radio won't do P25, only NXDN and analog. CHP isn't going digital on low band.
And it would be impossible to get the coverage they have now by switching to VHF high, UHF or 700/800MHz statewide.

Kenwood is selling CHP the RF decks to replace the mix of mobile radios they have now. Yes, the radios have digital capability, but they'll be using analog low band for a long time to come.
 

K6CDO

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The basic 700/800 radio in the CHP fleet is a EFJ 5300, which is P25 Phase 1 only (and at end of life). This will replace those radios.
As noted in the Release, the other bands (above 50 MHz) will be covered by multi-mode VHF and UHF radios. This will allow CHP to interoperate with more local agencies, including many who have gone digital without using P25.
 

norcalscan

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This will allow CHP to interoperate with more local agencies, including many who have gone digital without using P25.
Just want to say a few months ago TGU had a moment of multiple accidents at once in the Unit, along with a big rig rollover on I5 shutting it down temporarily. In the confusion of multiple responses and expedited demands for CHP, I heard a digital voice on local net, "Red Bluff, CHP 3651, we will have a unit enroute to your call in the south county here shortly, still tied up on this call at Snively." Talk about head snapping 180 and jaw dropping, someone in our CHP office actually knows the power they have in their HT! :geek: First time hearing CHP up here actually change a knob on their HT. Small steps!

I won't go into the temporary confusion I had driving around and close call hits on a 770Mhz freq and it's TGU local, and then local PD and local Sheriff being rebroadcasted. Few minutes later realized Fish and Game unit had his truck scanning over his extender.
 

gmclam

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I heard a digital voice on local net, "Red Bluff, CHP 3651, we will have a unit enroute to your call in the south county here shortly, still tied up on this call at Snively."
Are you saying that CHP was broadcasting P25 on an otherwise analog channel (Red Bluff local net)? That's confusing as I wonder who is normally able to receive P25, except many of us scanner operators.
 

norcalscan

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Are you saying that CHP was broadcasting P25 on an otherwise analog channel (Red Bluff local net)?
Sorry - as I typed that I realized it might be confusing. Transmission was proper analog, but the voice was definitely going through a digital vocoder, like you can tell when listening to CHP and the officer is on his HT talking through his extender.
 

scannerboy02

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I'm glad to see this radio project is moving forward a bit quicker than I would have expected. The state already has 700MHz P25 trunking sites on the air in the Sacramento area.

With the number of P25 trunking systems on the air throughout the state, if they could get everyone on board (this could be the biggest hurdle) with linking those systems together via a 'state owned' controller (a system of systems) they would have rather good statewide coverage almost immediately. They would still need fill-in coverage from place to place, but for the most part a good amount of the state has coverage right now.
 

K6CDO

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RF Technology modified one of their P25 repeaters to support low band. They've done data on low band using the P25 CAI between repeaters.
Considering the RF noise environment at Low Band in many areas, I suspect the CHP would not want to endure the impact of any noise / noise floor interference to a P25 signal at Low Band, especially during a critical incident.
 
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Considering the RF noise environment at Low Band in many areas, I suspect the CHP would not want to endure the impact of any noise / noise floor interference to a P25 signal at Low Band, especially during a critical incident.
Likely why we haven't seen a P25 low band terminal.
 

russbrill

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No, you didn't miss anything.
The NX-5600H low band radio won't do P25, only NXDN and analog. CHP isn't going digital on low band.
And it would be impossible to get the coverage they have now by switching to VHF high, UHF or 700/800MHz statewide.

Kenwood is selling CHP the RF decks to replace the mix of mobile radios they have now. Yes, the radios have digital capability, but they'll be using analog low band for a long time to come.
Last I heard CHP was pretty committed to the Low Band (Base to Mobile, Mobile to Base)… Coverage is their major concern...
 

mmckenna

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Last I heard CHP was pretty committed to the Low Band (Base to Mobile, Mobile to Base)… Coverage is their major concern...
Yeah, I think most people that live outside California don't understand the terrain challenges or the sheer size of the state. CHP would have a really hard time moving away from low band and still having reliable coverage.
 

nd5y

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Considering the RF noise environment at Low Band in many areas, I suspect the CHP would not want to endure the impact of any noise / noise floor interference to a P25 signal at Low Band, especially during a critical incident.
Since when does noise only affect digital signals?
 

kayn1n32008

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Yeah, I think most people that live outside California don't understand the terrain challenges or the sheer size of the state. CHP would have a really hard time moving away from low band and still having reliable coverage.
California is not that big and terrain challenges are not impossible to overcome. VHF-hi would be a logical choice. It just depends if CHP wants to throw enough money at the problem to do it right or not.

BC(2.23 times larger area) has 4 separate VHF-Hi repeater systems that cover the vast majority of the province.

Probably 1000+ repeaters, designed for each users coverage needs.
 

milf

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Plus each center has a P25 uhf and 700 repeater in place. Not just those extenders. And this is also about interop Dawn to dusk abilities for all the MCU they run. Both the SUVs and that big RV
 

mmckenna

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California is not that big and terrain challenges are not impossible to overcome. VHF-hi would be a logical choice. It just depends if CHP wants to throw enough money at the problem to do it right or not.

BC(2.23 times larger area) has 4 separate VHF-Hi repeater systems that cover the vast majority of the province.

Probably 1000+ repeaters, designed for each users coverage needs.
Yeah, compared to most provinces, California is small. You got me there.

California has some "Statewide" VHF networks, but they don't cover the whole state. Just too many deep valleys for it to work well enough. Add in there are too many silos that agencies don't want to share systems. Maybe some day that'll change, but I don't see it happening any time soon. CalFire has their system. Department of Fish and Game has their system, etc…..

VHF Low band works.

And then getting enough clear VHF pairs would be difficult. I'm trying to get a few pairs for a system upgrade, and it's difficult. Not impossible, but a lot of the pairs we are finding are very close to existing systems where we'll have to share sites.

Budget is an issue, too. That's a lot of money for new sites, new repeaters, etc. Would take a lot of years to roll out a system that big. Simply replacing the existing CHP radios is being spread out over 3 years. Building a new statewide multi-channel VHF High network would take a very long time.
 
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