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  • #16
    Originally posted by LVFD301 View Post
    Anything just requiring the emission mask change, ie, wideband to narrow, does not require a coordinator. Any frequency change however, does, and yes should have been started a while ago.

    Luckily 90 percent of people will only need the emission change.
    Correct: Our license change had to go through the freq.co-ordinator as we were moving our primary transmitter site to a newly installed tower, Going from a 80' tower on one island to a new 300 ft tower 4 miles north on another island.

    We've always had some overlap with distant departments due to the radio waves traveling over the water. Some departments 100 miles away hear our traffic better than our dispatch center.

    When the weathers right in the springtime we get Orange NJ skipping in across the atlantic better than we can hear our dispatch center 40 miles away.
    Hopefully our new voted receiver sites with a microwave back haul will eliminate some of these problems for us. Certainly has improved the effects of storm interference.
    Our weakest problem has been the county system that was a low bid project which has had some issues.

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    • #17
      [QUOTE=tree68;1255641l.

      A bright spot - since we're on the border, there could be Homeland Security dollars available for a consortium of the counties along the border.[/QUOTE]

      Tree : we were able to get some funding for our project from homeland security as we have the shipping lanes for a major port facility just offshore. We work with port security group on occasion and they funded some of the new equipment through a grant. The coast guard does their inbound vessel inspections as they pass by our islands and wanted the ability to use our com systems infrastructure if needed.

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      • #18
        Originally posted by tree68 View Post
        Figuring an average of 10 mobile and 10 handheld radios per fire department, that's upwards of $60-70,000 per department for new radios. While we've implemented VHF-High paging, some departments are still using the low band frequency (they are simulcast).
        Are you going to keep the VHF frequency for paging only? Are you using analog or digital POCSAG/Flex?

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        • #19
          Originally posted by koechler View Post
          Are you going to keep the VHF frequency for paging only? Are you using analog or digital POCSAG/Flex?
          There's a lot of "what if" still floating around that - it'll depend on which way we end up going, ie, trunked or VHF-High repeated.

          Our paging is currently analog, two-tone sequential for the most part. The only digital is the secondary notification via cell phone texts. Given that most everyone who uses the texting (direct from dispatch is only the chiefs, but we use Google and Yahoo groups, among others, to spread the info to any member who wants it), changing over to a pure text notification might be better received than it would have been a few years ago. A lot of people like to be able to monitor what's going on with their neighbors (and the rest of the county).

          Island - We have the St Lawrence Seaway for a "neighbor." I'm sure we have many of the same venues you have for funding. We are currently working on/with a multi-county consortium so we can work the issues (and solutions) together.
          Opinions my own. Standard disclaimers apply.

          Everyone goes home. Safety begins with you.

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          • #20
            i personally hate narrow band doesnt work for crap in my area we are lucky if we can hear anyone else that is responding due to interference from mountians and what not in our area
            We walk where the devil dances... FIR NA TINE

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            • #21
              Originally posted by sapper937 View Post
              i personally hate narrow band doesnt work for crap in my area we are lucky if we can hear anyone else that is responding due to interference from mountians and what not in our area
              I hate that you have a poorly designed system. That must suck.

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              • #22
                Originally posted by LVFD301 View Post
                I hate that you have a poorly designed system. That must suck.
                +1

                At least we know why our system used to suck worse than it does today - when it was implemented there were no pagers or hand-helds. It was intended to set off firehouse sirens and talk to fire trucks.
                Opinions my own. Standard disclaimers apply.

                Everyone goes home. Safety begins with you.

                Comment


                • #23
                  Originally posted by sapper937 View Post
                  i personally hate narrow band doesnt work for crap in my area we are lucky if we can hear anyone else that is responding due to interference from mountians and what not in our area
                  My guess would be that your wide band system used previously was marginal at best and switching to narrow band with out a propagation study being done is why you are experiencing issues.
                  System design for any radio network is a very important part of the program. You can't just take the word of a salesman that it will work fine. You need an engineer to design the right equipment to make it work without problems when you get into mountainous terrain .

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                  • #24
                    Aren't you guys worried about switching to P25 with all the bad press out there? I just read the article on the front page of this blog and it gives me the shivers.

                    http://blog.tcomeng.com/

                    Don't you also somehow loose the ability to have an open channel in a digital trunked system? I was told that the switch will just break down if it has to connect to too many digital terminals at once.

                    The same will happen if you use a talk group for a fire incident and tons of people switch to this talkgroup just to listen in.

                    Are people just bad-mouthing P25 for no good reason or is there something behind this bad press that should make us reconsider paying all this money?

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                    • #25
                      Good article , but mostly a rehash of what several of us here have been preaching for a couple years.

                      Don't get sucked into buying a half designed system based on your budget or the promises of a radio salesman.
                      Do not allow some town/city/ county administrator to make purchasing decisions when it comes to public safety communications systems.

                      Digital APCO p-25 systems are inherently complicated by design and making them work properly is not an easy or inexpensive task.
                      there are many examples of regional systems that were installed with the promises of perfection. When it came to testing them , it was found that they had less than 50% coverage or that it just couldn't be made to work without doubling or tripling the amount of infrastructure.

                      a contract that starts at $$$$ goes to $$$$$$$$$$$$$$$ when trying to retrofit a patch or redesign after the fact to make something work the way that the salesman promised the administrator.


                      Tower sites and required land acquisition cost can get very expensive, Leasing space on commercial towers is an ongoing expense that most systems can't afford, and they are not available in a large part of rural areas.

                      Far too many people are losing sight of the KISS principle. Keep the equipment simple and firefighter proof, make it so it will work anywhere , anytime without relying on high technology to make it work.

                      The best example of this I can think of is two radio grant apps from 2007 AFG that I worked on.
                      Both had the same number of mobile & portable radios. same coverage areas, similar terrain.

                      System #1 was based on an analog VHF narrowband system.

                      #2 was based on an 800 mhz trunked system where they had to purchase from one vendor
                      due to a proprietary system design

                      System #1 was completed and successful for the cost of $60,000 with a 99% area coverage and done keeping the KISS principle in mind.. I say 99% coverage because there is no such thing as a perfect system.
                      Not too many folks really need or can use a full trunked multi bank system.
                      Most cannot afford it.

                      System #2 was completed for an initial cost of $172.000 with an additional expenditure after installation of $56k to install interior receiver antennas in many office buildings and big box stores so they could actually use and communicate on the new equipment. This is not including the cost of the existing infrastructure which had been previously installed & paid for.

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                      • #26
                        Daryl's blog has some good information, but some of what he posts is biased and extreme.

                        P25 has its place. A well designed P25 system can rock. (NEVER, i said NEVER use digital or repeated fireground channels though)

                        A poorly designed analog system sucks. A poorly designed P25 system can suck.

                        P25 will help to recover some coverage issues due to narrowbanding.

                        Comment


                        • #27
                          Having implemented a military installation digital P25 system, all of the comments are right on.

                          Because it's theoretically possible to lose the entire system, I started from day one with several simplex channels, which were programmed into all radios. When it came time to do a full system service (one tower at a time), that planning paid off, albeit with many of the same limitations that existed on the system when they were using an analog system.

                          Once they got over the culture shock, the users have come to like the system (some deep seated distrust still exists). Outside, coverage is near 100% throughout the area covered by the system, and we've successfully tested to nearly 20 miles in all directions with handhelds.

                          Although I heard recently that the fire department wants to go back to an analog system. For some reason they can't get it into their heads that they've got a system right now with more talkgroups than they usually use, and have the simplex fireground they need for on-scene ops (there are many buildings that lose the repeaters as soon as you step in the door).

                          On top of that, their dispatcher can monitor all of the talkgroups, with the exception of the simplex fireground, and that can be dealt with as well.

                          A county near Syracuse needs something like 13 repeater sites to cover their area due to the terrain.
                          Opinions my own. Standard disclaimers apply.

                          Everyone goes home. Safety begins with you.

                          Comment


                          • #28
                            Originally posted by tree68 View Post
                            On top of that, their dispatcher can monitor all of the talkgroups, with the exception of the simplex fireground, and that can be dealt with as well.
                            Hi Tree, how do they deal with it?

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                            • #29
                              Originally posted by koechler View Post
                              Hi Tree, how do they deal with it?
                              Remote recievers microwaved back to dispatch is one way.

                              Another is not to worry about it. If I am running a scene properly there is no reason for dispatch to be listening to my fireground.

                              Comment


                              • #30
                                Originally posted by LVFD301 View Post
                                Remote recievers microwaved back to dispatch is one way.

                                Another is not to worry about it. If I am running a scene properly there is no reason for dispatch to be listening to my fireground.
                                Got ya. Thanks.

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