Why so much conventional (no-trunking) in NYC?

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william1

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I work with a Motorola Smartzone 3.0 system which is becoming unsupportable. Since we installed it, our customer base has shrunk and cell phone carriers have expanded in our area, reducing our system's usage. Some people have pointed to New York City as an example of a busy place with many radio users doing without the benefits of trunking. What do you think of their decision to stick with conventional in so many instances? Thanks!
 

procopper7005

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I work with a Motorola Smartzone 3.0 system which is becoming unsupportable. Since we installed it, our customer base has shrunk and cell phone carriers have expanded in our area, reducing our system's usage. Some people have pointed to New York City as an example of a busy place with many radio users doing without the benefits of trunking. What do you think of their decision to stick with conventional in so many instances? Thanks!
LAPD, Dallas, Houston, etc same story. A simple system is easier to maintain and less expensive. Makes perfect sense.
 

902

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I work with a Motorola Smartzone 3.0 system which is becoming unsupportable. Since we installed it, our customer base has shrunk and cell phone carriers have expanded in our area, reducing our system's usage. Some people have pointed to New York City as an example of a busy place with many radio users doing without the benefits of trunking. What do you think of their decision to stick with conventional in so many instances? Thanks!
Trunking may not always be the most appropriate way of doing things. Many of the public safety uses in the NYC area are so high duty cycle that there is little quiescent time left to distribute among other system users. In those cases, discrete conventional channels would actually be more efficient because what would have been the control channel would be retasked for voice traffic. Many of these frequencies are localized and have busy times when they are saturated. In other words, you can't trunk when the talkgroup would be non-stop. In that case, the activity would have to be fragmented with some of the load broken off onto other frequencies. So, those two issues - first, wide-area operation is not appropriate for localized use (the communication is only relevant to 1 square mile or so, not 500), and system activity approaches the point where there is lno opportunity to share the empty spaces between transmissions. Conventional works exceptionally well in those situations.
 

radioman2001

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New York City is an animal to itself. There is no other city with the number of radios and agencies. There is also no reason for a PD officer or anyone else that has to be heard all over the entire city. They are mainly concerned with maybe a 1-2 square mile area, and that may encompass tall buildings that shield radio signals. Most of the base repeaters located in NYC are less than 30 watt, and are set up just to cover that particular area. Also Motorola tried to get NYPD to go trunking in the late 70's to early 80's, and at that time their Type I system did not have enough ID's for the number of radios they have. Trunking does one this that's good, it shares frequencies for large number of users over a large area. Something NYC doesn't need for it's emergency services, but is used for other agencies. There are 2 Type II 3600 bd trunking systems in NYC an 800 MHZ built in the late 80's which has already exceded the maximum number of ID's allowed and a new 480 MHZ system that has taken over a lot, but not all of the conventional agencies that are located in the city. They have even cross patched the 2 systems together to appear as one under certain conditions. Conventional will never crash and that's the main concern with NYPD and FDNY.
Oh, one other thing they have another radio system that is used extensively by most agencies, but not NYPD and FDNY. They have their own data network that uses Blackberry terminals.
 

lafd55

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Yea, to summarize in my eyes... trunking systems do not like big steel and concrete building... I know of 800mhz trunked systems where there are dead spots in close proximity to a tower all because there is a little bit of concrete and steel blocking it...
 

Thunderknight

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Yea, to summarize in my eyes... trunking systems do not like big steel and concrete building... I know of 800mhz trunked systems where there are dead spots in close proximity to a tower all because there is a little bit of concrete and steel blocking it...
Trunking has nothing to do with building penetration. A conventional repeater with the exact same configuration would have the same dead spot.
Also, 800 does not equal trunking. There are plenty of conventional 800 systems.
 

W1KNE

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Most of the base repeaters located in NYC are less than 30 watt,
Are you talking about the NYPD 476-477 MHZ repeaters?
The majority of those are licensed around 200 watts, and are located on pretty substantial buildings.
 

phillydjdan

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The other thing you should consider is that a trunking system is controlled entirely by computer. If that computer crashes (which is always a possibility) then the system is basically useless. A conventional repeater is simply a bunch of electronic components, like your stereo. You could liken it more to an appliance. Which would you rather trust when you're being shot at, a computer or an appliance? I personally would rather trust the applaince.
 

radioman2001

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NYPD Precient frequencies are all 30 to 50 watt stations (to keep the noise floor low) located somewhere within that Precient. There are also backup stations for adjoining Precients located there so if one site goes down they can switch over to an adjoining site. Most locations I saw had anywhere from 3 to 4 transmitters and 6 to 8 voting receivers per site. All the stations I have seen and have worked on were all 30 watt connected to 7/8 coax to a 5db stick. The voting receivers were connected together to a multi-coupler and a separate antenna or duplexed into one of the transmitter antenna's .The hi power stations you quote are probably for City-Wide transmitters or Special Ops channels.
Please state meaning for substantial buildings, since most of the inner city has an average building height of 30-40 stories. Again in NYC one size doesn't fit all, the NYPD radio shop has some excellent engineering folk who over the years have built and rebuilt their systems to be resilient and work in all kinds of adverse conditions. In all the years I worked EMS down there I can only remember once the Precient channel that I was working in going down and was quickly recovered by an adjacent Precient transmitter within minuits not hours.
Their attitude in the radio shop is KISS, and I whole heartly agree
 

GTR8000

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Are you talking about the NYPD 476-477 MHZ repeaters?
The majority of those are licensed around 200 watts, and are located on pretty substantial buildings.
I'm not sure what licenses you're looking at, but the overwhelming majority of NYPD T-Band licenses are between 50-75 watts and are not located on "substantial" buildings. It sounds to me like you're looking at the maximum ERP, not the actual output wattage. Also keep in mind that just because a license allows for 75 watts, that does not necessarily mean they are using that much wattage in practice.
 

n5ims

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The other thing you should consider is that a trunking system is controlled entirely by computer. If that computer crashes (which is always a possibility) then the system is basically useless. A conventional repeater is simply a bunch of electronic components, like your stereo. You could liken it more to an appliance. Which would you rather trust when you're being shot at, a computer or an appliance? I personally would rather trust the applaince.
In most trunking systems (that are properly designed at least), when that computer crashes, the system moves to "failsoft" (Failsoft - The RadioReference Wiki), which basically turns it into a group of conventional repeaters. When in this mode, the repeater controllers activate a special tone to signify the change to failsoft mode and the user's radios will associate the selected channel with the repeater pair assigned to that channel (or give the "fail" beep to indicate that the selected channel doesn't have a failsoft channel assigned to it.) Most often the dispatch operators will announce the failure and provide instructions (actually a reminder since these instructions are part of the training program) on how users should communicate during the failure period.
 

FrankRaffa

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The only training program you should need to operate a radio in the public safety field is the ON/OFF and PTT buttons. Anything more than that requires more effort than is needed to do your job.

I realize I am virtually alone in this opinion but I have said it since the beginning: trunking has no place in mission critical functions. There are too many links in the chain that can fail.
 

JoeyC

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The only training program you should need to operate a radio in the public safety field is the ON/OFF and PTT buttons. Anything more than that requires more effort than is needed to do your job.

I realize I am virtually alone in this opinion but I have said it since the beginning: trunking has no place in mission critical functions. There are too many links in the chain that can fail.
Don't be silly. Even a conventional repeater can malfunction from time to time. Power outages? Phone line failures?
Trunking has worked effectively for decades, and in a failure resorts to failsafe mode which operates essentially as your conventional repeater would.

In Mayberry in 1955 they may have been able to get away with using just one channel simplex, but in Brooklyn as I'm sure you're aware, the need to change channels, volume, and charge and replace batteries is necessary. Don't train them to do that? Very poor public safety preparedness. :mad:

If any more training other than knowing where PTT, ON/OFF is not necessary means you don't really need a radio in the first place.
 
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ssixsixsixx

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NYPD Precient frequencies are all 30 to 50 watt stations (to keep the noise floor low) located somewhere within that Precient. There are also backup stations for adjoining Precients located there so if one site goes down they can switch over to an adjoining site. Most locations I saw had anywhere from 3 to 4 transmitters and 6 to 8 voting receivers per site. All the stations I have seen and have worked on were all 30 watt connected to 7/8 coax to a 5db stick. The voting receivers were connected together to a multi-coupler and a separate antenna or duplexed into one of the transmitter antenna's .The hi power stations you quote are probably for City-Wide transmitters or Special Ops channels.
Please state meaning for substantial buildings, since most of the inner city has an average building height of 30-40 stories. Again in NYC one size doesn't fit all, the NYPD radio shop has some excellent engineering folk who over the years have built and rebuilt their systems to be resilient and work in all kinds of adverse conditions. In all the years I worked EMS down there I can only remember once the Precient channel that I was working in going down and was quickly recovered by an adjacent Precient transmitter within minuits not hours.
Their attitude in the radio shop is KISS, and I whole heartly agree
Agreed. With keeping the 400Mhz systems the NYPD also has the option to have a substantial amount of older radios that could be used as extras such as the Motorola Sabers, which they have a TON of in storage. Biggest problem there is that they dont have a decent amount of chargers availible to actually charge the batteries. Now that they have mostly switched entirely to the Vertex Standard radios, so long as everything is still working on the 400Mhz band, the older stuff will still work. Back in the days of the Motorola MX350's, one could not stand in the southern end of Brooklyn and be able to key the repeaters in the Bronx, but now you can transmit over almost any frequency from almost any location within the city. Those MX350's were great radios! They worked just fine within their assigned areas and they were impossible to kill. If your radio didnt work, just hit someone over the head with it and you were back on the air. If that didnt work... hit em one more time! And if someone still had one, I would guess that it too would still work on the current system.
 

radioman2001

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Yes the MX's were great, I doubt they would work other than for a receiver. NYPD did some extensive work on their system in the late 90's to eliminate unauthorized access to their repeaters( by perps using ICOM U-16 radios) by using multiple PL's, non standard PL's like 97.4 which is a GE tone ,split PL's and even non standard TX offsets. The PL's used to be assigned based on borough, (I don't remember them all but Manhattan was 103.5 and Queens was 114.8) but now they have splinter PL's and different TX and RX PL's. That's one of the reasons they went Vertex, as Motorola at that time refused to build them a radio that would do more than 16 different PL's in it. Motorola really misjudged NYPD on that one, I'll bet the resident salesperson is no longer there as a result
I could be wrong. but I thought the SE5000 used the same batteries and accessories as the analog saber, that was the reason it was built. That and to get back with NYPD after the Vertex debacle.
Getting back to the original OP topic, unless you need multiple talk groups to cover a large area any frequency can be converted to non trunked analog use. With the narrow band deadline approaching after 1-1-2013 you can apply for new channels in any band a probably get them.
 
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SCPD

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Yes the MX's were great, I doubt they would work other than for a receiver. NYPD did some extensive work on their system in the late 90's to eliminate unauthorized access to their repeaters( by perps using ICOM U-16 radios) by using multiple PL's, non standard PL's like 97.4 which is a GE tone ,split PL's and even non standard TX offsets. The PL's used to be assigned based on borough, (I don't remember them all but Manhattan was 103.5 and Queens was 114.8) but now they have splinter PL's and different TX and RX PL's. That's one of the reasons they went Vertex, as Motorola at that time refused to build them a radio that would do more than 16 different PL's in it. Motorola really misjudged NYPD on that one, I'll bet the resident salesperson is no longer there as a result
I could be wrong. but I thought the SE5000 used the same batteries and accessories as the analog saber, that was the reason it was built. That and to get back with NYPD after the Vertex debacle.
Getting back to the original OP topic, unless you need multiple talk groups to cover a large area any frequency can be converted to non trunked analog use. With the narrow band deadline approaching after 1-1-2013 you can apply for new channels in any band a probably get them.
I am born and raised in London, England and all of our emergency services use a trunking system... and they only have to communicate in a certain area also... works fine for them! And that's a police, fire and EMS + many other users for a population of 7,825,200...

The USA is behind the times in the radio communication area... except an area of North American that moved to the most advanced radio system in the world... TETRA... P25 is still old technology compared to what TETRA can do. TETRA is used by around 120 coutiries around the world. Beat that P25... ;)

But, I will say P25 radio TX at a higher power than TETRA so it's needed for the USA where as TETRA works for countries with a smaller geographic footprint... however China uses TETRA and it works well for them.
 

radioman2001

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You are talking about 2 different worlds, the TETRA you have is mostly privately owned, not a common practice here in the U.S. YET. I don't believe that a private company should control the radio comms of Public Safety. P-25 is not a commercial format, even though it is becoming one. It was designed by Public Safety professionals for Public Safety after many years of testing. It relies more heavily on error correction, because it needs too. If you lose a word or 2 on a private call it's no matter, but in Public Safety that would be a issue very quickly. There have been plenty of TETRA failures right in London that have made international news. There have been very few here with P-25 none of which I am aware of made international news. TETRA has it's uses but in my opinion it hasn't grown up enough to compete with P-25 as a true Public Safety radio format. TETRA is very infrastructure intense, meaning it needs a LOT of radios sites, more on the order of a cell system, and other than it is being unmonitorable, which China I'm sure wants due to it's draconian attitude towards it's public.
TETRA may have it's place in commercial and industrial communications, but I wouldn't want it for Public Safety.
Oh BTW NYC Transit is PLAYING with TETRA right now, I don't have anymore info other than that.
 
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