Rockland County 700mzh P25 PII system range/ First impressions

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FF153

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On another thread which is now closed there was discussion regarding the range of this new system. I had the opportunity to play around with a portable on this new system and had excellent results with reception/range and I thought I would share some of my first hand experience. Just a note I know that some radios will "lock" after they reach a certain distance from the nearest tower this radio was not one of them. I was able to go all the way up to Gander Mountain in Middleton in Orange County with crystal clear reception (to be expected on a digital system) and all the way down to Newark NJ with crystal clear reception. I have not once lost signal with this new system. Also to note a good friend of mine was in Connecticut and was able to talk. I believe the question in the original thread was if someone in Warwick New York with a scanner capable of monitoring the P25 Phase 2 system would be able to hear what was I happening. I was at the Warwick Police station and I had crystal clear reception. So in response to your question I believe with out a doubt you will be able to hear what is happening.

I have only been able to use these radios on a preliminary level but so far I must say I am impressed. At first I thought it was going to be a S**T show but I was happily proved wrong. I still believe the true test is going to be when the FD's get on the system to see how it handles the additional traffic. I am also anxious for the next "big" incident that requires Police Fire and EMS to work together and to see in the interop tlk groups will be utilized.

Also in one of the posts on the other thread I mentioned before someone said that the antennas for the 700mzh system are directional antenna (only broadcast in one direction), I maybe wrong but I thought the 700mzh antennas will be omnidirectional (broadcast in all directions ) but the antennas for the UHF paging for the FD's will be on directional antennas. Correct me if I am wrong but this is just what I herd!

Thanks,
Kevin
 

62Truck

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Something I just wanted to point out. Being that is Fall and almost winter, most trees have lost their leafs. Leafs will attenuate signals higher up in frequency as you go. I have noticed this on my 900 Mhz repeater. In the spring you might notice a decline in range/reception.
 

FF153

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That is a very good point that you raised! I had not thought about that. When I went up to Warwick there were still leaves on the tree's so we know it will at least hit Warwick Whens there's leaves I cant speak for any of the other places I went to since they were recent trips.
 

62Truck

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That is a very good point that you raised! I had not thought about that. When I went up to Warwick there were still leaves on the tree's so we know it will at least hit Warwick Whens there's leaves I cant speak for any of the other places I went to since they were recent trips.

I'm a personal friend with the system admin, I would expect the system to work very well ;)
 

studgeman

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Just a quick comment on the antennas. I think you will find that most, if not all of the antennas for the 700MHz are directional, and I would guess there is extensive use of panel antennas. Though several of these antennae may be arrayed to create an omni pattern off the tower, the antennae themselves are directional. Passive Intermod, plus controlling contours though downtilt have played a large part in the engineering design of the system since day 1. There are enough engineering nuts on these boards I thought I would mention it, even though it is essentially the functional equivalent to the man on the street.
 

APX8000

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Adam is a top-notch guy and really takes pride in making sure the system works as designed, That is one of the reasons why the system works so well. I was told he walked every square inch of the mall checking portable interior coverage. I only hope we can borrow his knowledge when Orange County builds out their system.
 

FF153

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Studgeman thanks for the replie it was very informative!
And signal-zero Yeah Adam definitely takes pride in what he does! It is great for Rockland! I'm sure he will lend a hand to Orange when they design there system.

Sent from my SPH-L710 using Tapatalk
 

radiomanNJ1

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I wonder why you would think putting the volunteers on the system will change it's performance?

it is good that Rockland finally got their act together after several other plans fell apart including having to relinquish UHF t channels.
N2ACF is good at what he does.
 

ff026

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The other plans didn't fall apart. The T band system was on the drawing board. Early in the system design phase noise floor readings were taken. The readings were not very good and would have made some frequencies unusable. Around the same time 700 MHz opened up so the design was shifted to that band.
 

radiomanNJ1

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Perhaps you were not around when the first systems were proposed. The Tband idea was 20 years ago.

The other plans didn't fall apart. The T band system was on the drawing board. Early in the system design phase noise floor readings were taken. The readings were not very good and would have made some frequencies unusable. Around the same time 700 MHz opened up so the design was shifted to that band.
 

ff026

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No I've been a member of the committee since day one. Their has been only 1 T-band system proposed. Like I stated it was changed to 700. The public safety radio committee was started almost 20 years ago. Nothing happens overnight. We were fortunate we had delays because of those delays we now have a very robust system now. The term " technology creep" actually worked to our advantage.
Were you a member of the committee? Or a member of Rockland public safety? You seem to be a fountain of misinformation.
 

radiomanNJ1

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Yes, Public Safety. I am aware of the tband issue and I agree that it is better that we ended up with a 700 system rather than tband like our neighbor Bergen's and a possible 9 year life left. Of course that system is way too small to handle their county and most of the agencies will not join it anyway.
 

902

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Just a quick comment on the antennas. I think you will find that most, if not all of the antennas for the 700MHz are directional, and I would guess there is extensive use of panel antennas. Though several of these antennae may be arrayed to create an omni pattern off the tower, the antennae themselves are directional. Passive Intermod, plus controlling contours though downtilt have played a large part in the engineering design of the system since day 1. There are enough engineering nuts on these boards I thought I would mention it, even though it is essentially the functional equivalent to the man on the street.
It's a Region 8 Regional Planning Committee requirement so that frequencies can be reused throughout the metropolitan area. Each of the transmitters can be fed into power dividers or couplers which provides a certain amount of energy into each antenna. The antenna is plotted with an azimuth and horizontal beamwidth, then the plots of a certain contour are drawn. A certain percentage of signal level has to stay within the county boundary + a small buffer area. If not, then the antenna has to be reoriented, tilted, lowered, or the power reduced... or all of the above... or maybe it's just not doable at all, and then the site has to be changed. It's called the "responsible radiation control" test. Then they have to look at co-channel and adjacent channel effects. It takes a very long time to build a model then tweak it if it fails.

The idea is that the energy is sent into the area that requires service, not out to the horizon, like we all used to do with older systems. Notice that these older systems usually had great scanner reception from way out, but sometimes had problems in town. That's why. The energy was going places where it didn't do the guys in the street any good. You'll see that on every 700 system in Region 8 (around NYC). It's not necessarily how a T-Band system is made, nor is it necessarily how an 800 system is made.
 

902

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Yes, Public Safety. I am aware of the tband issue and I agree that it is better that we ended up with a 700 system rather than tband like our neighbor Bergen's and a possible 9 year life left. Of course that system is way too small to handle their county and most of the agencies will not join it anyway.
That depends. There can be some very adequate systems with low channel counts, given 2/TDMA and transmission trunking (where the system doesn't hang on waiting for another user). One manufacturer's solution for this is to add more channels. The time is wasted on hang-time. Their argument is that there does not have to be another channel grant. BUT, there has to be a PTT ID, so that argument (to me, at least) is invalid. Another manufacturer uses transmission trunking all of the time, and the channels roll through the system and become available for another transaction right away. That kind of system is more efficient and might be able to accommodate countywide traffic without any problems.

Think about it this way - look at all the VHF or UHF resources that lie fallow most of the day. One town can have a half-dozen (or if you're one particular town I'm thinking of, you can have three dozen that get used maybe 3 times a year). Then someone talks, but if you used a timer, you wouldn't have more than 20 minutes of traffic from one user a day. That principle works for trunking. The resource gets used constantly now and rarely lies fallow unless there were no calls in the queue or the office is closed.

And, on a side note, I'm torqued. When I lived in Bergen County, nothing like this ever took traction. Now, they finally got their stuff together to start something up, and it's sold out by Congress for a bag of magic broadband beans. Go figure. Hopefully they can find replacement spectrum somewhere other than low band.
 
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