NJICS Municipal Migration Discussion - Statewide

[BIODTL1997]

very foolish, shame on them, what happens when that system ****s the bed and it will.

With all due respect, the NJICS system has been quite reliable and is a really well-designed and supported state-of-the-art network. I think shaming an agency for joining the dozens of other well-served organizations is going a little too far which seems to be based on the fact that you can't listen to them now. But this isn't a thread to discuss personal issues so let's carry on with the technical info, please.


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[mondaro]

Doing communications sir for many years, its a flawed system, make no sense not to have a back up
that's my only point here just ask some of the Essex County Fire Departments who use it now how they like the system.
My point wasn't that you can't hear them any longer,

 

[slapshot0017]

Doing communications sir for many years, its a flawed system, make no sense not to have a back up
that's my only point here just ask some of the Essex County Fire Departments who use it now how they like the system.
My point wasn't that you can't hear them any longer,

I'm with you on this system...

 

[902]

Doing communications sir for many years, its a flawed system, make no sense not to have a back up
that's my only point here just ask some of the Essex County Fire Departments who use it now how they like the system.
My point wasn't that you can't hear them any longer,

The network in any networked system is the biggest vulnerability. There are discrete non-trunked repeaters on the 8TAC channels, maybe some on 700 MHz, and a trailer, but in a widespread outage, there's got to be some wrangling about who gets what. These things are great for every-day communications, but there has to be a lot of consideration for "the very bad day."

I thought they got the audio issue the guys in the big Essex Co. FD were concerned about all straightened out. Is that still a problem?

 

[Analogrules]

I also agree with Mondaro. When it comes to NJICS or any digital Trunked system. It was foolish for many departments to completely abandon their VHF and UHF conventional systems completely. If there is ever an outage of NJICS, many agencies will be screwed! I think most Newark FD officers would tell you their radios worked a hell of a lot better on VHF.

 

[W2SJW]

Apparently people have no understanding of how failsoft mode works when a TRS site controller goes down...

 

[APX8000]

Apparently people have no understanding of how failsoft mode works when a TRS site controller goes down...

Yep


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[CJS2]

Apparently people have no understanding of how failsoft mode works when a TRS site controller goes down...

Finally a voice of reason.

 

[902]

Apparently people have no understanding of how failsoft mode works when a TRS site controller goes down...

Actually, I do. Pretty well.

Under ideal conditions, failsoft puts everyone on a common, pre-programmed frequency which acts like a community repeater. Great.

NJICS IS NOT a simple, single-site SmartNet repeater, and its zones may have combinations of simulcast. So, let's say a localized incident has also affected the closest simulcast site. That site loses its link to the rest of the system. It's isolated. That can go into a fall-back mode, but it will still be on the same set of frequencies, if both remain operational, destructive interference is now likely between the independently operating sub-systems.

Situation 2, let's say there's some MIJI attempt. The reference oscillator may either be warped to be out of tolerance for simulcast, or may free-run out of tolerance, causing destructive interference.

I'm not advocating for VHF. VHF in NJ is an absolute horror show. UHF is also a no-go just about everywhere now, unless one were to "buy" frequencies at auction (which NJ has done). What I do advocate for is an in-band network agnostic fallback as a means of resiliency and recovery.

Ideally, what I would like to see is the distribution of stand-alone 700 MHz mutual aid repeaters throughout the served areas. Those might be able to serve as failsofts, or, better yet, the equipment be programmed to default to the conventional mode in the absence of a control channel, or if the control channel corrupts beyond the set threshold value. Actually, this would be a great application for P25 phase 2 - if TIA would have extended TDMA into conventional operation (there's no practical reason why it could not). Using the model DMR has proven, slots 1 and 2 in a 2/TDMA conventional repeater could each simultaneously host fallback modes. That would be both spectrally efficient and cost effective. But the industry players have only proposed 2/TDMA as a trunked solution.

 

[ansky]

I'm not advocating for VHF. VHF in NJ is an absolute horror show. .

Can you elaborate? Why is VHF a "horror show"? I have been listening to New Brunswick Fire for over 20 years on 154.325. They sound great and I can even hear them from 30 miles away.

 

[Alarmguy]

Apparently people have no understanding of how failsoft mode works when a TRS site controller goes down...

This.

 

[902]

Can you elaborate? Why is VHF a "horror show"? I have been listening to New Brunswick Fire for over 20 years on 154.325. They sound great and I can even hear them from 30 miles away.

Absolutely.

The 19 dBuV/m F(50,10) "interference contour" of New Brunswick provides some degree of interference to:
154.325 MHz
KNBY464, NHRCA, 30 mi.
KSJ562, Red Bank, 22 mi.
WNMB659, Hillsborough Twp, 8-13 mi.
WNZB672, Newark Fire Department, 21-22 mi.
WPKH556, Washington Twp, 25 mi.
WPVJ284, Jackson Twp, mobile repeaters, 25 miles away with a 25 mi. authorized radius of operation
WQN244, Washington Twp, 24-28 mi.
WQPX300, Warren Co., 33-47 mi.

You can see that the frequency is reused in Hillsborough Twp at a site 8 miles away. There is mutual interference if many of these need to use the frequency simultaneously.

If you mapped coverage for each of these, they are all blobbed over each other with significant overlaps, like you dropped a bunch of coasters and they all ended up in a stack overlapping each other.

Their input is just as cluttered, if not worse. Add a digital signal to that and it could completely interfere with their system.

It's not my intention to apologize for 700 MHz, but there you have this entity called a Regional Planning Committee. There's one covering Northern NJ, NYC, and part of CT (Region 8) and one covering Southern NJ, Philadelphia, Delaware, etc. (Region 28). These bodies have pre-coordinated how and where channels are used and review engineering documentation so that at least 80% of the energy intended to cover a specified area stays within that area - and that no energy goes into a reuse area or degrades another co-channel or adjacent channel licensee. That's something neither VHF nor UHF (or even most of 800) ever had.

 

[RadioDitch]

Unitrunker data shows Plainfield Police as 100% encrypted. I'll investigate as to whether Elizabeth and Linden Police are encryption capable with a few sources.

All of the talkgroups in Union County are encryption capable. Plainfield is supposed to be full time, Elizabeth is going to remain selectable...for now...

 

[BIODTL1997]

Very interesting info here. I apologize, Mondaro, for portraying any snarkiness. I guess I had not taken into consideration any site outages as I'm locked into the WO site 95% of the time and can't remember hearing any comm outages since its turn-up. Can't say the same for the Morris county system though. (Who may be the most frequent flyer on UTAC7)




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[mondaro]

That is the great about Radio Reference including myself is learning from the other people here.
I am on the job so I get to talk to the fire departments that have NJICS the good, bad and the ugly.

Happy Holidays All !!

Tony

 

[KDD904]

BIODTL1997 (Can't say the same for the Morris county system though. (Who may be the most frequent flyer on UTAC7)) Just FYI, the ongoing issues with Morris County aren't radio system failures, but co-channel interference from WFDC in Arlington VA since they went digital, during tropospheric ducting, when it exceeds the threshold for shutting off sites/frequencies. The FCC hasn't been much help since both systems are operating within their technical parameters. Regarding another comment on backups, there are independent, geographic conventional repeaters for Morris were the trunked system to suffer a catastrophic failure, but these are no help during tropo-ducting since they are in the same frequency/TV channel range. UTAC47 is not T-Band so it works. They are continuing to seek resolution.

 

[richee2000]

can you please list the independent, geographic conventional repeaters for Morris county frequencies ?

thanks!

 

[902]

BIODTL1997 (Can't say the same for the Morris county system though. (Who may be the most frequent flyer on UTAC7)) Just FYI, the ongoing issues with Morris County aren't radio system failures, but co-channel interference from WFDC in Arlington VA since they went digital, during tropospheric ducting, when it exceeds the threshold for shutting off sites/frequencies. The FCC hasn't been much help since both systems are operating within their technical parameters. Regarding another comment on backups, there are independent, geographic conventional repeaters for Morris were the trunked system to suffer a catastrophic failure, but these are no help during tropo-ducting since they are in the same frequency/TV channel range. UTAC47 is not T-Band so it works. They are continuing to seek resolution.

In this case, the FCC *IS* the problem. The Wireless Telecommunications Bureau (which later spun off the Public Safety Homeland Security Bureau) was in charge of the Part 90 frequencies for land mobile radio systems, while the Media Bureau is in charge of television frequencies. During the DTV transition, they could have cleared 14 - 21 and there would have been no issues for the many NJ T-Band licensees. But, one is independent of the other, and they don't seem to speak to each other. Their interactions also never take tropospheric ducting into account. The big problem is that TV broadcasters in some cases are sending over a million Watts of RF which is being reflected and coming back down much further than it was intended. Usually other land mobile radio systems are manageable to an extent, but TV stations are strong enough to present a prolonged signal, locking out channels, blocking requests for channel grants on the control channel, and pretty much sinking the entire system. Most T-Band systems work extremely well under normal conditions. It's a shame. The best case is to "borrow" another T-Band channel and have two sets that can switch over. There's a possibility that another TV station would be ducting in at that time over the other set of channels, too, plus it's expensive.

The other shame is the "giveback." That's NOT the FCC. They're in a quandary over what to do about that, too, and gave up 24 channels in 700 a year or two ago to "help" migrate the several hundred T-Band ones (yep). That's squarely a directive from Congress that was signed into law by the President. Many of these systems aren't old at all, and many of them are still loading. Yet, unless politics prevails, they'll all need to vacate and "go somewhere else." Many are fleeing to 700 MHz. That's fine, and it represents the opportunity to tie into the much bigger network with a local sub-system that's tailored in coverage (remember my network vulnerability statement, though, these things are wonderful tools for their users when they're 100%, but always have a plan B). But in a lot of cases, it's double the work and expense - even if whomever the successful bidder can finance the move.

 

[ten13]

Has anyone heard anything about Jersey City moving to the NJICS?

I believe they are now licensed for the 700 frequencies but, relatively speaking, they just moved to their present UHF Digital Trunk system, a system that no one appears to be happy with, especially the cops.

 

[K9one]

Jersey City 700MHZ

The only 700 mhz frequencies that I am aware of being issued in the area of Jersey City was for Hudson County for a possible new system for the county.

Jersey City at the beginning of this school year just added the Board of Ed to their system and had to buy all portables for them.

I do not see jersey city moving off their system anytime unless they are forced too, the UHF system is not that old and would it be cost prohibitive.