Railroads and NXDN

PJH

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So, every so often this comes up.

Here is a quick lesson on what is going on.

Back in the day, the AAR was looking for a standard digital format when public safety went out with the P25 standard for voice communication.

The players for PS were essentially Motorola with their digital CODEC and DVSI with the IMBE CODEC. After some time, APCO decided on IMBE as the standard.

Sometime after, and with the narrowbanding coming, AAR did the same thing. The players were Motorola and "everyone else". Motorola had a good business with the railroads for decades. The "clean cab" standard that Motorola made radios of for the locomotives - was pure gold.

When the digital standard for AAR was looming, again Motorola and "everyone else" submitted their products. P25 based for Motorola and what would become NXDN/IDAS from those guys. However, Motorola also wanted a commitment from the industry for x amount of radios per year purchased to make it worth their while. At several thousand dollars a unit, the industry gave them a big FU.

I do not know the details of the selection, but the NXDN codec was chosen.

For awhile, the AAR stated that communications would be in the NXDN format. However, the techo geeks never really bothered to talk to the railroads.

Many, if not most field equipment is operated or responds to DTMF commands and/or PL tones. Dispatcher radios, remote switches, derails, trackside detectors and countless other pieces of equipment.

NXDN and DTMF are mutually exclusive, and replacing millions of dollars of wayside equipment just isn't going to happen. Not even in the long term. Due to the nature of how things actually work on the railroad, there just isn't anything that compares to what analog/signally does.

AAR backed off on the "requirement" years back, but in the railfan/scanner community they believe that its still there. There is nothing to *prevent* its use, but its *not* required. Its *only* required at interchange locations *if* digital voice is to be used between two different railroads.

Unless agreed upon and equipped, the AAR plan is to be used.

Some smaller railroads use it, some regionals ones do. I also am personally aware of some regional ones using commercial trunked systems - and that's ok. However when interchanging, they will use standard AAR channels.

There are many, many locomotives out there that do not have NXDN cab radios. Railroads do not assign the general pool locomotives by the radio capability. In fact, most locomotive radios are not tracked to the units so it could have one, one day, but then removed and placed into another one the next. They are designed to be easily replaceable.

Eventually they will be replaced one way or another, but that's the easy part.
 

mmckenna

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However, Motorola also wanted a commitment from the industry for x amount of radios per year purchased to make it worth their while. At several thousand dollars a unit, the industry gave them a big FU.

Motorola has had a habit, in the last decade or so, of shooting themselves in the foot like that. When MotoTrbo was rolled out, they specifically blocked the NPSPAC 800MHz channels from the radios. At the time I was in the market for replacing my aging SmartNet system. I trialed at Trbo system for a while, but Motorola refused to let NPSPAC channels be used in their radios. You couldn't program them in. When I asked Motorola about this, their answer was "If you are using NPSPAC channels, you must use P25".
So, I went with a Kenwood NexEdge system, and saved a lot of money in the process.
While not even a drop in the Motorola bucket, it's these sorts of things that have led them to lose market share. Their attitude seemed to be that they could force the markets in the direction they wanted. They didn't realize they had competition.
 

radioman2001

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While Mot may have wanted a commitment of X number of radios for their engineering costs, I believe it was more of this what we have to offer and that's it take or leave it. They do this constantly and you can think about how Mot went ballistic when they lost the New York City Transit Authority contract because they did not have or would not build a Tetra radio for them, or NYPD trying to shove the XTS series radio down their throat a few years back. Both times they lost out for being STUPID, NYPD went Vertex and NYCTA went to another vendor for Tetra. As a foot note Mot tried to entice NYCTA with the offer of we will build a radio if we get the bid, even though they had no product at the time. NYCTA turned them down, then Mot went nuclear calling in the FCC to try and shut the project down not realizing that the NYCTA freqs were not P.S. and not subject to P-25 mandate. There have numerous instances where Mot dropped their price 40% when they lost to another bidder.Their hold on the 2-way P.S. market is slipping.

Competition in the markets now give agencies more choices at a lower price, that's why they are fighting the future use of LTE, since anyone can build a handset removing their lock on the market.

Quote"
AAR backed off on the "requirement" years back.

They didn't back off the Class I RR's said we are not going NXDN and that's that. It was voted upon at a meeting sometime in 2014.

Quote"
I do not know the details of the selection, but the NXDN codec was chosen.

It was chosen to screw Mot for the abandonment of support for their RR radios AND when Icom and Kenwood came in a better Codec the Ambe II with an open format that uses less bandwidth, and any radio manufacturer could use they chose it. A no brainer .

As this other post suggests most RR's and agencies will NOT be going NXDN in the foreseeable future.

https://forums.radioreference.com/r...ll-hear-rr-comms-clear-csx-2.html#post2847897
 

PJH

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What I forgot to mention as well, Motorola (at the time, I’m fuzzy with the “NXDN Forum”) is that Motorola would have had to pay royalties to them and incorporate another competing product into their own.

I don’t recall when Motorola has ever done that, without purchasing the patent or company.

In the case of NYC, Motorola bought Vertex and the Vertex proper radios are slowly being killed off. At some point it will all be back under Motorola name.

As an aside, the SSE5000’s are still alive and well. Many of the deployed auxiliaries carry them.

Back to Motorola and railroad, they are trying to push DMR onto the smaller railroads and industrial ones.
 

radioman2001

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Quote"
Motorola would have had to pay royalties to them and incorporate another competing product into their own.

I don't believe the royalties costs involved in building a NXDN product was anymore than what they paid DVSI for P-25 in fact it would be less. As far as a competing product they are different price line radios and could have been made.

BTW the SSE's were only around 40-50 radios, which in the grand scheme of radios for NYPD isn't much compared to the 6000 Vertex they bought over the life of the contract. Vertex even made a special VHF one for our MTA PD. They were Mot last attempt to keep NYPD which had asked for a radio that used the same batteries and accessories as the Saber/Astro Saber, and do more than the number of PL's the Saber did. Another reason was NYPD was looking for a radio that did a PL that the Icom U-16 couldn't do (97.4hz). They were having all kinds of problems with fake calls in Brooklyn at the time. Yes they bought Vertex (and sold it), after they lost the bid, but they were definitely shocked to learn they got booted in you know where because of their arrogance.

Quote"
Back to Mot and railroad, they are trying to push DMR onto the smaller railroads and industrial ones.

Mot themselves is not, the local dealers are, and as I have stated before the AAR won't approve a co-ordination with DMR, the RR's are doing it themselves after the fact. Other than the Railcom Trainmaster XD there is no real Mot DMR RR radio. Next year the trainmaster is going to a Kenwood NXDN chassis and no more XRP, or as an option. I have already pre-ordered one for evaluation.
 

slapshot0017

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I really appreciate this thread. It gives great insight into this whole situation. Being involved in the industry I can say that analog is really the only way to go for the railroads. NXDN is nice and cleans up the audio, but when you're switching a massive yard with a few crews building their trains within spitting distance of each other they listen for each others voices other than their identifier. It kind of becomes a free for all, but it works. Digital voice makes a mess of it. In my personal opinion I think LTE would be even more dangerous than standard digital voice and that's everywhere. I don't see it as a reliable solution, but that's me. Anyway thank you guys for bringing this to a more organized view.
 

20yrsMilComm

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NXDN

Just gonna put this out there... I work for one of the Class I Railroads, (which one will remain confidential). When the narrow banding mandate was initiated my company vot rid of all Motorola radios and had upgraded whatever kenwood radios that were left. Now we run with Kenwood NX-700HK radios that are capable of using NXDN but all that ever gets used in analog. There 8s 9ne group with NXDN channels programed but never used. Any switches that are remotely operated by a trainman is in analog form using DTMF code.
 

n4jri

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I've found exactly two active NXDN rail freqs active in VA. They are used for maintenance and shop traffic, and not for train movements.

73/Allen (N4JRI)
 

scan-pa

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Here in SC PA, Have only heard 5 different AAR 3xx NXDN Channels in use. It was used mostly for Railway Inspection and some Maint. to shop chat... since that day, it has been very far and few....
 

cbehr91

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Bellevue (Ohio) car dept. using AAR channel 376 (160.7325).
 

20yrsMilComm

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Well even the nxdn capable radios that that we recieve, either it be a moble radio mounted in a trck or an HT, come with some nxdn programed channels. These channels range from 3xx up to the lower 4xx. Not sure exactly how many channels are programmed in because I've never counted them and I'm sure that I can find what all the frequencies are as well. Which rail road is that Ohio card department in? And in PA?
 

20yrsMilComm

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So the group name is RRDig (rail road digital) and the channel names are from 307 up to 487 and are all NXDN conventional without RAN
 

scan-pa

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And yes RAN codes are being used. So far RAN 2, 3, 5 seen in use by NS. And by various railroad Law Enforcement agencies.

Sent from my SM-G935V using Tapatalk
 

N4VKF

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I've found exactly two active NXDN rail freqs active in VA. They are used for maintenance and shop traffic, and not for train movements.

73/Allen (N4JRI)
CSX has been quiet in my area. Do you think they moved to NXDN on the rfp subdivision?

Sent from my SM-G950U using Tapatalk
 
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DaveNF2G

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New NXDN repeater just popped up near Albany, NY, on AAR 13 (in) and 80 (out), RAN 0.

I haven't heard enough traffic yet to pin down a user. It seemed to appear first yesterday, or at least that is when I first heard it and I monitor rail channels almost constantly.

Norfolk&Southern is not a big presence in this area. The signal is very strong in Rensselaer, so I suspect it is connected with the Amtrak Turbo Shops. Still listening...
 

Ronaldski

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I will throw a wrench in this. Here in Mid MI, Lake state railroad is operating on 160.710 with mototrbo at their main yard and is licensed all along their route for it. I updated the MI rail database a few weeks ago. Their yard near me is still analog.
 
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DaveNF2G

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I found a listing for Channel 80 to CP Rail (which bought out D&H years ago) in Watervliet.

It is definitely a repeater. I could hear both frequencies.
 
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