Railroads and NXDN

ElevatorsAndRadios

yarewesog
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Not in NXDN, TT pad is for analog. At least for Icoms

That is simply untrue. I have heard DTMF on an IDAS NXDN voting system. My friend also owns an ICOM F3261DT RR (railroad specific version) and the keypad dials DTMF on analog and NXDN. I have heard his DTMF on my ICOM handheld numerous times on NXDN.


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kb1kvd

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Our railroads Icom's will do DTMF in NXDN and analog. We've tested several years ago on our system for the B&B department.
 

kb1kvd

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I would say it was no worse than using analog. We were testing it for out DTMF drawbridge control indication and for a crossing out in Framingham. We were just testing an idea that Icom at the time didn't seem to sure of the answer. We have had some really great success with shipping 9600 baud data over NXDN to provide wayside health and indications for a couple of interlockings.
 

W2GLD

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When DTMF is sent over NXDN digital, the actual tones are not being sent, rather a digital algorithm is regenerating the tones on the remote end; your ears hear what sounds like DTMF tones, but it’s truly digital signaling. DTMF is also available in P25 as well using the same method. Also many railroads are using NXDN throughout all of North America, but for now, it’s mostly secondary channels such as MOW, Yard, and Law Enforcement operations; common road channels will likely remain analog for several years to come. Also, watch in the coming years as NXDN is also coming to the marine band as well...
 

INDY72

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When DTMF is sent over NXDN digital, the actual tones are not being sent, rather a digital algorithm is regenerating the tones on the remote end; your ears hear what sounds like DTMF tones, but it’s truly digital signaling. DTMF is also available in P25 as well using the same method. Also many railroads are using NXDN throughout all of North America, but for now, it’s mostly secondary channels such as MOW, Yard, and Law Enforcement operations; common road channels will likely remain analog for several years to come. Also, watch in the coming years as NXDN is also coming to the marine band as well...
Quite true. With Marine band now narrowbanding internationally, and NXDN being the standard they are looking at... Expect to start seeing Marine NXDN capable radios soon. Also with railroads using NXDN is digital encryption, which is being used on some Police chans, and administrative chans. It will never be used on yard, MOW, or mainline ops, but the days of always being able to hear the rail road cops are coming to an end.
 

W2GLD

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It will all be 6.25 kHz bandwidth only; 12.5 kHz is a Kenwood propriety mode and is only supported by one radio model of Icom radio; all others have followed the standardized 6.25 kHz NXDN specifications for bandwidth efficiency.
 

INDY72

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Quote"
It will never be used on yard, MOW, or mainline ops,

I wouldn't count on that, we got 18 pair of NXDN freqs from the AAR for just that. I don't see it on mainline or RTC operations anytime soon but for other uses it's already here.
When quoting someone it is wise to actually read entire statement before trying to use it against someone. You should have looked at the sentence just before the one you ran with. "Also with railroads using NXDN is digital encryption, which is being used on some Police chans, and administrative chans. "
 

radioman2001

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Maybe, I misunderstood the statement due to the break in sentence structure and I wasn't using it against anyone, but I was making a statement that still stands as it will be a long time coming before NXDN is used on mainline channels with "E" or not, and far as NXDN "E" on other channels we use it all the time for Fire Operations and Radio Repair, maybe in about 5 years on MOW and Track too. Still have about 4000 HT-1250's out they, and our PD is soon to be on 800/700 with AES.
 

appalling_hauling

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Evansville Western Railway will likely not go this route given they are still attached to CSX who we know isn't exactly rolling in extra cash.
 

N4DJC

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Is anyone hearing any NXDN on NS? I read in a posting a couple of years back that 160.350 was being used.
 
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INDY72

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NS Police are running NXDN with full strapped encryption on both their freqs when they use them, and have noted it once on 160.3500 without encryption on a trip to MS last year. Did not log the RAN. I rarely get to get anywhere near NS trackage. Mostly CSXT, or CN.
 

KG7PBS

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Quite true. With Marine band now narrowbanding internationally, and NXDN being the standard they are looking at... Expect to start seeing Marine NXDN capable radios soon. Also with railroads using NXDN is digital encryption, which is being used on some Police chans, and administrative chans. It will never be used on yard, MOW, or mainline ops, but the days of always being able to hear the rail road cops are coming to an end.
Maybe, I misunderstood the statement due to the break in sentence structure and I wasn't using it against anyone, but I was making a statement that still stands as it will be a long time coming before NXDN is used on mainline channels with "E" or not, and far as NXDN "E" on other channels we use it all the time for Fire Operations and Radio Repair, maybe in about 5 years on MOW and Track too. Still have about 4000 HT-1250's out they, and our PD is soon to be on 800/700 with AES.
Why do Railroad Police need Encryption. What do they need to hide. Hey John CSX502 just killed 2 bums at milepost marker 71.2.
 

INDY72

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They do not want you to know they are busting you for stealing thousands of dollars in retail goods fr that boxcar. Or see you playing with air lines for the braking system which will cause a in yard derail. Or that your planning to actually cause a derail for terrorist reasons?
 

KG7PBS

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They do not want you to know they are busting you for stealing thousands of dollars in retail goods fr that boxcar. Or see you playing with air lines for the braking system which will cause a in yard derail. Or that your planning to actually cause a derail for terrorist reasons?
Ok I can see from your aspect the need for Encryption.
 

otobmark

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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 .

I always figured that the RR's were looking ahead to the 6.25khz mandate looming in the future and wanted to be ready for it if and when it happened. RR are primarily SIMPLEX, and Moto didn't have a simplex 6.25khz solution. Moto has a TDMA 6.25 equivalent solution (DMR and P25 Phase 2) both of which are optimized for repeater operation (trunked only for P25II) and only DMR having TDMA simplex option which does in fact occupy 12.5khz. NXDN is a 6.25khz channel digital format that works better than TDMA in simplex due to among other things no need to execute timing between radios. So, I agree that at the time the decision was made nxdn was indeed the no-brainer.
 
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