The Failed NS P25 Experiment

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BigLebowski

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Some interesting historical information... The below template is from an NS XTS3000 that was being used to test P25 in Atlanta(?) before NXDN was ultimately chosen. Not sure I agree with their setup or understanding of how P25 worked, but interesting nonetheless. I can't help but think if the techs understood how P25 worked a little better rather than trying to place multiple users on the same voice frequency with different talkgroups, AAR might have gone a different direction.

ChannelAliasReceive FrequencyTransmit FrequencyNAC/Talkgroup
1TR CY 1161.535160.665303 / TG 2
2TR YARD161.490161.490303 / TG 7
3TR HUMP161.490160.770303 / TG 8
4TR CY 2161.490161.490303 / TG 6
5TR LOC161.250161.250303 / TG 10
6ME CAR161.295160.365303 / TG 1
7ME LOCO161.295160.365303 / TG 3
8ME MECH161.295160.365303 / TG 2
9C&S161.295160.365303 / TG 4
10M / W161.295160.365303 / TG 5
11YD16160.320160.740CSQ Analog
12UNPROG
13UNPROG
14UNPROG
15UNPROG
16HAILING160.320160.320CSQ Analog
 

tunnelmot

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Not only multiple simplex talkgroups on one frequency, but channels 2,3 and 4 are simplex/repeater mixed:oops:
Looks like a mess.
 

RRR

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You can still do pretty much the same with NXDN, put in Talkgroups just like above. Substitute the RAN for the NAC. I doubt the programming above made any difference in the choice of NXDN V/S P25.
 

BigLebowski

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You can still do pretty much the same with NXDN, put in Talkgroups just like above. Substitute the RAN for the NAC. I doubt the programming above made any difference in the choice of NXDN V/S P25.

Just because you can doesn't mean you should. Just shows how well they understood what they were doing.
 
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BigLebowski

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NS had digital briefly in Birmingham. What a mess.

This may very well have been Birmingham, there were several zones in the radio but I am not familiar with the area to know what is or was in use.
 

RRR

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NS has "Digital" all over the place, in the form of NXDN/IDAS.

Just because you aren't aware, or know where to look, doesn't mean it isn't out there.
 
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Yea the whole point of my comment is that they're not going to spend it all willy nilly like public safety does on multi thousand dollar portables. Anybody that knows corporate knows the nickle and dimeing that goes on regarding expenses for employee equipment, they'd rather not if they could. If we did, every RR employee would be sporting Moto APXs
 

burner50

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Yea the whole point of my comment is that they're not going to spend it all willy nilly like public safety does on multi thousand dollar portables. Anybody that knows corporate knows the nickle and dimeing that goes on regarding expenses for employee equipment, they'd rather not if they could. If we did, every RR employee would be sporting Moto APXs

No... You've gotten it all wrong...

The railroad industry chose over a decade ago that P25 was not their digital radio emission... So, no... Every RR employee would *NOT* be sporting APX's... However, almost every RR employee has been sporting commercial NXDN portables for about 15 years and locomotives have had clean cab radios capable of NXDN for about ten years.

And, having worked for a Class 1 for ten years, I can attest that they do indeed spend money all willy nilly. Public Safety has multi thousand dollar portables because they have "mission critical" communication needs... The railroad does not. If a radio fails, the train just operates on signals or stops. Corporate "nickle and dimeing" isn't realized on the railroad. They'll make a mistake that costs as much as a statewide P25 trunked radio network and not even bat an eye.
 
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