Norfolk Southern is licensing NXDN like crazy but I've seen little use of it anywhere. It's like "we're getting ready".... Lately, I see lots of locations in North Carolina getting updated
You've hit it right on the head: "we're getting ready".
NS has one hell of a lot of radio and electronic equipment.
PTC, Microwave links, EOTs, FREDs, thousands HTs, Loco radios, etc.
And this is just the electronics stuff that emits RF!
AAR Technical Services, (the Frequency coordinator for US Railroad frequencies), states on its website:
"However, the FCC has stated that narrowband is just an intermediate step to VERY narrowband but has not set a date yet when that will be required. The AAR recommends that all new radios purchased be very narrowband (NXDN) compatible."
The NS and other railroads are doing the same that they did when Narrow Band was mandated.
Just updating their remote radio sites, installing new equipment, etc, in anticipation of the FCC and AAR mandate is a massive job, and this has to be done while still maintaining all the RF gear and systems already in place.
The NS radio techs installed new equipment while the old system was still in use.
When they had all the new equipment installed, tested, and ready to go, all over the NS, they set a date for each division to switch over to using the new Narrow Band system.
As each division was switched over they had lots of extra radio techs in the area, just in case there was a problem.
After each division was up and running smoothly, another division was switched over, eventually the whole of the NS was switched to narrow band in a few months, after years of preparation.
Remember, AAR sets compatibility standards for all kinds of RR equipment, not just radios.
RR equipment has to be compatible all over North America, so
Consequently ARR Tech Services is mandating NXDN as the next AAR Very Narrow Band emission type radio standard.
NXDN is being handled the same way as the wide band to narrow band change over.
Lots of time being spent preparing for the change over, installing, and testing new equipment; and then a comparatively short actual change over period.
Given the massive amount of equipment that needs to be installed, tested, and issued to operating personnel, while maintaining current equipment, 10 years may not be enough time.
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