Railroad vhf freq's vs other vhf

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cdavisjr

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why is it I'm being told from people in my area as I update my scanner info that most agencies around me that use high band can just switch their emission designator and really don't have to change frequencies to be narrowband compliant but the railroads look like they are changing frequencies altogether to be narrowband...is that a move the industry desired to do anyways?
 

K9WG

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Some agencies don't have to change frequencies as their assigned frequency already falls into the narrow band plan. They do however have to change the emission (deviation) to the narrow band specification.
 

OpSec

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Some agencies don't have to change frequencies as their assigned frequency already falls into the narrow band plan. They do however have to change the emission (deviation) to the narrow band specification.
No agency has to change the physical frequency(s) they operate on. The change occurs with emission bandwidth being reduced from 5kHz (25kHz channel spacing) to 2.5kHz (12.5kHz channel spacing). All this means is that in theory there will be double the number of channels available for assignment in the spectrum, but in reality this won't be the case because the actual frequencies aren't changing for 99% of the agencies.

The new AAR channel plan for the RR's has the new channel spacing with many more channels than the legacy 25kHz channel plan allowed for. The industry as a whole is much better suited to make such a change than hundreds of thousands of business pool and public safety pool users.
 

kb2vxa

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"...the railroads look like they are changing frequencies altogether to be narrowband...is that a move the industry desired to do anyways?"

Yes and no. If you want you can stay on the same frequency but to use the new four digit splinter frequencies you have to change frequency or add it to the license.
 

RadioDitch

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No agency has to change the physical frequency(s) they operate on. The change occurs with emission bandwidth being reduced from 5kHz (25kHz channel spacing) to 2.5kHz (12.5kHz channel spacing). All this means is that in theory there will be double the number of channels available for assignment in the spectrum, but in reality this won't be the case because the actual frequencies aren't changing for 99% of the agencies.
The AAR channel plan will change in that there will be new channels added in between the tradtional ones. But like OpSec noted, and straight from the AAR's own mouth, most roads/regions probably won't even utilize the new "between" channels once the 12.5kHz change over is complete anyway.

http://www.dpdproductions.com/page_rrfreqs_newplan.html

The industry's self-imposed change to 6.25kHz NXDN (aka IDAS) digital, if it still happens, in 2018 will be interesting though.
 
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