NFM Vs. WFM Vs. FM Questions, Please

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BOBRR

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Hello,

Some questions re NFM vs FM, vs WFM, please:

a. I believe that Police, Fire, Railroads, and "Public Service" now are all on NFM.
True ?

b. But what about Maritime, such as for the C.G. ? Fishing and pleasure boats, etc. the same ?

c. What about Commercial Air ? (do they use any fm at all ?)

d. What about MIL Air ?

Thanks,
Bob
 

nd5y

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Marine band is FM. It was not subject to narrowbanding.
The VHF civil aircraft band (108-137) is AM.
The VHF military bands (138-144, 148-150.75) have a mixture of AM aircraft and NFM or digital land mobile radio.
The UHF military aircraftt band (225-400) is mainly AM but there are some satellite channels that use WFM or digital modes.
The 380-400 band is mostly military land mobile using digital or NFM but there are a few AM aircraft frequencies.
 

prcguy

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To take the previous answer further, most all public service and commercial VHF/UHF has gone "narrow band" as of Jan 2013 and what this means is they went from +/- 5KHz deviation to +/- 2.5KHz deviation, which has a minor effect when receiving on a typical police scanner which are usually designed for up to +/- 8KHz in NFM mode.

Some scanners and ham radios have a WFM setting which is usually much wider like +/- 75KHz for commercial FM broadcast (music) and older analog TV audio that was +/- 25KHz deviation. Listening to public service in this mode will not work so good as the audio will be very low and you can pick up several channels at the same time.

So if your question was relating to NFM and WFM settings on a scanner, public service and commercial stuff has always been NFM and will continue to be.

VHF marine was not included in the recent narrow band mandate and still operates a +/- 5KHz deviation but will use the NFM mode on a scanner.
prcguy
 

ka3jjz

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Moved since this discussion has nothing to do with services below 30 Mhz. Carry on, gentlefolks...Mike
 

KB7MIB

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Wirelessly posted (Opera/9.80 (BREW; Opera Mini/6.0.3/27.2354; U; en) Presto/2.8.119 320X240 LG VN530)

What about 800 MHz? I read somewhere (here, maybe?) they were not subject to the narrowband mandate.
Digital users went NFM as digital is narrow to start with, but the analog users were allowed to remain FM. But then I wonder about the Motorola mixed-mode Type IIi systems, which use both analog and digital talkgroups. Should the system be set to NFM or FM? I currently use NFM on my PSR-500.
 
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