11.25 KHz Splits?

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FLRAILMAN

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Hi all, I've been checking the Monitoring Times Fire & Emergency medical service frequency allocation chart & after crosschecking with the FCC database It appears that some of the new 11.25 KHz narrowband frequencies are already assigned to some of the Florida, county & city FD's:

154.0775 MHz Sumter County
154.1825 MHz Lake County
154.1975 MHz Sumter County
154.2125 MHz Putnam County
154.3475 MHz Sumter County
154.3925 MHz Putnam County
154.4075 MHz Lake County
154.4525 MHz Putnam County
154.0025 Mhz Columbia County
155.6175 MHz ?
155.8275 MHz ?
155.8425 MHz ?
155.5875 MHz ?
158.7375 MHz Lake County

Does anybody know if these frequencies are used for voice and/or data transmissions? Thanks in advance.

FLRAILMAN
 

ecps92

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In the VHF high band, where existing 25-kHz (wideband) channels were spaced at 15 kHz, new narrowband channels were created 7.5 kHz from existing channels. The new channels may only be licensed for bandwidths of 12.5 kHz or less.​



Hi all, I've been checking the Monitoring Times Fire & Emergency medical service frequency allocation chart & after

crosschecking with the FCC database It appears that some of the new 11.25 KHz narrowband frequencies are already assigned to some of the Florida, county & city FD's:

154.0775 MHz Sumter County
154.1825 MHz Lake County
154.1975 MHz Sumter County
154.2125 MHz Putnam County
154.3475 MHz Sumter County
154.3925 MHz Putnam County
154.4075 MHz Lake County
154.4525 MHz Putnam County
154.0025 Mhz Columbia County
155.6175 MHz ?
155.8275 MHz ?
155.8425 MHz ?
155.5875 MHz ?
158.7375 MHz Lake County

Does anybody know if these frequencies are used for voice and/or data transmissions? Thanks in advance.

FLRAILMAN
 

Bolt21

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Dec 28, 2005
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Location
Point of Pines
Columbia is using 154.0025 plus 2 others (not on your list) for voice that are already in the RR database. And from looking at the Columbia db, looks like Lake City FD has an NFM freq as well.

I will check the Sumter freqs for activity next time I drive through.
 
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ElroyJetson

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Florida, where you wish you were!
The accepted splits are 25 KHz, 12.5 KHz, and 6.25 KHz. But they are all based on offsets from certain standard freqencies and those offsets may not be consistent across the entire band. This can account for why you think you're looking at an 11.25 KHz split.

Just like in the 2 meter amateur band, there are variations in frequency spacing. Most regions use a 15 KHz channel spacing on 2 meters but Texas and some other states standardized on 20 KHz channel spacing.

Elroy
 
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