RR vs FCC database

MGK

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If I compare some of the frequencies for a P25 network with the license listing in the FCC database There are usually more frequencies listed in the FCC database for the license(s) listed. Why would this be?
 

GTR8000

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Provide an example we can look at. Also remember that the FCC licenses for trunked systems usually list the repeater inputs, in addition to the repeater outputs. Only the outputs are listed in the RRDB for trunked systems.
 

n5ims

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There could be several reasons. The most obvious one is the FCC database will list both the input and output frequencies while the RR database defaults to only listing the repeater output frequencies. Many agencies that have or use a large trunking system may have simplex frequencies for various uses (think the water department working in places where repeater use is not possible but the users are close together and still need to communicate).

Other related issues are the P25 network may use frequencies that aren't listed on a license. This is often because the network was built by merging several older networks together that operated under their own license so the new network may operate under multiple licenses.
 

MGK

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How would I know the "the in" from "The out", looking at the FCC database all are showing an output power level
 

GTR8000

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How would I know the "the in" from "The out", looking at the FCC database all are showing an output power level
Oh, and to answer generically. Repeater outputs are FB2 or FB8 for public safety trunking; inputs are either MO or FX1. Most bands like UHF, T-Band, 700, 800, 900 have standard offsets. T-Band, for example, the input is +3 MHz. 700 is +30 MHz. 800 is -45 MHz. VHF is a crapshoot.
 

Whiskey3JMC

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Sometimes a trunked system license will include frequencies for conventional use that are not part of the trunked system.
I know of certain radio vendors for Part 90.35 eligible lessees who are licensed as radio service "YG" (business trunked) and use their frequencies conventionally. It's always fun to try and identify the subscribers. Mostly student transportation, private ambulances, taxi cabs, even have a cemetery headstone crew in my area. Very little radio etiquette or professionalism on these freqs :)
 

wa8pyr

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If I compare some of the frequencies for a P25 network with the license listing in the FCC database There are usually more frequencies listed in the FCC database for the license(s) listed. Why would this be?
In addition to frequencies not used on the trunked system, most likely you're seeing the same frequencies multiple times; the FCC license shows not only an entry for each frequency at each location, but also for each frequency and modulation per location. So if a system has five frequencies at three locations as well as both analog and digital emissions, you could easily see the same five frequencies listed 30 times (each analog frequency at each location totals fifteen and each digital frequency at each location, fifteen more).

Sometimes a trunked system license will include frequencies for conventional use that are not part of the trunked system.
Don't think I've ever seen conventional and trunked frequencies on the same license as they're two different services (at least for public safety); trunked usually has a service code such as YE while conventional usually has a service code such as GE. It is not uncommon for agencies to utilize frequencies on a trunked license in conventional mode if they don't need them for the trunked system (so they don't lose them).
 

GTR8000

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In addition to frequencies not used on the trunked system, most likely you're seeing the same frequencies multiple times; the FCC license shows not only an entry for each frequency at each location, but also for each frequency and modulation per location. So if a system has five frequencies at three locations as well as both analog and digital emissions, you could easily see the same five frequencies listed 30 times (each analog frequency at each location totals fifteen and each digital frequency at each location, fifteen more).
That may be true of the RR interpretation of the FCC database, however it's not the case in the ULS. Each frequency is listed once per location, not one entry per licensed emission. There is a link to display the emissions for each frequency.

Don't think I've ever seen conventional and trunked frequencies on the same license as they're two different services (at least for public safety); trunked usually has a service code such as YE while conventional usually has a service code such as GE. It is not uncommon for agencies to utilize frequencies on a trunked license in conventional mode if they don't need them for the trunked system (so they don't lose them).
I've seen numerous instances where FB stations are licensed under a trunking license, vs the expected FB2, FB8, etc. for system repeaters. And of course there are many examples of where frequencies from non-trunked licenses are being used as part of trunked systems.
 

nd5y

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Don't think I've ever seen conventional and trunked frequencies on the same license as they're two different services (at least for public safety); trunked usually has a service code such as YE while conventional usually has a service code such as GE. It is not uncommon for agencies to utilize frequencies on a trunked license in conventional mode if they don't need them for the trunked system (so they don't lose them).
I have seen a lot of public safety trunked systems with conventional interop repeaters and mobile simplex talkaround/tactical frequencies on the same license with trunked service codes. Here are just two.
Location 9 (mobile) the last two frequencies 853.35 and 853.7 are simplex channels and also has 8CALL90D-8TAC94D and mobiles licensed on each repeater output.
Several locations have 8CALL90-8TAC94 conventional repeaters.
 
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