New 800MHz Interop in Butler County

Drachen_Fire

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Playing with a new system radio this morning, and made a discovery. There are two NPSPAC repeaters on the air that were not previously there. One on 8CALL90, and another on 8TAC91. Both were able to be reached from Butler Commons, on an APX4000 portable. The new radios are apparently set up so that the standard 8CALL/8TAC channels are analog, on a repeater split, while the 8CALLD/8TACD channels are simplex digital. Still no idea on NAC for simplex or PL for repeaters, but they are certainly there, loud and clear.
 

ecps92

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The "D" represents Direct aka Simplex, not Digital
See Page 51 - https://www.dhs.gov/sites/default/files/publications/nifog_ver_1.6.1a_final_01-22-19_0.pdf

Playing with a new system radio this morning, and made a discovery. There are two NPSPAC repeaters on the air that were not previously there. One on 8CALL90, and another on 8TAC91. Both were able to be reached from Butler Commons, on an APX4000 portable. The new radios are apparently set up so that the standard 8CALL/8TAC channels are analog, on a repeater split, while the 8CALLD/8TACD channels are simplex digital. Still no idea on NAC for simplex or PL for repeaters, but they are certainly there, loud and clear.
 

Drachen_Fire

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It's confusing, really. I have read documents from FEMA some time back that said that VTAC/UTAC/8TAC could be programmed as analog 156.7 or digital $293, although I haven't seen that document in about 5 or 6 years, and everything else I see says to use them as analog.

Another thing, it seems. The P25 simplex programming does not appear to use $293 as the NAC. I'll reprogram here in a little bit as A/D search, and see what the NAC is for digital, and possibly what the PL is for analog.

We have a bunch of the 7CALL/7TAC channels in there, too. I'm hoping those are $293.
 

Drachen_Fire

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This is the strangest thing I've seen so far.

Portable-to-portable, APX-to-APX, those 8CALL/8TAC simplex channels sound digital. Highly clear audio. Sounds like digital modulation.

But it's not. It's analog narrow (?). No idea why, as I thought 800MHz was largely wideband in conventional mode. It's programmed for 156.7Hz TPL on all repeater and simplex.

Still, there are now repeaters accessible from central/south-central Butler County on 8CALL90 and 8TAC91 that I've never heard there before.
 

GTR8000

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800 MHz analog should be 4 kHz/20 kHz TX/RX deviation. Not quite full wideband (5/25 kHz), but certainly not narrowband (2.5/12.5 kHz).

Of course P25 modulation is always 2.5/12.5 regardless of band.
 

Drachen_Fire

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I'm still super-confused at the APX audio quality on analog. Did they add some kind of high-end signal processing or speech clarification feature? Short range portable-to-portable, it sounds ridiculously clear, and has a slight vocoded ring to it like P25 audio.
 

GTR8000

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All audio, both analog and digital, goes through the radio's DSP. While analog audio is obviously not vocoded, it's still subject to processing by the DSP, including noise removal. There are myriad of audio settings in the APX that could affect the way both the TX and RX audio sound.
 

Drachen_Fire

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I've not even seen the CPS side of the APX series yet. The most recent Motorola stuff I've worked with is XPR and XTS/XTL series. These are really nice radios. Tested out against known analog again, and it sounds too nice to be analog. Incredible.
 

ecps92

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Contact your SWIC who should be aware of where those IO sites are.
Many agencies keep them DOWN, until asked to turn them on, maybe someone forgot to disable them

This is the strangest thing I've seen so far.

Portable-to-portable, APX-to-APX, those 8CALL/8TAC simplex channels sound digital. Highly clear audio. Sounds like digital modulation.

But it's not. It's analog narrow (?). No idea why, as I thought 800MHz was largely wideband in conventional mode. It's programmed for 156.7Hz TPL on all repeater and simplex.

Still, there are now repeaters accessible from central/south-central Butler County on 8CALL90 and 8TAC91 that I've never heard there before.
 

Drachen_Fire

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Not really sure why that's a common thing for the 8CALL channel set. It doesn't make a lot of sense to me to switch repeaters off, especially ones used for interop. In PA, we have a whole bunch of UHF UCALL/UTAC repeaters that are linked into the State trunk, and they're on all the time.
 

ecps92

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All depends on how a state and neighboring states want to handle it.
some find it easier to go with a "Mother May I use, and can you enable" vs un-coordinated chaos of multiple repeaters being tripped because one person is at enough elevation to hit 3-5 repeaters at the same time...
Not really sure why that's a common thing for the 8CALL channel set. It doesn't make a lot of sense to me to switch repeaters off, especially ones used for interop. In PA, we have a whole bunch of UHF UCALL/UTAC repeaters that are linked into the State trunk, and they're on all the time.
 

maus92

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The 700 mhz national interop channels are P25 and 293 NAC; the 800 interops are 156.7 and FMN.

I also noticed that Butler hasn't licensed the 800 interops, which I believe they are required to do - at least our county does.
 
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GTR8000

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the 800 interops are 156.7 and FMN.
The 800 MHz nationwide interop frequencies are programmed wideband 4.0/20.0 kHz deviation, not narrowband 2.5/12.5 kHz.

Directly out of the NIFOG guide:

76835
 

maus92

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ecps92

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All depends on how the SWIC and state agency the SWIC works for wants to handle these

Some states hold the License vs having individual agencies, counties get the license.

Best to find out how PA handles this, thru the SWIC

The 700 mhz national interop channels are P25 and 293 NAC; the 800 interops are 156.7 and FMN.

I also noticed that Butler hasn't licensed the 800 interops, which I believe they are required to do - at least our county does.
 

maus92

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I'm still looking through the rules, but came across this in the NIFOG that may explain a lack of license:

"2. For FCC licensees, the non-Federal National Interoperability Channels VCALL10-VTAC14 and VTAC33-38, UCALL40-UTAC43D, the 800 MHz interoperability channels, and 8C A L L90-8TAC94D are covered by a “blanket authorization” from the FCC - “Public safety licensees ... can operate mobile units on these interoperability channels without an individual license.” See FCC 00-348, paragraph 90 (released October 10, 2000) for VHF and UHF; see FCC rules 90.421(a)(3) and 90.525(a) for 700 MHz; see FCC 87-112, paragraph 34 (released December 18, 1987), for 800 MHz. When North of Line A or East of Line C the blanket authorization in paragraph 90 of FCC 00-348 applies only to mobile (including hand-held) stations operating with an effective radiated power (ERP) of 3 watts or less. At higher power levels, frequency coordination is required."

"3. You may operate on frequencies authorized to another licensee when that licensee designates you as a unit of their system, in accordance with FCC rule 90.421; or as an authorized user of a shared radio system pursuant to a written agreement as described in FCC rule 90.179."

And in an IMMEDIATE [their emphasis] emergency situation, a part 90 licensee can operate on these frequencies.

Our county was initially issued a STA, then a permanent license after going through a frequency coordination process with RPC 20. Maybe because we also use fixed repeater sites at high power (>3 watts?) IDK. The state EMA coordinates the use of the repeater sites, activating them as required.

As for the discrepancy between the apparently mandated 20K0F3E emission designator and our county's licensed 14K0F3E, doing a search shows most current subscribers do not support 20K0F3E, but do support 14K0F3E in their radios. One Harris radio spec I reviewed stated "14K0F3E @ 20K."

Should the RRDB listing for the 800 interop channels be changed to FM from NFM?
 
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ecps92

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Basically - Simplex or using someone elses Repeater your Part 90 license covers you under the NIFOG or State License
Installing a Repeater or Base - you need to Apply [contact the SWIC for the policy in your state] for a License

I'm still looking through the rules, but came across this in the NIFOG that may explain a lack of license:

"2. For FCC licensees, the non-Federal National Interoperability Channels VCALL10-VTAC14 and VTAC33-38, UCALL40-UTAC43D, the 800 MHz interoperability channels, and 8C A L L90-8TAC94D are covered by a “blanket authorization” from the FCC - “Public safety licensees ... can operate mobile units on these interoperability channels without an individual license.” See FCC 00-348, paragraph 90 (released October 10, 2000) for VHF and UHF; see FCC rules 90.421(a)(3) and 90.525(a) for 700 MHz; see FCC 87-112, paragraph 34 (released December 18, 1987), for 800 MHz. When North of Line A or East of Line C the blanket authorization in paragraph 90 of FCC 00-348 applies only to mobile (including hand-held) stations operating with an effective radiated power (ERP) of 3 watts or less. At higher power levels, frequency coordination is required."

"3. You may operate on frequencies authorized to another licensee when that licensee designates you as a unit of their system, in accordance with FCC rule 90.421; or as an authorized user of a shared radio system pursuant to a written agreement as described in FCC rule 90.179."

And in an IMMEDIATE [their emphasis] emergency situation, a part 90 licensee can operate on these frequencies.

Our county was initially issued a STA, then a permanent license after going through a frequency coordination process with RPC 20. Maybe because we also use fixed repeater sites at high power (>3 watts?) IDK. The state EMA coordinates the use of the repeater sites, activating them as required.

As for the discrepancy between the apparently mandated 20K0F3E emission designator and our county's licensed 14K0F3E, doing a search shows most current subscribers do not support 20K0F3E, but do support 14K0F3E in their radios. One Harris radio spec I reviewed stated "14K0F3E @ 20K."

Should the RRDB listing for the 800 interop channels be changed to FM from NFM?
 
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