Chicago Fire Department 460Mhz. P25

[werinshades]

According to the RR Admin Handbook

Database Administrator Handbook Live Version - The RadioReference Wiki

wiki.radioreference.com

If a particular frequency allocation is used with multiple output tones by a single entity, the frequency shall be entered separately in the database for each tone used.

This is a little different since 1 transmission was P25, and the reply was analog. If someone is depending on the database for programming, by it set up in two different modes will result in missed replies. I self-program, so it's a non-issue for me. @kevino made the notations in the entry. Mixed mode in this situation is not a universal mode used, but each transmission might be different. The "rule" might have to be modified in the event this comes up in the future

ARFF Midway rigs were out drilling this morning, and fortunately I had it programmed CSQ since they were using different modes. The database admins can discuss it amongst yourselves, we reported what we heard.

 

[GTR8000]

This is a little different since 1 transmission was P25, and the reply was analog. If someone is depending on the database for programming, by it set up in two different modes will result in missed replies. I self-program, so it's a non-issue for me. @kevino made the notations in the entry. Mixed mode in this situation is not a universal mode used, but each transmission might be different. The "rule" might have to be modified in the event this comes up in the future

ARFF Midway rigs were out drilling this morning, and fortunately I had it programmed CSQ since they were using different modes. The database admins can discuss it amongst yourselves, we reported what we heard.

Except for the fact that a CSQ listing in the database would be FMN (analog), not P25, so it's a moot point. The rule is clear and @cubn is correct...there needs to be two listings in the RRDB if mixed-mode is in use: one analog listing with the correct PL/DPL, the other the digital listing with the correct NAC (or CC/RAN if applicable).

 

[kevino]

According to the RR Admin Handbook

Database Administrator Handbook Live Version - The RadioReference Wiki

wiki.radioreference.com

If a particular frequency allocation is used with multiple output tones by a single entity, the frequency shall be entered separately in the database for each tone used.

Fixed, separate entries for both analog and P25.

 

[werinshades]

Except for the fact that a CSQ listing in the database would be FMN (analog), not P25, so it's a moot point. The rule is clear and @cubn is correct...there needs to be two listings in the RRDB if mixed-mode is in use: one analog listing with the correct PL/DPL, the other the digital listing with the correct NAC (or CC/RAN if applicable).

No problem for my programming and as I said, it's mainly for those who download from the database.I was thinking aloud here and made a suggestion is all.

 

[GTR8000]

No problem for my programming and as I said, it's mainly for those who download from the database.I was thinking aloud here and made a suggestion is all.

Understood, I was simply pointing out that having the frequency only listed once as FMN/CSQ won't do much good for most scanners models upon importing, as they would assume analog mode once they see CSQ in the tone field. Having two listings per mode is not ideal, but it's better than the scanners expecting analog, then the users would completely miss the P25 transmissions. That's why the rule exists. Well, that and to document both modes being (potentially) active.

 

[werinshades]

Understood, I was simply pointing out that having the frequency only listed once as FMN/CSQ won't do much good for most scanners models upon importing, as they would assume analog mode once they see CSQ in the tone field. Having two listings per mode is not ideal, but it's better than the scanners expecting analog, then the users would completely miss the P25 transmissions. That's why the rule exists. Well, that and to document both modes being (potentially) active.

Understood, and I believe it will all be P25 eventually. Unique programming method I've never encountered before.

 

[ChicagoRadio736]

On a call at O'Hare B gates today CFD was using FG in P25 and Analog like stated about Midway. One unit would tx in digital and another unit would respond in Analog something I can't get used to lol I can hear the P25 in every corner of my house loud and clear. the Analog is broken on the portables but on the rigs I'm good.

 

[west-pac]

I don't know, but yes, they're leaving the UHF-T as I posted previously and using them as a back-up. The city recently renewed a couple license blocks within that range, and I have set up an OFT (One Frequency Trunk) system with all those frequencies in their own site to keep an ear for any testing.

I know this is an old post, but why set up unknown P25 freqs as a P25 channel?... If you're looking to find an unknown frequency in use, or catch traffic on that frequency wouldn't it be easier to set up those freqs as analog channels? At that point you'll be able to hear the digital noise when there is a digital transmission, and then you can fire up your SDR software and get any of the digital parameters that you need.

That's how I find new digital freqs and systems in use.

 

[werinshades]

I know this is an old post, but why set up unknown P25 freqs as a P25 channel?... If you're looking to find an unknown frequency in use, or catch traffic on that frequency wouldn't it be easier to set up those freqs as analog channels? At that point you'll be able to hear the digital noise when there is a digital transmission, and then you can fire up your SDR software and get any of the digital parameters that you need.

That's how I find new digital freqs and systems in use.

Actually, I have it set up as All and hearing both conversations. I'm listening to a disaster drill at Midway currently and can confirm besides Fire ground operating in mixed mode, all simplex frequencies appear to have this capability. Ops 7-10 , Simplex Event channels 1 and 2 all operating in mixed mode NAC 293 and in use.

 

[west-pac]

Actually, I have it set up as All and hearing both conversations. I'm listening to a disaster drill at Midway currently and can confirm besides Fire ground operating in mixed mode, all simplex frequencies appear to have this capability. Ops 7-10 , Simplex Event channels 1 and 2 all operating in mixed mode NAC 293 and in use.

They had full-scale exercise at KFWA a week or two ago. I wonder if it's a traveling NTSB/FAA/DHS crew that's overseeing these exercises; and I wonder where the next one will be next weekend.

 

[werinshades]

They had full-scale exercise at KFWA a week or two ago. I wonder if it's a traveling NTSB/FAA/DHS crew that's overseeing these exercises; and I wonder where the next one will be next weekend.

FAA requires it every 3 years.

 

[INDY72]

Does OEM and CFD do yearly MCI drills with the hospitals like a lot of other cities? And do they have a set in stone date for final transition to full digital UHF?

 

[werinshades]

Does OEM and CFD do yearly MCI drills with the hospitals like a lot of other cities? And do they have a set in stone date for final transition to full digital UHF?

Yes on the drills, unknown if/when UHF transition.

 

[werinshades]

I'm listening to a disaster drill at Midway currently and can confirm besides Fire ground operating in mixed mode, all simplex frequencies appear to have this capability. Ops 7-10 , Simplex Event channels 1 and 2 all operating in mixed mode NAC 293 and in use.

In addition, Fire Command simplex also was heard in mixed mode. Special Events 2 is showing as a repeater frequency which is not correct.

I did see a pattern. Anyone who was utilizing either the ORD 800 or MDW 800 Zone was transmitting on P25 an any of the simplex UHF channels. Those on the FD 800 or EMS 800 Zone were transmitting in analog. One of the chiefs arrived, reported to "communications" that he was switching to the MDW 800 zone on his radio. First heard on analog, then started hearing him transmitting in P25. Some of the portables also transmitted in P25 and I suspect for the same reason.

 

[werinshades]

Actually, I have it set up as All and hearing both conversations. I'm listening to a disaster drill at Midway currently and can confirm besides Fire ground operating in mixed mode, all simplex frequencies appear to have this capability. Ops 7-10 , Simplex Event channels 1 and 2 all operating in mixed mode NAC 293 and in use.

In addition, Fire Command simplex also was heard in mixed mode. Special Events 2 is showing as a repeater frequency which is not correct.

I did see a pattern. Anyone who was utilizing either the ORD 800 or MDW 800 Zone was transmitting on P25 an any of the simplex UHF channels. Those on the FD 800 or EMS 800 Zone were transmitting in analog. One of the chiefs arrived, reported to "communications" that he was switching to the MDW 800 zone on his radio. First heard on analog, then started hearing him transmitting in P25. Some of the portables also transmitted in P25 and I suspect for the same reason.

Just to add for anyone downloading these frequencies from the database, they must be edited to Audio Type set to ALL to properly monitor. As we're made aware, the database either downloads them as analog or digital and not "mixed mode" or All as in the scanners. P25 OFT could see the radio ID's of the units transmitting which came in helpful when I was identifying units , but possible to miss part of the conversations if it's a "mixed mode conversation".

 

[ChicagoRadio736]

Any idea if O'Hare is going to conduct a drill anytime soon?

 

[werinshades]

Any idea if O'Hare is going to conduct a drill anytime soon?

They "normally" don't conduct them in the same year.

 

[n9ihx]

Extensive testing going on this morning on Uhf freqs.

 

[Premises2972]

Hearing lots of traffic on CFD EMS Command 462.975 in P25 mode, unsure what they are saying, i don't have a digital scanner

 

[ILjim]

Hearing lots of traffic on CFD EMS Command 462.975 in P25 mode, unsure what they are saying, i don't have a digital scanner

That's the new CFD Citywide. Getting a NAC of 069.