Luzerne County P25

[One13Truck]

Edit. Apparently I remembered to set the record on my 100. Looks like it was coming over on TG 1025. I’m holding off on submitting that since it only happened for a few hours on the 24th and I haven’t heard it since. But if anyone wants to keep an ear open for it to pop up again and it seems confirmed we might be able to lock that in.

 

[maus92]

How would you describe the qualities of the audio on tg 1025? Were both sides the same?

 

[W7FDX]

ECEN did the same thing for a few days about a week or two ago. They patched the analog FD dispatch with the P25 FD Dispatch TG (20051) but cut it off only after a few days and haven't heard it since.

I got the talkgroup wrong, it's 20055 not 20051.

 

[One13Truck]

How would you describe the qualities of the audio on tg 1025? Were both sides the same?

I’m probably not the best to ask since I HATE P25 systems. But compared to most P25 systems it wasn’t terrible. Only sounded slightly overblown and robotic/digital and like they were talking with the mic shoved all the way to their uvula. As opposed to most P25 that sounds like the mic is shoved all the way into the lungs. I’d put it around 2-3 or so notches below the OC/Worcester level of how it sounded. If that’s helpful.
The conventional sounds much better though. If they keep it patched in when the new system goes online I’ll be keeping the conventional as a priority scan rather than listen to the TG.

 

[cpg178]

I’m probably not the best to ask since I HATE P25 systems. But compared to most P25 systems it wasn’t terrible. Only sounded slightly overblown and robotic/digital and like they were talking with the mic shoved all the way to their uvula. As opposed to most P25 that sounds like the mic is shoved all the way into the lungs. I’d put it around 2-3 or so notches below the OC/Worcester level of how it sounded. If that’s helpful.
The conventional sounds much better though. If they keep it patched in when the new system goes online I’ll be keeping the conventional as a priority scan rather than listen to the TG.

Are the tones all distorted and super loud compared to the dispatchers voice like how they are on .450?

 

[One13Truck]

Are the tones all distorted and super loud compared to the dispatchers voice like how they are on .450?

Yep. It pretty much patched over directly. Just with the usual digital sounding blahness P25 excels in.
But I think the change in how the tones sound is from the new consoles so it’s here to stay. I don’t hate the change in how they sound but it has changed just enough to throw me off on who some are. I miss the beep at the end of the tones though. That dropped with the console change. And there seems to be a really long gap of silence before/between tones on the new consoles which sounds strange.

 

[W7FDX]

Yep. It pretty much patched over directly. Just with the usual digital sounding blahness P25 excels in.
But I think the change in how the tones sound is from the new consoles so it’s here to stay. I don’t hate the change in how they sound but it has changed just enough to throw me off on who some are. I miss the beep at the end of the tones though. That dropped with the console change. And there seems to be a really long gap of silence before/between tones on the new consoles which sounds strange.

Not to mention how quiet how the dispatchers voice is compared to the tones.

 

[maus92]

It’s likely those tone groups are simply part of the legacy system which will sound like crap when patched to a digital tg. Is the county moving FTO to a tg, or will they be retaining the current analog channel for this purpose?

 

[IStebleton]

Yep. It pretty much patched over directly. Just with the usual digital sounding blahness P25 excels in.

P25 is probably the best sounding digital mode in my opinion. Have you ever heard DMR?

 

[W7FDX]

P25 is probably the best sounding digital mode in my opinion. Have you ever heard DMR?

I personally think P25 and NXDN sound very similar probably because they both use the AMBE+2 vocoder. But I agree out of the big 3 I'd say P25 and NXDN are tied and DMR comes in last.

 

[GTR8000]

They all use a DVSI vocoder. P25 Phase I (FDMA) uses the older IMBE vocoder. P25 Phase II (TDMA), DMR/MOTOTRBO (also TDMA), and NXDN (FDMA) all use the AMBE+2 vocoder.

 

[One13Truck]

It’s likely those tone groups are simply part of the legacy system which will sound like crap when patched to a digital tg. Is the county moving FTO to a tg, or will they be retaining the current analog channel for this purpose?

The 157.45 will be kept for paging so I’m not sure if this was just a one day test or if they’ll actually have a patch full time once the system goes online.

It sounds that way over analog as well. It changed over the Summer as they cut over to the new consoles. There was a noticeable difference in how it sounds on the new vs the old as they were half and half on the old and phasing in the new. The new consoles have been in use for a few months now so I’m guessing it’s the new equipment rather than the patching.

 

[W7FDX]

They all use a DVSI vocoder. P25 Phase I (FDMA) uses the older IMBE vocoder. P25 Phase II (TDMA), DMR/MOTOTRBO (also TDMA), and NXDN (FDMA) all use the AMBE+2 vocoder.

Thank you for reminding me, I forgot DMR used the AMBE+2 vocoder as well. But as far as voice quality goes I much prefer P25 or NXDN over DMR but that's just my opinion.

 

[cpg178]

The 157.45 will be kept for paging so I’m not sure if this was just a one day test or if they’ll actually have a patch full time once the system goes online.

It sounds that way over analog as well. It changed over the Summer as they cut over to the new consoles. There was a noticeable difference in how it sounds on the new vs the old as they were half and half on the old and phasing in the new. The new consoles have been in use for a few months now so I’m guessing it’s the new equipment rather than the patching.

I dont know if it has anything to do with 157.450 being a 25khz paging channel as opposed to all other counties having 12.5khz, but if you compare Luzerne to say Lackawanna the tones sound horrendous. I mean at the end of the day it doesnt really matter how they sound as long as they decode properly on the equipment that is needed to be alerted. But I am still curious as to why.

 

[maus92]

There is an adjacent jurisdiction to us that uses it legacy VHF paging channel for FTO, but uses a P25 channel for voice dispatch. They elected to include the tone pairs in the dispatch audio stream that goes out over the Phase 2 tg, and it sounds bad. Our county simulcasts the dispatch voice over VHF and an 800 tg, but the tones are only sent on the analog VHF channel.

 

[W7FDX]

I dont know if it has anything to do with 157.450 being a 25khz paging channel as opposed to all other counties having 12.5khz, but if you compare Luzerne to say Lackawanna the tones sound horrendous. I mean at the end of the day it doesnt really matter how they sound as long as they decode properly on the equipment that is needed to be alerted. But I am still curious as to why.

How were they able to keep their paging channel at 25khz with the narrowband mandate?

 

[GTR8000]

How were they able to keep their paging channel at 25khz with the narrowband mandate?

157.450 is exempt from the narrowband mandate.

 

[smorris]

Thank you for reminding me, I forgot DMR used the AMBE+2 vocoder as well. But as far as voice quality goes I much prefer P25 or NXDN over DMR but that's just my opinion.

It’s not just your opinion.

 

[cpg178]

Looking at my radio programming, I never got the 25khz EID for my XPR5550s so the fact that I have a 25khz channel programmed as 12khz is probably making them sound even worse. Need to get around to getting the EID one of these days. When they finally bring the system online if the audio quality of the digital TG is better I will just monitor that instead,

 

[One13Truck]

The 157.45 is back to being patched onto TG 1025 this afternoon. If it seems to be an official thing or at least semi-permanent over the next day or three I’ll get it submitted.