Wilson County (TN) VHF P25 Conventional upgrades

jpryor

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Wilson County (TN) VHF P25 Conventional upgrades are being prepared for the remaining WEMA and WCSO agencies. The Comm Tech Radio folks have been getting the infrastructure and repeaters ready in the recent months. With Wilson County procuring P25 capable radios over the recent years, some final flashing and reprogramming is what remains for the full switch.

The WEMA Bravo, Charlie and Delta repeaters will go P25, with WEMA Alpha remaining analog for fire dispatch alert tones for the time being. The Wilson Sheriff repeater channels 1, 2 and 3 also expected to go P25. This will put the majority of remaining public safety communications in Wilson County on P25.

The VHF Countywide repeater was the first to have been updated and submitted as running mixed mode with NAC 105.

Other WEMA and WCSO repeaters also mixed mode capability now and with some initial testing, look like remaining NACs will be:

WEMA
Alpha - will remain analog for now
Bravo - NAC 102
Charlie - NAC 103
Delta - NAC 104

Countywide - NAC 105

WCSO
Channel 1 - NAC 301
Channel 2 - NAC 302
Channel 3 - NAC 303

Will continue to submit updates to the RR DB as these details are confirmed and users go live with P25. There are also specific talk group IDs being used as well, even though this is P25 conventional.

The Wilson County VHF P25 repeater system is an upgrade of the existing six site conventional simulcast system, with repeater sites at:
Mt Defiance
Taylorsville Road
Boxwell
Franklin Road
Sheriff's Office / Jail
South Green Hill Road

Other VHF repeaters active, from South Green Hill Road at least, include Mount Juliet Fire (currently analog) and Police links (P25 digital / encrypted). There was mention of keeping and maintaining VHF repeaters and links up for Mount Juliet, and maybe using some City of Lebanon available VHF channels in the future.

WEMA Medics had also switched to 159.1200 MHz P25 NAC 180 (encrypted) for medical reports to TriStar Summit and Vanderbilt Wilson County earlier this year. This is not yet updated in the DB. Odd as the Wilson County EMA outdoor warning sirens continue to send data bursts on this same 159.1200 MHz frequency in analog mode with 110.9 PL, would think this would cause interference.

The existing WEMA and WCSO Digital East and West P25 channels, have seem some selectable encryption in the past. Right now have only seen evidence of P25 clear testing on the upgraded repeaters, would expect some encryption remains available.
 

jpryor

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Wilson County TN WCSO and WEMA switched to full time P25 on their remaining main repeaters this past week. WEMA Alpha is included with NAC 101. All WEMA repeaters are in the clear. WCSO 1 is in the clear, WCSO 2 and 3 are encrypted. Nice TG structure with a unique TG identifier on each conventional repeater and nice Radio ID structure (95xxxxx). Radio identifiers are in use, with the last three digits matching unit number for SO units at least, or assigned unit/apparatus for WEMA.

9500001 Dispatcher
951xxxx WEMA mobiles
952xxxx WEMA portables
953xxxx WCSO mobiles
954xxxx WCSO portables
957xxxx Watertown PD
 

W4EMS

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Jeff,
Sounds like a reasonable approach on SO side. They do need enc capability for various situations including SWAT situations.
That said if they keep the majority clear on F1 that is a reasonable compromise.
 

CORN

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Man I don’t like advancement in technology lol. When SO and Wema were analog I couldn’t hear them from my location in Davidson Co but now only SO has come in since I’ve updated per your post (thx by the way). Doesn’t seem like the SO talks a whole lot but prob P25 vs my location.
 

kchaney56

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Wilson County TN WCSO and WEMA switched to full time P25 on their remaining main repeaters this past week. WEMA Alpha is included with NAC 101. All WEMA repeaters are in the clear. WCSO 1 is in the clear, WCSO 2 and 3 are encrypted. Nice TG structure with a unique TG identifier on each conventional repeater and nice Radio ID structure (95xxxxx). Radio identifiers are in use, with the last three digits matching unit number for SO units at least, or assigned unit/apparatus for WEMA.

9500001 Dispatcher
951xxxx WEMA mobiles
952xxxx WEMA portables
953xxxx WCSO mobiles
954xxxx WCSO portables
957xxxx Watertown PD
I am new to this, I assume that P25 is different them DMR? Are there different versions of P25 and if there are what are the options? I hope that last question is easy to answer. Thanks
 

kchaney56

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Yes, they are completely different.

The simple answer is Phase 1 and Phase 2. I'm not sure what you mean by "options", unless you mean P1 is FDMA and P2 is TDMA.
Yes, they are completely different.

The simple answer is Phase 1 and Phase 2. I'm not sure what you mean by "options", unless you mean P1 is FDMA and P2 is TDMA.
So it looks the two version are FDMA and TDMA, do most radios do both?
 

ki4hyf

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So it looks the two version are FDMA and TDMA, do most radios do both?
TACN (in my area) uses almost a 50/50 split between Phase 1 and Phase 2 traffic, of which probably 90% is unencrypted. There are several commercial scanners available that will receive both Phase 1 and Phase 2. If you feel adventurous, SDR is another option.

On another note, I think we may be on the verge of thread hi-jacking. Perhaps we should start a new thread about P25 and how to listen to it?
 

kchaney56

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TACN (in my area) uses almost a 50/50 split between Phase 1 and Phase 2 traffic, of which probably 90% is unencrypted. There are several commercial scanners available that will receive both Phase 1 and Phase 2. If you feel adventurous, SDR is another option.

On another note, I think we may be on the verge of thread hi-jacking. Perhaps we should start a new thread about P25 and how to listen to it?
Copy that, I am interested in starting a new thread and learning more about P25
 

surfacemount

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TACN (in my area) uses almost a 50/50 split between Phase 1 and Phase 2 traffic, of which probably 90% is unencrypted. There are several commercial scanners available that will receive both Phase 1 and Phase 2. If you feel adventurous, SDR is another option.

On another note, I think we may be on the verge of thread hi-jacking. Perhaps we should start a new thread about P25 and how to listen to it?
TACN wants to migrate completely to Phase II. As long as Phase I radios exist on the system, they can't. The tower will revert to P1 and make all the P2-capable radios dynamically downgrade to P1. The main difference between P1 and P2 is you can load double of the users in the same channel space, which saves TACN from having to add physical tower capacity. Most places don't want to go to P2 because they got their current radios using grant money, and they didn't budget to replace their stuff so quickly (or, in some cases, at all).
P25 is a waveform, like DMR is another kind of waveform, FM Conventional is the waveform you are probably most familiar with.
 

kchaney56

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TACN wants to migrate completely to Phase II. As long as Phase I radios exist on the system, they can't. The tower will revert to P1 and make all the P2-capable radios dynamically downgrade to P1. The main difference between P1 and P2 is you can load double of the users in the same channel space, which saves TACN from having to add physical tower capacity. Most places don't want to go to P2 because they got their current radios using grant money, and they didn't budget to replace their stuff so quickly (or, in some cases, at all).
P25 is a waveform, like DMR is another kind of waveform, FM Conventional is the waveform you are probably most familiar with.
Thank you, this clears it up for me. I have been in South Carolina for a little bit so that is why I am late answering.
 

buddrousa

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@kchaney56
This is not a true statement Phase 1 and Phase 2 Talkgroups can both be active on the same system BUT NOT ON THE SAME TALKGROUP.
If a Phase 1 Radio shows up on a Talkgroup That is Phase 2 then and only then will the Phase 2 radio switch to Phase 1.
The TACN System at this very moment have both Phase 1 and Phase 2 Traffic just not on the samr Talkgroup.
 

kchaney56

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So just to clear things up there are several different types of "Digital Radios" and they do not play with each other; DMR, P25, DStar, Fusion... and it seems that P25 is subdivided into Phase I and Phase II.
 

surfacemount

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Exactly.
They could, because it is mostly software, but they won't because of licensing.

Everything I said is true and correct. TACN wants to go completely phase II. They cannot until all equities are phase II capable. So, exactly like I said, the sites downgrade on a per-call basis when a phase I subscriber unit affiliates. Many older users are completely phase II, so that's ignorant and wrong. And, from the last conversation I had with TACN, yes, you can put a new phase I subscriber unit onto the system, but they don't want to do that, and it would have to be a special circumstance.

But I digress.
 

surfacemount

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TACN wants to migrate completely to Phase II. As long as Phase I radios exist on the system, they can't. The tower will revert to P1 and make all the P2-capable radios dynamically downgrade to P1.

@kchaney56
This is not a true statement Phase 1 and Phase 2 Talkgroups can both be active on the same system BUT NOT ON THE SAME TALKGROUP.
If a Phase 1 Radio shows up on a Talkgroup That is Phase 2 then and only then will the Phase 2 radio switch to Phase 1.
The TACN System at this very moment have both Phase 1 and Phase 2 Traffic just not on the samr Talkgroup.

Reading is fundamental
 
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