Goosetown/Triangle Communications Tier 3 System

[GTR8000]

To reiterate for the sake of clarity...

• For UHF range 450.0000 - 469.9875: Use 450.0000 as the base frequency, which is LCN 1 (LSN 3/4), in 12.5 kHz steps
• For T-Band range 470.0000 - 512.0000: Use 454.3375 as the base frequency, which is LCN 1 (LSN 3/4), in 12.5 kHz steps

Or if you prefer you can also use 470.0000 as the base frequency for the T-Band range, which would start you off at LCN 1254 (LSN 2509/2510)

 

[pro92b]

Site 114 added a frequency. Reception is difficult here and traffic sparse so I have not heard voice traffic on the new frequency yet, just logged it on the control channel.

 

[cg]

Haven't been paying much attention to the Goosetown stuff recently but I noticed I was not getting a signal from the Bloomfield CT site. However, I am getting a signal on one of the Con+ frequencies from Farmington CT that has been changed to the Tier III.

L5-101 (L6-13.6) Farmington CT (Rattlesnake Mtn)
454.23125 (channel 2439)
DCC 10
No voice channels yet
Neighbors:
L5-104 (L6-14.1) no longer receiving signal, had been very strong, still showing as neighbor
L5-112 (L6-15.1)
L5-131 (L6-17.3)
L5-151 (L6-19.8)

I also get site L5-151 (L6-19.8) on 452.4625. I am guessing it is either Glastonbury CT or more likely, Holyoke MA (Mt Tom). I can't track down a license that might fit that frequency to confirm. Signal strength seems similar to Holyoke CON+ site from my location in North Central CT. It is not a NY site as I would never receive that here.
L5-151 (L6-19.8)
452.46250 (channel 397)
DCC 10
No Voice channels yet
Neighbors:
L5-101 (L6-13.6) Farmington CT (Rattlesnake Mtn)
L5-132 (L6-17.4)
L5-151 (L6-19.8) it shows itself as a neighbor

 

[GTR8000]

Site 101 is Hartford, Site 151 is Mount Tom.

PS - 17.3 = 130 (not 131) and 17.4 = 131 (not 132)

 

[GTR8000]

To reiterate for the sake of clarity...

• For UHF range 450.0000 - 469.9875: Use 450.0000 as the base frequency, which is LCN 1 (LSN 3/4), in 12.5 kHz steps
• For T-Band range 470.0000 - 512.0000: Use 454.3375 as the base frequency, which is LCN 1 (LSN 3/4), in 12.5 kHz steps

Or if you prefer you can also use 470.0000 as the base frequency for the T-Band range, which would start you off at LCN 1254 (LSN 2509/2510)

Add a new wrinkle...the 454 MHz frequencies that have five digits after the decimal point ending with a 5 (e.g. 454.16875, 454.23125, etc.)

• Use 439.00625 as the base frequency, which is LCN 1 (LSN 3/4), in 12.5 kHz steps

 

[DaveNF2G]

Why not a base frequency in 6.25 kHz steps?

 

[GTR8000]

Why not a base frequency in 6.25 kHz steps?

Because the channels in that range are spaced no less than 12.5 kHz apart. DMR does not fit within a 6.25 kHz channel space, so it wouldn't make sense to use a band plan based on 6.25 kHz steps.

 

[seagravebuff60]

L5-101 (L6-13.6) Farmington CT (Rattlesnake Mtn)
454.23125 (channel 2439)
DCC 10
No voice channels yet

L5-151 (L6-19.8)
452.46250 (channel 397)
DCC 10
No Voice channels yet

For sites with only one frequency in use, one slot acts as the CC slot, and the other acts as the voice slot.

 

[GTR8000]

For sites with only one frequency in use, one slot acts as the CC slot, and the other acts as the voice slot.

Ah, the beauty of DMR/TDMA control channels lol

 

[DaveNF2G]

Because the channels in that range are spaced no less than 12.5 kHz apart. DMR does not fit within a 6.25 kHz channel space, so it wouldn't make sense to use a band plan based on 6.25 kHz steps.

Actually, they are spaced at 6.25 kHz in the Part 22 ranges. Using that spacing throughout the entire band would enable use of a single bandplan instead of two interlaced bandplans.

I understand, of course, that the existing equipment is not programmed that way, so this proposed bandplan modification would only be useful for SDR experimentation, and would produce a lot of "wrong" channel numbers when run against the current systems.

 

[GTR8000]

Actually, they are spaced at 6.25 kHz in the Part 22 ranges.

Actually, they are not.

The Part 22 UHF licenses are allocated in 25 kHz channel blocks that have specific channel block designations, and per Part 22 Subpart E §22.561 the bandwidth is 20 kHz on center frequency.

Channel Block ID​	Channel Block MHz​	Center Frequency​
GA	454.0125 - 454.0375	454.025
GB	454.0375 - 454.0625	454.050
...
GY	454.6125 - 454.6375	454.625
GZ	454.6375 - 454.6625	454.650

 

[DaveNF2G]

So why are there so many channels with 5 digits after the decimal?

 

[GTR8000]

So why are there so many channels with 5 digits after the decimal?

Because that's how the radio shops decided to slice and dice them up, in order to maximize the amount of channels they can squeeze out of each block.

Channel Block GA spans 454.0125 - 454.0375 with a center frequency of 454.025 as noted above. That's 25 kHz of bandwidth. Guess how much bandwidth DMR occupies? 12.5 kHz. So if you create two new center frequencies within that 25 kHz of spectrum, you wind up with 454.01875 and 454.03125, 12.5 kHz of bandwidth each fitting within that 25 kHz block.

You may need to enable '6.25 kHz stepping' in your scanner or FMPx in order to land on one of those frequencies with 5 digits after the decimal point, but that is not the same as "they are spaced at 6.25 kHz in the Part 22 ranges", nor does it mean that the Tier III band plan is using 6.25 kHz steps. It's not, the band plan is as I stated above using 12.5 kHz steps, because that is the bandwidth of the DMR channels.

 

[DaveNF2G]

Why does channel center spacing have to be locked to signal bandwidth? Theoretically, I mean. I understand that the established bandplans are constructed that way, but it seems intuitive that they should be handled as separate parameters because they serve different purposes.

 

[GTR8000]

We're straying off topic now. I'd suggest asking your question in a new thread in the proper forum for that sort of discussion.

 

[GTR8000]

Those running the latest DSD+ Fast Lane 2.457 (released 12/27/2023), you'll need to set this system up as TIIInonStd. Here are some examples of how each file might be setup for the system. If you wish to retain existing Groups and Users coming from a previous Fast Lane release, you'll need to modify the lines to change from TIII to TIIInonStd, as well as change the NetID from 5 to L5. If you had this system setup as NetID 6 with all the x.xx site numbering, you'll need to fix all of that to comply with the latest release of Fast Lane. Details are in the 2.457 release notes.

Note that these examples only include the Goosetown sites; use this as a template for those monitoring the Triangle sites.

DSDPlus.networks
TIIInonStd,L5,"OneVoice MAX"

DSDPlus.sites
; OneVoice MAX
TIIInonStd,L5,101,"Hartford"
TIIInonStd,L5,104,"Bloomfield"
TIIInonStd,L5,111,"Pomona"
TIIInonStd,L5,112,"Valhalla"
TIIInonStd,L5,114,"Beacon"
TIIInonStd,L5,121,"Schunnemunk"
TIIInonStd,L5,130,"Putnam Valley"
TIIInonStd,L5,131,"Woodstock"
TIIInonStd,L5,134,"Esopus"
TIIInonStd,L5,151,"Mt Tom"

DSDPlus.siteLoader
TIIInonStd,L5,0,"OneVoice MAX"
TIIInonStd,L5,101,"Hartford"
TIIInonStd,L5,104,"Bloomfield"
TIIInonStd,L5,111,"Pomona"
TIIInonStd,L5,112,"Valhalla"
TIIInonStd,L5,114,"Beacon"
TIIInonStd,L5,121,"Schunnemunk"
TIIInonStd,L5,130,"Putnam Valley"
TIIInonStd,L5,131,"Woodstock"
TIIInonStd,L5,134,"Esopus"
TIIInonStd,L5,151,"Mt Tom"

DSDPlus.frequencies
; OneVoice MAX
TIIInonStd,L5,101,2439,454.23125,0.0,0
TIIInonStd,L5,104,695,454.325,0.0,0
TIIInonStd,L5,111,3921,478.825,0.0,0
TIIInonStd,L5,112,2909,472.5,0.0,0
TIIInonStd,L5,114,309,451.9125,0.0,0
TIIInonStd,L5,114,2905,472.475,0.0,0
TIIInonStd,L5,121,2839,472.0625,0.0,0
TIIInonStd,L5,130,3871,478.5125,0.0,0
TIIInonStd,L5,131,2141,463.3625,0.0,0
TIIInonStd,L5,134,349,452.1625,0.0,0
TIIInonStd,L5,134,397,452.4625,0.0,0
TIIInonStd,L5,151,397,452.4625,0.0,0

 

[GTR8000]

The Goosetown sites are now reporting as H3 instead of L5, so DSD+ files will need to be updated again.

Not sure if the Triangle sites have also changed to H3 or are still L5 or something else entirely.

 

[cg]

My 2 sites I can get in the Hartford area are now showing as H3 instead of L5

 

[BM82557]

First look since the latest version was released, slowly showing the site neighbors this morning, weak signal being received --

 

[GTR8000]

Okay so Triangle still L5. TBD whether they change to H3 as well, or remain L5. Thanks for the report, appreciate someone down there contributing!