I'm going to be slightly disappointed if I'm late to the party but I found a pattern. All Public Safety P25 systems in the state with the exception of Portland and WCCCA/CCOM follow a pattern of talkgroups and Unit IDs. The first digit of both the talkgroups and unit IDs follow an alphabetical list of counties. You can see this on Salem P25, SW 7 County Interoperable Public Safety Radio Partnership, Frontier Digital Network and the Oregon State Radio Project.
1 BAKER
2 BENTON
3 CLACKAMAS
4 CLATSOP
5 COLUMBIA
6 COOS
7 CROOK
8 CURRY
9 DESCHUTES
10 DOUGLAS
11 GILLIAM
12 GRANT
13 HARNEY
14 HOOD RIVER
15 JACKSON
16 JEFFERSON
17 JOSEPHINE
18 KLAMATH
19 LAKE
20 LANE
21 LINCOLN
22 LINN
23 MALHEUR
24 MARION
25 MORROW
26 MULTNOMAH
27 POLK
28 SHERMAN
29 TILLAMOOK
30 UMATILLA
31 UNION
32 WALLOWA
33 WASCO
34 WASHINGTON
35 WHEELER
36 YAMHILL
37 No Known Talkgroups or Unit IDs
38 OREGON STATE POLICE
39 No Known Talkgroups or Unit IDs
40 OREGON DEPARTMENT OF TRANSPORTATION
There are a couple exceptions to this on the Oregon State Radio Project P25. There are some patches from early on in the system build, as well as the Unit ID holding the patch that start with 40, likely since ODOT maintains the system.
1 BAKER
2 BENTON
3 CLACKAMAS
4 CLATSOP
5 COLUMBIA
6 COOS
7 CROOK
8 CURRY
9 DESCHUTES
10 DOUGLAS
11 GILLIAM
12 GRANT
13 HARNEY
14 HOOD RIVER
15 JACKSON
16 JEFFERSON
17 JOSEPHINE
18 KLAMATH
19 LAKE
20 LANE
21 LINCOLN
22 LINN
23 MALHEUR
24 MARION
25 MORROW
26 MULTNOMAH
27 POLK
28 SHERMAN
29 TILLAMOOK
30 UMATILLA
31 UNION
32 WALLOWA
33 WASCO
34 WASHINGTON
35 WHEELER
36 YAMHILL
37 No Known Talkgroups or Unit IDs
38 OREGON STATE POLICE
39 No Known Talkgroups or Unit IDs
40 OREGON DEPARTMENT OF TRANSPORTATION
There are a couple exceptions to this on the Oregon State Radio Project P25. There are some patches from early on in the system build, as well as the Unit ID holding the patch that start with 40, likely since ODOT maintains the system.
