Is there a way to determine the protocol for this system, and possibly what order?

[saioke]

Using an SDR, I recently discovered several frequencies from the General Mills plant in Wellston here in Ohio. Every radio seems to have a small "blip" when nobody is talking. When they do, it seems that the replies to said person seem to be split between other frequencies. So, this has to be some sort of trunking system. Question is, what type? Definitely not P25 and it doesn't seem like basic DMR to me. I found a "rest" channel among those frequencies (461.350) and it seems there's a lot of chatter happening on (463.5375, 463.3375). I see other weird blips in the area, but the blips on the waterfall don't correspond with the General Mills facility so I wrote them off. Not seeing any activity on most of the other frequencies listed on the FCC website.

Just wondering if anyone could help identify this - ULS License - Industrial/Business Pool, Conventional License - WQCJ973 - GENERAL MILLS-WELLSTON PLANT - Frequencies Summary system. Connect+ maybe? I feel like the factory would be pretty interesting to listen to, and they're ALWAYS active. Unfortunately they aren't in the RR system. Perhaps they could be, if we can figure this out?

 

[saioke]

Just noticed that the radio service says "IG - Industrial/Business Pool, Conventional" so I guess it's not a trunked system. In fact, 461.350 isn't the "rest" channel after all. That frequency would be 461.200 which isn't even in the General Mills FCC database. Still odd that I don't always hear replies on one particular frequency when it comes to General Mills. Still, I think I'll just assume it's some sort of GMRS setup.
Now I'm going to look into what this rest channel is. could just be a glitch perhaps, but DSD is saying it's using Cap+.

 

[ecps92]

Just noticed that the radio service says "IG - Industrial/Business Pool, Conventional" so I guess it's not a trunked system. In fact, 461.350 isn't the "rest" channel after all. That frequency would be 461.200 which isn't even in the General Mills FCC database. Still odd that I don't always hear replies on one particular frequency when it comes to General Mills. Still, I think I'll just assume it's some sort of GMRS setup.
Now I'm going to look into what this rest channel is. could just be a glitch perhaps, but DSD is saying it's using Cap+.

Don't assume, many a system has been found not updating the FCC licenses,, to also include those who are licensed as trunked, but operating some frequencies as conventional.

GMRS would not be in the 461 band, but 462/467 specific channels, did you mean GM as in General Mills, vs General Mobile Radio Service

 

[dave3825]

recently discovered several frequencies from the General Mills plant in Wellston here in Ohio

I found a "rest" channel among those frequencies

could just be a glitch perhaps, but DSD is saying it's using Cap+.

Not a glitch. Rest channels are used in Cap+ trunked systems. Look in the DSDPlus notes file as there is a section describing how to map a Cap+ system.

 

[mtindor]

Using an SDR, I recently discovered several frequencies from the General Mills plant in Wellston here in Ohio. Every radio seems to have a small "blip" when nobody is talking. When they do, it seems that the replies to said person seem to be split between other frequencies. So, this has to be some sort of trunking system. Question is, what type? Definitely not P25 and it doesn't seem like basic DMR to me. I found a "rest" channel among those frequencies (461.350) and it seems there's a lot of chatter happening on (463.5375, 463.3375). I see other weird blips in the area, but the blips on the waterfall don't correspond with the General Mills facility so I wrote them off. Not seeing any activity on most of the other frequencies listed on the FCC website.

Just wondering if anyone could help identify this - ULS License - Industrial/Business Pool, Conventional License - WQCJ973 - GENERAL MILLS-WELLSTON PLANT - Frequencies Summary system. Connect+ maybe? I feel like the factory would be pretty interesting to listen to, and they're ALWAYS active. Unfortunately they aren't in the RR system. Perhaps they could be, if we can figure this out?

You can identify Nexedge Type D and DMR Cap+ blips. When the blips occur, at the bottom of the DSDPlus Event Window it'll tell you what it is.

If it's a bad signal, it can erroneously detect things. If the signal is good it should easily detect.

 

[W8UU]

I live in Wellston but don't monitor General Mills. I do know they have an in-plant digital UHF radio system on business band frequencies. That's a huge facility with a lot going on around the clock. MotoTRBO?

 

[saioke]

You can identify Nexedge Type D and DMR Cap+ blips. When the blips occur, at the bottom of the DSDPlus Event Window it'll tell you what it is.

If it's a bad signal, it can erroneously detect things. If the signal is good it should easily detect.

Yeah it's not the greatest signal honestly. In fact, today I can't even pick it up but the clouds are thick, wind is insane and we may see some severe weather later in the day. When I could pick it up, I needed to max out the gain. I'm about 6-7 miles away from the General Mills facility and the building is huge, thick walls, machinery, etc. I'm sure I don't even pick up every radio in that place.

If it is a cap+ system, wouldn't I need to find the LCN? That probably isn't possible without physical access to a radio?

 

[dave3825]

If it is a cap+ system, wouldn't I need to find the LCN? That probably isn't possible without physical access to a radio?

Did you look in the DSDPlus notes as suggested?

Not a glitch. Rest channels are used in Cap+ trunked systems. Look in the DSDPlus notes file as there is a section describing how to map a Cap+ system.

It tells one how to map Cap+ systems (lcn numbers)

 

[saioke]

Did you look in the DSDPlus notes as suggested?



It tells one how to map Cap+ systems (lcn numbers)

Apologies, I missed your post. I'll take a gander as soon as I'm free later tonight. Would be fun to figure this out.

 

[dave3825]

If its a slow system it will take longer. Believe that plant makes Totinos pizza's and pizza rolls.

DSD+ v2.10
Cap+ monitoring
---------------

Follow these steps to monitor / follow the rest channel and voice calls on a Cap+ system

a) select a network ID

Cap+ systems do not broadcast a network ID

If the system has been added to the RadioReference database, use its page number

Otherwise, assign the system a unique NID (9999, for example)

b) create an entry in the DSDPlus.networks file

Example:

Cap+, 9999, "Mayberry PD"

c) if the network has multiple sites, create entries in the DSDPlus.sites file

Example:

Cap+, 9999, 1, "North"
Cap+, 9999, 2, "South"
Cap+, 9999, 3, "East"
Cap+, 9999, 4, "West"

d) for each known system frequency, create a channel record in the DSDPlus.frequencies file

Initially, use invalid channel numbers

Example:

; Mayberry PD North

Cap+, 9999, 1, 99, 450.5000, 0.0, 0
Cap+, 9999, 1, 99, 451.2625, 0.0, 0
Cap+, 9999, 1, 99, 454.9125, 0.0, 0
Cap+, 9999, 1, 99, 455.5000, 0.0, 0

e) tune CC FMPA/FMP24 to an active system channel (note: TCP link required)

CC DSD+ will scan the DSDPlus.frequencies file for a Cap+ record with the same frequency;
The first matching record will be used

CC DSD+ will use the frequency record to establish the system's network ID

CC DSD+ will use the NID to display the network and current site names

f) at some point, DSD+ should determine the channel's ordering
and display it in the event log window

Example:

"450.500000 is first Cap+ repeater (Ch1 and Ch2)"

Use the information to edit the channel's record in the DSDPlus.frequencies file

Note: continue to use invalid channel numbers

Example:

Cap+, 9999, 1, 101, 450.5000, 0.0, 0

g) repeat e) and f) for each active system channel

Example:

"451.262500 is third Cap+ repeater (Ch5 and Ch6)"
"454.912500 is fourth Cap+ repeater (Ch7 and Ch8)"
"455.500000 is second Cap+ repeater (Ch3 and Ch4)"

Cap+, 9999, 1, 101, 450.5000, 0.0, 0
Cap+, 9999, 1, 105, 451.2625, 0.0, 0
Cap+, 9999, 1, 107, 454.9125, 0.0, 0
Cap+, 9999, 1, 103, 455.5000, 0.0, 0

h) when the ordering of all of a site's active channels has been determined,
edit the channel records so they have the correct channel numbers

Example:

Cap+, 9999, 1, 1, 450.5000, 0.0, 0
Cap+, 9999, 1, 3, 455.5000, 0.0, 0
Cap+, 9999, 1, 5, 451.2625, 0.0, 0
Cap+, 9999, 1, 7, 454.9125, 0.0, 0

CC DSD+ will now automatically direct CC FMPA/FMP24 to follow the rest channel
and direct VC FMPA/FMP24 to follow voice calls

i) in the future, to monitor this site, tune CC FMPA/FMP24 to the current rest channel

 

[saioke]

If its a slow system it will take longer. Believe that plant makes Totinos pizza's and pizza rolls.

Yup, they always seem to be active around the clock, including plant engineers. They also make cereal. The factory in Wellston is the largest General Mills facility in the US. Actually, I'm pretty sure most of the money the city of Wellston makes comes from that factory lol. My brother used to work there, and his wife still currently does.

 

[W8UU]

The antennas for that system are on a 30' tower on the roof of the building. A mile out in any direction, the plant is surrounded by hills. They may use some leaky coax or in-building antennas because of all the concrete and metal. That's just a guess -- I'm not certain. The system isn't designed to cover too far beyond the property line. I couldn't clearly hear the old VHF analog system they used 25 years ago when I lived in Jackson. Not surprise you struggle to pick up the UHF system five miles out.

 

[saioke]

Only 30' feet? Sheesh, The antenna I'm using is a simple magnetic antenna made to mount on a car, only about 10 feet up on my roof, single story home. I'm surprised I can pick up any radio in that facility lol. Especially considering I'm also surrounded by hills. Not amazing at picking up the 700-900Mhz range for MARCs though. Oddly enough, I can pick up the Jackson MARCs site better than the Wellston one, and the Jackson site is farther by miles lol. This antenna is strange.

I'd like to mount it higher but honestly I can't do heights. Hard enough on me to climb 10 feet. Anyway, apologies for rambling. I've had no more luck picking up the rest channel, but our weather hasn't been the greatest. Hope those winds last night didn't cause any damage around your property. This year I think it's going to be one of those summers where we end up getting severe storms every week. Hopefully not, but just a feeling.