MOSWIN Tower Signal Indicators

[rbritton1201]

I notice on my scanner that when the scanner scans through MOSWIN towers, there is fully deflected signal bar at all times displayed on some MOSWIN towers but no carrier. I assume that the fully deflected signal bars without carrier are from MOSWIN towers that are apparently in range. I assume when the scanner scans over other MOSWIN towers that don't display a constant signal bar on the scanner, that those MOSWIN towers are not within range.

What I am not used to seeing with respect to MOSWIN is that from analog systems you only see a deflected signal bar when there is a carrier transmission. But, some MOSWIN towers on the scanner display a fully deflected signal bar on the scanner's display at all times, like you would experience if there were a continuous open key were they analog towers.

So, admittedly not really knowing exactly how this technology works, it appears that MOSWIN towers in range are constantly transmitting. Of course, the analog frequencies display signal only when there is a carrier, and that makes perfect sense. I'm trying to understand the technology a little better, and making uninformed assumptions as to what I'm seeing on the scanner with respect to constant carrier from some MOSWIN towers.

 

[wbloss]

All MOSWIN towers have a "control channel" which is an RF digital data stream. So yes, there is a constant (data) signal for your scanner to latch onto. If the data stream does not indicate a conversation is happening, the scanner moves on to the next tower/site you have programmed to see what's up there. In the RadioReference database, the control channels are designated in red and have a "c" after the frequency. More if you want it.

 

[rbritton1201]

Thanks for confirming what I theorized was going on with the MOSWIN towers. I would like to know as much as possible, so if you have time to elaborate even further, then it would be much appreciated. Does the data stream enable the cars to process 28s and 29s, 10-99 inquiries, communicate with the main base through a data link, etc...or is it just a characteristic of the infrastructure of the MOSWIN system, and if so, why the constant data stream? Thanks again!

More if you want it.

 

[nd5y]

Does the data stream enable the cars to process 28s and 29s, 10-99 inquiries, communicate with the main base through a data link, etc...or is it just a characteristic of the infrastructure of the MOSWIN system, and if so, why the constant data stream?

The "data stream" is a trunking control channel. Most types of trunked radio system (and cellular telephone systems) have control channels. Read this.

Trunking Basics - The RadioReference Wiki

wiki.radioreference.com

 

[stlouisx50]

Great questions. So I can't confirm mshps computer system running off the tower sites but I can tell you how the radios work so you will understand.

When a radio is turned on it begins to search for the strongest tower. Just like your cell phone. The radio continues to communicate with the tower to see if its the best signal.

While it's doing this, note if a tower does not have a radio signed into it, it may not be heard even though the, for example, "mshp", is actually transmitting. This is due to the transmission being broadcast to only active towers with subscribers..
I belive some sites will always be active respective to the dispatch being located by a particular tower, or even another agency signed in on a tower as they are traveling though.

So if say, Springfield Police have to come to St. Louis, their radio may wake up a tower that the mshp uses if their patrolman is on duty from 6-2. You wouldn't hear mshp after 2 on most cases because no subscriber. However if Springfield pd activated the tower as they traveled through, you would hear Springfield until they went to another tower.
With that said, they do restrict radio traffic based on towers they want to cover for a particular area. So Springfield PD could talk on the travel channel, but you won't hear dispatch. The same with you won't hear mshp dispatch, unless mshp signs on their radios to a tower.

 

[nd5y]

The computers probably use AT&T or Verizon or some other cellular carrier. A trunking control channel is not capable of handling that type of data. They could run data over voice channels but the data rate is only 9600 bps which is too slow for something like that. If they did then there would be craploads of posts from people wondering what all the icall or non-voice talkgroup activity was.

 

[kruser]

The computers probably use AT&T or Verizon or some other cellular carrier. A trunking control channel is not capable of handling that type of data. They could run data over voice channels but the data rate is only 9600 bps which is too slow for something like that. If they did then there would be craploads of posts from people wondering what all the icall or non-voice talkgroup activity was.

Our county Slater system does use the voice channels for data here. It's used with their MDT's but the data sent back and forth is basically just text so 9600 baud works out fine for their needs. I know they can also do video over the MDT's but that does appear to use a cellular network as you won't see a data channel being used on the trunk system when they are doing video images or other higher bandwidth tasks.
On Moswin, it's very rare that I've seen a channel used for data on the VHF or 700 MHz sites. I do see data used on the St Louis city 800 MHz site 201 but it's always a city user terminal and never a state user that's using a channel for data.
Moswin State Patrol users mainly use voice for record check type info much like they did when they had low band radios only.
I can't speak for how most of the counties using Moswin today handle this. I suspect most are using MDT's with cellular radios like you suggested.

 

[rbritton1201]

Thanks for all the good information everybody! I've been reading through the documentation links that were sent, as well as the explanations in the posts, and I feel that I am understanding more about how things work. But, just to confirm...

So, if I am seeing five bars on the signal bar off of the Shirley and Rolla towers, and I'm in Franklin County, then I should be able to hear traffic on those towers, provided the talk groups are programmed into my scanner for the subscribers programmed into those towers, or I should be able to hear transmissions off of those towers for those that are not regular subscribers that may be traveling, and have activated the tower in transit, and are transmitting? Am I understanding that correctly?

Conversely, I'm seeing only about two bars from the Willow Springs tower, and one bar from the Poplar Bluff tower. But, even at that, I should be able to receive signals from subscribers that have activated those towers, provided their talk groups are programmed into my scanner to correlate with the respective towers in their coverage area, or I won't hear voice transmissions from them. Am I correct that the talk groups for agencies I want to listen to need to be programmed into the scanner as subscribers to a particular tower, or they need to have activated a tower by being in close enough proximity to the tower in question as travelers going past a tower while transmitting, or I won't hear anything from them out of a particular tower that might otherwise show a strong signal strength?

Of course, I'm not hearing any voice traffic on any of these four towers. I can understand that with respect to Shirley and Rolla, assuming that Iron and Reynolds County are probably not subscribers on those two towers, and not in close enough proximity to them, even if they were subscribers to those towers. So, I wouldn't typically hear anything from them, unless they were traveling out of their service area, and transmitting in close proximity to the service areas of those towers as travelers, correct?

But, I should be hearing something from the Willow Springs tower, whose MSHP talk groups are programmed into my scanner. Since I'm seeing two bars, but I'm not hearing any voice traffic on that tower, which is a surprise to me, since Willow Springs tower should have quite a bit of MSHP voice traffic. But, maybe two bars just doesn't cut it. If it's anything like a a cell phone, two bars isn't much, and frequently won't result in decent cell service. But, as I mentioned before, I did hear voice traffic from Troop G one time yesterday, but didn't notice which tower it came from, I assume it was probably the Willow Springs tower.

With respect to the Taum Sauk tower, I'm seeing about 2 bars from it, and I do have talk groups entered into the scanner for Reynolds County Sheriff, but while I can see the 2 bars of signal strength, I hear no voice traffic. I seems I should be hearing voice traffic from MSHP and Reynolds County off the Taum Sauk tower. I know that particular area, Reynolds County, is supposedly a radio propagation nightmare, with all the hills and valleys, so Troop G would most certainly be entered into Taum Sauk as subscribers as well as Reynolds County.

 

[Arkmood]

But, as I mentioned before, I did hear voice traffic from Troop G one time yesterday

Troop G seems a bit of a mystery (to me)... can only speak for Tr.G Ozark Co. and I rarely monitor much coming out of there, have questioned this group about it ...

 

[rbritton1201]

I think the MOSWIN maps are screwed up, and that sometimes we are programming what we think might be a particular tower (Willow Springs Troop G), when what we are programming into the scanner is a completely different tower. There are too many instances of these towers sometimes not acting as we expect them to. I've thought of programming in ALL the towers in the State, letting the scanner do it's stuff, to see if it hits on the right one based on talk group. Problem is, it takes FOREVER for the scanner to go through them all, and you would have to babysit the scanner to notice when everything comes together for a particular area you want to monitor.

Troop G seems a bit of a mystery (to me)... can only speak for Tr.G Ozark Co. and I rarely monitor much coming out of there, have questioned this group about it ...p,

 

[kruser]

So, if I am seeing five bars on the signal bar off of the Shirley and Rolla towers,

With respect to the Taum Sauk tower, I'm seeing about 2 bars from it,

What are the exact frequencies shown on the scanner when you see these signal bars on the Shirley, Rolla and Taum Sauk towers?
That may not display on the radio though but if you use something like ProScan, then the actual tuned frequency will be displayed.

And I forget but are you using a 536HP model scanner?

I find it highly suspicious you are seeing full bars in Union, MO from Rolla or Shirley.
Are the sites you programmed 700 MHz sites by chance?

 

[Arkmood]

I think the MOSWIN maps are screwed up, and that sometimes we are programming what we think might be a particular tower (Willow Springs Troop G), when what we are programming into the scanner is a completely different tower.

Tower information is (almost) correct for Theodosia (Ozark Co.)... been monitoring for the last 2 years - just a paucity of transmissions...

 

[kruser]

I think the MOSWIN maps are screwed up, and that sometimes we are programming what we think might be a particular tower (Willow Springs Troop G), when what we are programming into the scanner is a completely different tower. There are too many instances of these towers sometimes not acting as we expect them to.

The maps are mostly fine. It's the fact they reuse frequencies across the state where people become confused as I'd explained in one of your threads back in 2020 I think.

The site names may not actually represent the nearest town to a tower site. They could use a known landmark for a site name for example.

On the Moswin database page, click on any sites "name", not county and it will show you a map where that site is located. Some of the site coordinates are off a bit but still reasonably close.
That same map that opens will also have range info along the left side that will give you an idea about how far you may be able to receive the site. That range can be off though due to terrain and other factors like your altitude in relation to the sites tower but it's still a good starting point to give you an idea if you are trying to hear a site will out of your range.
The colored range circle shown when you click a sites name is the estimated signal coverage area. Again, it's just an estimate as radio waves don't always follow a circular path.

 

[rbritton1201]

I'll check it, and let you know...I am using Proscan. I notice that when remote monitoring using Proscan, the frequency displayed at the bottom left of the faceplate on the scanner doesn't change. It stays the same as the scanner is scanning. It might just be that remote monitoring aspect of Proscan doesn't display the change in frequency. So, I need to check the scanner itself and report back to you on what I'm seeing within the scanner's frequency window. But, I believe the frequencies do change as it scans when viewing the actual scanner front face frequency window.

With regard to Rolla and Shirley, I'm closer to them than you are, my being in Franklin County, but yeah, that's a distance. But, I do have a Discone antenna mounted up in the attic, about 25 feet off the ground, so maybe that helps. Believe me, I'm surprised at the signal strengths I'm seeing off these far distant towers like Poplar Bluff, two bars from Taum Sauk, 2 bars from Willow Springs...shocking!

But, that's why I sometimes wonder if what is programmed into the scanner based on the MOSWIN data base via the Uniden Sentinel Program is accurate. But, Uniden claims to get it directly from Radio Reference, and it can be updated anytime from the Sentinel software. That's why I'm suspicious that the data base from MOSWIN is off at times. I don't have any problem with respect to MSHP Metro and Rural, or the local municipalities around me, and in the St. Louis metro area, but sometimes things just seem kind of off with some of these towers.

What are the exact frequencies shown on the scanner when you see these signal bars on the Shirley, Rolla and Taum Sauk towers?
That may not display on the radio though but if you use something like ProScan, then the actual tuned frequency will be displayed.

And I forget but are you using a 536HP model scanner?

I find it highly suspicious you are seeing full bars in Union, MO from Rolla or Shirley.
Are the sites you programmed 700 MHz sites by chance?

 

[rbritton1201]

I believe the Rolla and Shirley frequencies are in the 700 Mhz band range. The exact frequency of the towers for Iron County and Reynolds County is 152.600000 Mhz, and it never changes from one tower to the next.

What are the exact frequencies shown on the scanner

 

[kruser]

I believe the Rolla and Shirley frequencies are in the 700 Mhz band range. The exact frequency of the towers for Iron County and Reynolds County is 152.600000 Mhz, and it never changes from one tower to the next.

Okay,

I'm not certain on the 700 sites without the frequencies but if the towers for Iron and Reynolds are always showing 152.600, you are only heaing the Imperial, MO site 3-27. It's control channel is 152.600 which would explain the great signal strength.
I don't know why you would have 152.600 entered in for the Iron or Reynolds county sites though as neither of those sites use 152.600 for a voice or control channel.

Did you somehow lump several sites frequencies under one site?
That would surely make a mess of things when it comes to trying to monitor Moswin!

Madison and Montgomery counties in Missouri are the only other sites known to use 152.600. And it's a voice channel on both of those sites. Montgomery county should be in range of you so if you entered all the voice channels in, your radio will still stop on the Imperial site 3-27 control channel signal but display Montgomery County. Same thing with Madison county if you entered in all it's voice channels. The radio will see the 152.600 control channel signal from the Imperial site but the scanner display will show Madison County if that's how you named it.

If you entered all the voice channels in from the database, my advice would be to remove all of them and only leave the primary and alternate control channels for each VHF site you have programmed. The control channel is all that's needed to hear the voice channels. The control channel tells the scanner which frequency to tune when a voice channel is requested by a user radio.
In theory, just the primary control channel colored red is all that's needed for each site but they do on occasion swap to the alternate control channel (blue color) so it's usually wise to program both of those for each site.

The 700 MHz sites can be a bit trickier as they have been swapping frequency sets around between the 700 mHz sites across the state so what you see for the 700 sites frequencies may not always be correct in the database.
You can always enter the 700 MHz frequency you are receiving in as a conventional channel. The scanner should then show you the true site number the signal is really coming from. I think (not positive with the 536HP) you can also hold on a 700 MHz sites control channel and the display should alternate between the name you gave the site and the true site number. Use the true site number and see if it matches the name you entered when you match the site number up with the Moswin database at the link below.

Missouri Statewide Wireless Interoperable Network (MOSWIN) Trunking System, Statewide, Multi-State

Missouri Statewide Wireless Interoperable Network (MOSWIN) Trunking System Profile

www.radioreference.com

edit: the more I think about this, the more I think you must either be scanning one list with all the sites frequencies that also contains 152.600 in that list or somehow you added 152.600 into each VHF site you are scanning.

Your mention of 152.600 never changing on the screen pretty much indicates this as the problem.
If you don't intend on monitoring the Imperial site, remove every instance of 152.600 from your favorites that you are scanning and see what happens. The Imperial site should have a decent signal on 152.600 at your location as that site has really good coverage across our area.
That would be the reason you always see 152.600 displayed.

 

[rbritton1201]

I agree, there has to be some kind of error to have such strong signal indicators, and a frequency displayed that isn't even entered into programming. I double checked the list of frequencies entered into the favorites list for Reynolds and Iron County, and nowhere does 152.600 Mhz. show up in my programming.

I'm going to start with a fresh install of programming. I'm going to format a new card, and start from scratch. I just can't explain where that frequency of 152.600 is coming from. I saved my original profile for my local area, and I'm going to reinstall it to the card for the scanner.

I've been experimenting with Reynolds and Iron County just to see what might be possible with respect to reception, and because my brother lives in Reynolds County, works in Iron County, and I was hoping I might be able to pick them up. Then he could tap into my server and listen on his cell phone. But, I've come to the conclusion that whatever I'm picking up with respect to signal strength isn't the towers in those areas, and that the likelihood of making this scenario work isn't probably a realistic possibility, due to the distance their towers are from Franklin County, where the scanner is based.

Okay,
I'm not certain on the 700 sites without the frequencies but if the towers for Iron and Reynolds are always showing 152.600, you are only heaing the Imperial, MO site 3-27. It's control channel is 152.600 which would explain the great signal strength.

 

[stlouisx50]

I can confirm that he's likely only picking up Imperials site. When I'm in Warren County and used my Jpole, I could get a few bars out of Montgomery and I am closer, but I could get 1 bar from Imperial. Imperial and Washington Counties really boom.

 

[stlouisx50]

I'll check it, and let you know...I am using Proscan. I notice that when remote monitoring using Proscan, the frequency displayed at the bottom left of the faceplate on the scanner doesn't change. It stays the same as the scanner is scanning. It might just be that remote monitoring aspect of Proscan doesn't display the change in frequency. So, I need to check the scanner itself and report back to you on what I'm seeing within the scanner's frequency window. But, I believe the frequencies do change as it scans when viewing the actual scanner front face frequency window.

With regard to Rolla and Shirley, I'm closer to them than you are, my being in Franklin County, but yeah, that's a distance. But, I do have a Discone antenna mounted up in the attic, about 25 feet off the ground, so maybe that helps. Believe me, I'm surprised at the signal strengths I'm seeing off these far distant towers like Poplar Bluff, two bars from Taum Sauk, 2 bars from Willow Springs...shocking!

But, that's why I sometimes wonder if what is programmed into the scanner based on the MOSWIN data base via the Uniden Sentinel Program is accurate. But, Uniden claims to get it directly from Radio Reference, and it can be updated anytime from the Sentinel software. That's why I'm suspicious that the data base from MOSWIN is off at times. I don't have any problem with respect to MSHP Metro and Rural, or the local municipalities around me, and in the St. Louis metro area, but sometimes things just seem kind of off with some of these towers.

I think I'm understanding you correctly, your scanner is stuck on one frequency. Are you hearing units or are you missing conversations?
It almost sounds like your scanner is stuck on the control carrier freq. Many scanners don't automatically disclose raw data audio, but they do get stuck on it when scanning if programed as a conventional channel or searching. At one time they did have raw data.
If you are picking up no audio and you see one freq. all the time, you may just be showing the carrier freq when a unit keys up rather than the voice freq. Many times these are an option to choose in settings.

I also was wondering if you programed in the frequencies as conventional rather than a P25 system.

I want to make sure I understand ya.

 

[rbritton1201]

Let me see if I can explain my understanding without confusing myself, and everyone else, LOL!

I'm seeing a strong control channel transmission off of a tower other than the one I intended to program into the scanner because both towers must have an identical frequency programmed into each of them.

The towers are far apart from each other geographically. So, the one I'm picking up that shows a strong control channel signal indicator must have the same frequency(s) that the one that is far away has in it. So, I'm seeing a strong control channel signal indicator off of the close tower, and thinking it's the control channel signal indicator from the far away tower.

But, the talk groups for the far away tower aren't programmed into the closer tower that shows a strong control channel signal indicator, and the tower that is far away doesn't have the signal strength to make the trip all the up to where I'm located. So, in actuality, I'm not seeing anything off the control channel of the far away tower, and I'm not hearing any voice traffic off of the closer tower because the talk groups programmed into the scanner are for the tower that's far away.

Everything is working fine now, and I'm receiving all the transmissions I'm intending to monitor, so I'm good to go. I just didn't formerly understand the above at the point where I initiated this post.

I think I'm understanding you correctly, your scanner is stuck on one frequency. Are you hearing units or conversations?
It almost sounds like your scanner is stuck on the control carrier freq. Many scanners don't automatically disclose raw data audio, but they do get stuck on it when scanning if programed as a conventional channel or searching. At one time they did have raw data.
If you are picking up no audio and you see one freq. all the time, you may just be showing the carrier freq when a unit keys up rather than the voice freq. Many times these are an option to choose in settings.

I also was wondering if you programed in the frequencies as conventional rather than a P25 system.

I want to make sure I understand ya.