KC0CSE
Member
Is MODOT still analog?...there not coming in lately ....I would expect them to go digital soon? They are on a repeater system are they not?
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MODOT
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I'm still hearing some of their traffic in the Metro St. Louis area on VHF-Hi channels, via repeaters. Mostly road-side assistance stuff, though. I will say that I haven't made any real attempt to monitor them on purpose.
talkpair
Member
Most of the snow removal crews in the metro portion of the Kansas City district use simplex for truck-to-truck.
Because of some of the precipitation falling this afternoon, I've logged:
151.04000.........PL 123.0....heard truck out of Less Summit barn...heard truck on Stadium Drive....trucks out of the Nashua barn
151.07000.........PL 94.8....truck in Lees Summit area
151.07000.........PL 123.0....Independence area.....I-70 area out to Grain Valley
151.07000.........PL 167.9....Kansas City repeater (heard EOC requesting road report)
156.13500.........PL 94.8....heard truck near State line....another truck near Little Blue Pkwy
This frequency is one of the main channels used in the Northwest district, but seems to get some usage in the northern part of the Kansas City district:
151.13000.........PL 123.0....trucks in Liberty/Kearney area
Most of the Northwest district (St Joseph) uses 151.13 with a PL of 141.3. They seem to use the repeaters more than the Kansas City district. What little simplex traffic I've monitored uses the same 141.3 PL as the repeater outputs.
There may be more frequency/PL combinations. Most of the weather activity this afternoon appears to be south of the river.
Because of some of the precipitation falling this afternoon, I've logged:
151.04000.........PL 123.0....heard truck out of Less Summit barn...heard truck on Stadium Drive....trucks out of the Nashua barn
151.07000.........PL 94.8....truck in Lees Summit area
151.07000.........PL 123.0....Independence area.....I-70 area out to Grain Valley
151.07000.........PL 167.9....Kansas City repeater (heard EOC requesting road report)
156.13500.........PL 94.8....heard truck near State line....another truck near Little Blue Pkwy
This frequency is one of the main channels used in the Northwest district, but seems to get some usage in the northern part of the Kansas City district:
151.13000.........PL 123.0....trucks in Liberty/Kearney area
Most of the Northwest district (St Joseph) uses 151.13 with a PL of 141.3. They seem to use the repeaters more than the Kansas City district. What little simplex traffic I've monitored uses the same 141.3 PL as the repeater outputs.
There may be more frequency/PL combinations. Most of the weather activity this afternoon appears to be south of the river.
KC0CSE
Member
yes I am herring them now..
When MODOT gang plows, they do not use their repeaters as the truck radios desense the repeater output and they cannot talk truck to truck so they go simplex or direct mode.
Desense?? What's that? You mean after spending a king's ransom on super-duper expensive equipment it is not perfect in all situations in all areas?
</sarcasm>
At last I know there are at least two of us who understand the concept and how it degrades communications. Now if we could only 'splain the fallacy of one-size-fits-all to the rest of the world...
Yep, and it only took them how many years to figure this out!
Someone had asked me the RF output level of their mobiles.
At one time, I'd been told by a local Motorola tech that maintained the St Louis MODOT radios that they were 100 watt radios.
I finally found some mobiles listed on one of their regions radio system and it does show the mobile part of the license allowing 110 watt mobiles.
It was odd as many of their repeater licenses are not showing mobiles but they used too. I wonder if someone screwed up when they changed the emission designators for narrowband and accidently removed the mobiles from the license. I've seen that happen during the NB license change craziness. I actually screwed up one of our VHF repeater licenses and removed the mobiles or portables talk-around frequency when I meant to just change the emission designator to show NB.
That one I let go for now as we don't use the portables in simplex mode anyway so not breaking any rules but the license is coming up for renewal this year so I plan on adding them back at that time.
Back to the MODOT trucks and gang plowing, it does not work very well when they are talking through a repeater that may be 15 miles away but they are talking with other trucks "in the gang" that are only 40 feet or so apart from each other! Those 100 watt radios will kill the reception on the other radios from the repeater when one of the guys is talking.
I'm very near I-64 and I-270 and can hear the desense when they gang plow and forget to switch over to simplex. It sounds like CB channel 19 on a day that the band is wide open!
You almost think you are monitoring CB 19 when MODOT comes through the area with their gang plows if you base it on some of the things they talk about. A lot of just simple nonsense chatter (nothing bad though) amongst the drivers. I guess that helps them pass the time as it probably does get boring after several hours. I'm not saying that is a bad thing against them as they are trying to do their best especially when they are up against some of the 'invincible' drivers in SUV's (and plain old cars) that don't understand anything about giving the trucks some room so they can do their job! The Modot guys can actually be pretty funny sometimes and even when they are using simplex, they can still be heard a good distance away with the 100 watt radios.
I've always heard they do not intend on moving MODOT over to MOSWIN due to the amount of chatter amongst the drivers. That would probably bring several MOSWIN sites to capacity and leave no channels open for the troopers when they need the system for a true emergency.
I'd think the troopers radios could be setup with a higher priority though that would bump a MODOT user if a site was running at 100% due to chatter. With most of the MOSWIN sites only having 5 channels and only 4 really useable due to the CC, I could see those sites running at capacity during a decent snow storm.
I'd imagine some rural counties could have their highway department trucks running on Moswin though especially if they had a cruddy radio system in the first place. I'm not sure if PW type traffic is even allowed on Moswin though, even at the county level, and if not, that rule would answer that question.
I don't recall seeing any PW type talkgroups listed under rural Moswin county users but then again, I can't honestly say I've ever studied the rural counties that are actually using Moswin.
Yes, MODOT is pretty much using the same ole radio systems and repeaters they have used for years. The only change was when they narrowbanded their radio's and repeater's.
They may have swapped some of their frequencies around some amongst the districts to get around interference issues with other non MODOT users but for the most part, they are still using the same frequencies they have been licensed for, for years.
I do know around this area that one of their frequencies is used more for the 'motorist assist' channels now and I think they may have even added some UHF analog frequencies for motorist assist again but in other parts of the state.
Their main repeater here uses multiple PL's. One is used by the original MODOT guys and another PL is used by the Motorist Assist guys but all on the same repeated.
I think that is now common practice in the metro areas that have active motorist assist crews.
Personal desense horror story: a rural fire agency had a fleet of VHF 100w VX6000's. Someone said that they 'must' have 3db 5/8 wave antennas on their apparatus for better reception and I was told that was an unchangeable absolute. 3db gain meant their ERP went to >200w. Never mind the licensing.
The region put up a JPS SNV voted analog repeater command system with multiple transmitters determined by voted site selection (STARS). Since their uplink voting tied full-stroke at several sites the system would 'vote' them to the central site instead of their local tower. You know what desense did to truck-to-truck through a repeater ten miles away. Dispatch and the rest of the region could hear them just fine but they couldn't talk 100 yards truck-to-truck. I was clearly told in no uncertain terms that the new system was junk, even though their district had 95% 3w portable coverage and voted perfectly as designed.
The fix was to crank their apparatus radios down to 10w on system channels. Having been down this road before and knowing that most firefighters subscribe to the 'Binford - too much is always better' theory, I reversed the transmitter power settings so "High' was really 10w and ''Low' was 100w. That way the 'Low Power' icon wouldn't show on normally used channels and raise suspicion. I 'splained that 'Low' on the neighbor's simplex channels was normal and they were none the wiser.
They could now talk flawlessly on the Binford-Mandated "High Power" and 3db antennas after I fixed the regional 'junk' system.
My lies may send me to Hell, but I'll go with a clear conscience.
The region put up a JPS SNV voted analog repeater command system with multiple transmitters determined by voted site selection (STARS). Since their uplink voting tied full-stroke at several sites the system would 'vote' them to the central site instead of their local tower. You know what desense did to truck-to-truck through a repeater ten miles away. Dispatch and the rest of the region could hear them just fine but they couldn't talk 100 yards truck-to-truck. I was clearly told in no uncertain terms that the new system was junk, even though their district had 95% 3w portable coverage and voted perfectly as designed.
The fix was to crank their apparatus radios down to 10w on system channels. Having been down this road before and knowing that most firefighters subscribe to the 'Binford - too much is always better' theory, I reversed the transmitter power settings so "High' was really 10w and ''Low' was 100w. That way the 'Low Power' icon wouldn't show on normally used channels and raise suspicion. I 'splained that 'Low' on the neighbor's simplex channels was normal and they were none the wiser.
They could now talk flawlessly on the Binford-Mandated "High Power" and 3db antennas after I fixed the regional 'junk' system.
My lies may send me to Hell, but I'll go with a clear conscience.
I'm not hearing any traffic on any of the VHF MODOT frequencies in the NW district at all. Does anyone have any information on what is going on up here. I've looked at all the FCC frequencies licensed directly to MODOT and loaded them into my scanner but I've got nothing working.
I hadn't had any luck hearing any of the MODot plows this winter at all...nor their weather forecasts they used to broadcast over their frequencies...think maybe they've pretty much went to cell phones...
I don't know about the cell phones but I would agree they aren't where the FCC and RadioReference think they are. I did find a bid request on the Mo.gov page from back in 2012 requesting a bid for communications consulting for MODOT. It was a one year at a time bid renewable for up to 3 years. I did not however find the bid acceptance.
I also found 12 licenses on the Wireless USA network for Jeff City and the FCC page showed those same frequencies with way more than 12 licenses. I suspect they may have given up the assigned frequencies in NW Mo to let busier areas like KC and St. Louis have full use. I went to school with a guy who spent his whole working career working for them in NWMO. Perhaps I can ping him to find out what happened to them. It could be they moved over to Midwest Mobile's UHF repeater network here in NWMO and are leasing air time from them.
I also found 12 licenses on the Wireless USA network for Jeff City and the FCC page showed those same frequencies with way more than 12 licenses. I suspect they may have given up the assigned frequencies in NW Mo to let busier areas like KC and St. Louis have full use. I went to school with a guy who spent his whole working career working for them in NWMO. Perhaps I can ping him to find out what happened to them. It could be they moved over to Midwest Mobile's UHF repeater network here in NWMO and are leasing air time from them.
talkpair
Member
Modot-NW used the VHF repeaters during some of the snow events this winter.
Unless something changed recently, I would say that they are still in use, just not much activity.
They were heard this past winter reading forecasts over each repeater in the district, and asked for road reports periodically.
St Joseph, Martinsville, Quitman (Skidmore) and Polo all use the repeater output frequency of 151.13 mHz.
Harris and Avalon use an output frequency of 151.04 mHz.
Everything in the district uses a repeater output tone of 141.3 Hz.
Unless something changed recently, I would say that they are still in use, just not much activity.
They were heard this past winter reading forecasts over each repeater in the district, and asked for road reports periodically.
St Joseph, Martinsville, Quitman (Skidmore) and Polo all use the repeater output frequency of 151.13 mHz.
Harris and Avalon use an output frequency of 151.04 mHz.
Everything in the district uses a repeater output tone of 141.3 Hz.
iamhere300
Member
A motorola tech who took care of MODOT radios? MODOT is self maintained.
Anyways, they have used LOTS of 45-50 watt radios, and still do. A large number of supervisors, and motorist assist units have MOSWIN radios, for interoperability, as do their interop trailers, but they are in addition to their regular VHF radios.
I am not aware of any MODOT operations that just use MOSWIN.
Yep, I think that came out wrong as that conversation was from far back when they were building a new maintenance facility near here. That maintenance facility was better located to help out with the local roads under MODOT maintenance but I think its main purpose was to supervise and support all the cameras ran by the "Gateway Guide" division. Gateway Guide was something new for MODOT and back then, they were lucky if they had 10 cameras up and running. Gateway Guide was still in its infancy.
The tech I talked with was more likely a former Motorola tech who was now employed by the state as a radio tech for MODOT.
I do know his primary job was changing then as the gateway guide camera system used a lot of microwave links which is what he would be working on while new hires were going to work on the VHF systems in use in the metro area.
Now this conversation was around 15 years ago or so, so things could be different from what I think I remember. I'd also imagine the radio tech that I met has retired by now as he was getting up there in age when I met him.
I don't recall the radio models in use then but they were large, very large.
Not something you would mount under a dash! They had control heads for the user interface,
I'd need to look through some old Motorola literature and could probably ID the radios that way.
Some smaller supervisor type vehicles did have smaller and more modern radios in them and I think he said that was what would go into any new vehicle purchase or replace a faulty radio. I would not be surprised to learn that the old mobile radios has vacuum tubes in them for the PA section.
I think the control heads were wired with the same 25 pair phone wiring and connectors that were used by Western Electric on the old 5 button phones commonly found in old offices.
Anyway, thanks for catching my mistake!
edit: I've also not seen or heard any MODOT maintenance vehicle's come up on MOSWIN but I have heard Motorist Assist units on Moswin.
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They mainly use their MODOT frequencies for severe weather. At least it's like that down in Pulaski county. I hardly ever hear them even though a MODOT shed is just 2 miles away from me.
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