Some Random Thoughts After Monitoring Around The Bands In The Twin Cites The Past Few Weeks

[JASII]

I have spent some time monitoring the various bands the past few weeks. Here are some random thoughts after listening for a while:

-Low band is essentially dead around here. Yes, I know Eden Prairie still pages on VHF low band and the Army National Guard uses it, but beyond that, it is pretty much dead.

-VHF high band has changed a lot since ARMER started some years back. Yes, there is still fire paging there. Our neighbors in Wisconsin use VHF high band a lot, both conventionally and some WISCOM. There are some digital modes used in the 150-154 MHz area. It is way different than say 10 years ago. I know there are still some licensees for the taxicab radio service. There is a log hit or two for some of the services, but I really didn't hear nearly as much taxicab voice like I did years ago.

-UHF from 450-470 is clearly dominated by digital modulation. There are a LOT of Capacity Plus systems and lots of other stuff, too. Sure th ere is some analog activity, but digital dominates and MOTO TRBO dominates that around here. Like I said in an earlier post, there is some NXDN, but MOTO TRBO is the king. Again, with UHF, I recall hearing quite a bit of analog FM voice from taxicab users years ago, but that has moved to non-voice systems.

-800 Mhz seems to be a lot of ARMER and some other multi-channel trunked systems. Now that I think of it, I haven't heard any analog 800 MHz locally for a while. Obviously are some analog mutual aid repeaters that can get used, but they don't get used a lot. I remember hearing Rainbow Taxi a lot years ago on 800 MHz.

Radio procedures on the various frequencies are often interesting. I recall a user recently asking, "Hey, Willie, do you got your ears on?" It gave me a flashback to the CB radio craze 40 years ago!

Some agencies seem to have gone to using first names. I guess it works, but it still sounds very unprofessional to me, even if it is the Xxxxxx Public Works channel.

Fire service, be it paid, full time or part time, rarely seem to wait for acknowledgement from the communications center before talking. Maybe it is better in other places, but the typical scenario I hear is the fire service is pages, most of the suburban and rural fire departments and as have the crew for the rig, often a four person minimum, someone grabs the microphone and just gets on and talks.

I have pretty much always preferred that the field units simply announce their call-sign or call-sign and the comm center they are calling AND THEN WAIT FOR ACKNOWLEDGEMENT BEFORE TALKING! Yes, I get how they are an emergency service, but so are police and paramedics. Medic rigs typically would say something along the lines of, "Medic 41 to East Metro Control" and then wait for the response. That way the person on the other end is ready to give them their attention.

Law enforcement units typically are more disciplined and professional too. For example, you might here the following, "SP526 Metro." Then, when they are ready, the Comm Center says, "Metro SP526, go ahead." Then the conversations continue.

I will say, though, that sometime back I have heard police comm centers simply air the call and hope a field unit caught it. In this day and age of accountability, vicarious liability, etc. I thing it would be very risky for a comm center to operate that way. That IS how some of the taxicab dispatchers sounded like years ago, though. Sometimes it was an almost constant stream of locations and the cabs on the mobile frequency, not repeated, VHF high band acknowledged the fare.

And, speaking of practices of an era gone by, does anybody here still remember when Saint Paul Police and Hennepin County Sheriff's Radio would, temporarily, disable the repeater if a filed unit wanted to pass traffic, but didn't want everybody listening to the repeater output to hear it. Does anybody still remember some other agencies using an alternate channel or system for "sensitive" traffic? Some used their public works channel or Ramsey County Coop or what-have-you.

How many here can still remember Minnesota State Patrol on VHF low-band? Or, when they went to VHF high-band, who remembers when some of the districts didn't use a repeater for the mobiles or only did it by shift? Who remembers the Motorola VHF or UHF PAC-RT stuff? MSP used it here. The troopers had a UHF portable that communicated with the equipment in the squad that was then broadcast on VHF high band. Does anybody else here still remember places talking "cross-channel"? One squad talked on their own main or car-to-car channel and monitored the other agency on a scanner. Conversely, the other squad did the same. They didn't have to use MINSEF.

What other supplemental radio systems are you hearing agencies use? If I recall correctly, Eden Prairies has their own APCO P25 system, in addition to ARMER. Are they having an additional mobile installed? Do they carry a second portable? Does anybody still hear conventional analog used to supplement ARMER? Finally, are you seeing ANY squads that still have a CB radio or scanner in them here in Minnesota? I assume Airport PD has an aviation mobile in their squads.

 

[ofd8001]

Fire service, be it paid, full time or part time, rarely seem to wait for acknowledgement from the communications center before talking. Maybe it is better in other places, but the typical scenario I hear is the fire service is pages, most of the suburban and rural fire departments and as have the crew for the rig, often a four person minimum, someone grabs the microphone and just gets on and talks.

Firefighters around here could be better about being recognized before transmitting a message. Sometimes it's impatience, perhaps not paying attention that a transmission may be in progress or can't wait to be answered because of trying to give patient care.

How many here can still remember Minnesota State Patrol on VHF low-band? Or, when they went to VHF high-band, who remembers when some of the districts didn't use a repeater for the mobiles or only did it by shift? Who remembers the Motorola VHF or UHF PAC-RT stuff? MSP used it here.

When I was growing up in Minnesota, the SP was on VHF low and there wasn't enough money to get a scanner for that band. That was back when Minneapolis PD was on VHF high. On the VHF high end, I think even in the most remote parts of the state, like Thief River, they never had repeaters until the metro area migrated and they used some of the abandoned repeaters.

Around hear the Kentucky state police still uses the PAC-RT kind of configuration. Years ago, our fire department used something like that for a while to get around buying UHF portables for medical communications. We'd have a UHF mobile in a vehicle that was set to one of our VHF channels (we were on VHF then). If we needed to talk to EMS (on UHF) we'd go to that VHF channel and do out thing.

 

[fwfdengine2]

Fire service, be it paid, full time or part time, rarely seem to wait for acknowledgement from the communications center before talking. Maybe it is better in other places, but the typical scenario I hear is the fire service is pages, most of the suburban and rural fire departments and as have the crew for the rig, often a four person minimum, someone grabs the microphone and just gets on and talks.

On the HFMAIN "bullet transmissions" are the preferred method of communication by dispatch. You would give a "non-bullet transmission" and assure you have the dispatchers attention when giving a size up for an IDLH (Immediately dangerous to life/health) situation.

 

[ofd8001]

What is meant by "Bullet"?

 

[fwfdengine2]

What is meant by "Bullet"?

Bullet transmission example, "Brooklyn Park Engine 3 enroute"

Non-bullet transmission example, "Dispatch Brooklyn Park Engine 3" The dispatcher would then reply and Engine 3 would give their message.

 

[JASII]

On the HFMAIN "bullet transmissions" are the preferred method of communication by dispatch. You would give a "non-bullet transmission" and assure you have the dispatchers attention when giving a size up for an IDLH (Immediately dangerous to life/health) situation.

That makes sense. I would say that is pretty consistent with what I have heard on some other systems, too. For example, say squads are en route to a personal injury accident. When they arrive, they simply announce "2138 arrival." If it gets much longer than that, they are inclined to wait for acknowledgement.

 

[ofd8001]

That's exactly how it is done around here - police, fire and EMS.

 

[fwfdengine2]

If I recall correctly, Eden Prairies has their own APCO P25 system, in addition to ARMER. Are they having an additional mobile installed? Do they carry a second portable?

Police/Fire use ARMER primarily and have the EFJ system as a backup. Schools and city departments (streets, public works, etc.) use the EFJ system. Mall Security uses the EFJ system as well and has a soft-patch to ARMER.

 

[KA0XR]

Related question for any long time MN State Patrol listeners: How did reception/transmission range of SP VHF lowband back in the day compare to the range they got on VHF highband (42 MHz vs. 155 MHz direct wave)? From my research even back in the late 70's just about every MN public safety agency other than the SP was on highband.

I'm relatively new to scanning and only started listening at the end of the SP highband days. I have old maps from Monitor America of both the lowband and highband radio systems and a few tower sites were indeed added when SP converted to HB. However, I have also read about 3000 watt LB base stations being used once upon a time unlike on their HB system, which would have likely required fewer towers. Perhaps full statewide coverage was only implemented as part of the conversion to highband ? Just curious for any insight or memories on which SP VHF radio system regularly "traveled further" or if they were generally equal in strength since they were using the same sites/towers.

I miss the base->mobile HB days when you could hear the dispatcher on the base frequency then switchover to the input frequency to try and hear the mobile station and associated Motorola squawk.

 

[JASII]

Related question for any long time MN State Patrol listeners: How did reception/transmission range of SP VHF low band back in the day compare to the range they got on VHF highband (42 MHz vs. 155 MHz direct wave)? From my research even back in the late 70's just about every MN public safety agency other than the SP was on highband.

I'm relatively new to scanning and only started listening at the end of the SP highband days. I have old maps from Monitor America of both the lowband and high band radio systems and a few tower sites were indeed added when SP converted to HB. However, I have also read about 3000 watt LB base stations being used once upon a time unlike on their HB system, which would have likely required fewer towers. Perhaps full statewide coverage was only implemented as part of the conversion to highband ? Just curious for any insight or memories on which SP VHF radio system regularly "traveled further" or if they were generally equal in strength since they were using the same sites/towers.

I miss the base->mobile HB days when you could hear the dispatcher on the base frequency then switchover to the input frequency to try and hear the mobile station and associated Motorola squawk.

I started monitoring in the 1970s when I bought my first crystal scanner. I sort of felt a little bit mis-led when I bought it, too, because it was an Electra Bearcat III that used 10.8 Mhz IF crystals. The newspaper advertisement listed it is capable of VHF low and and VHF high band. What I didn't know, until after I bought it, was that although it was capable of VHF high band by simply installing the correct crystals for the frequency you wanted to receive., you needed an additional module to add VHF low band reception.

Nonetheless, most of what interested me then was, indeed, on VHF low band, with the exception of the Minnesota State Patrol. Despite my initial disappointment with the additional cost of a VHF low band module, I made the most out of listening to what interested me on VHF high band. As my interest in radio communications grew, I decided that rather than spend money for a module for a crystal scanner, I would simply save my money for a programmable scanner.

The choices back then for a programmable scanner were few. You had the Bearcat 101, which involved programming by a series of switches. Tennelec had one that used a card that was inserted for programming. The Electra Bearcat keyboard programmable had 10 channels and the Regency ACT-T16K, which I ultimately bought, had 16 channels.

The earliest keyboard programmable scanners, if I recall correctly, had VHF low band, VHF high band and UHF. The 800 MHz band was not in scanners yet. I could do okay, with a back of set antenna, listening to VHF high band frequencies if they used a repeater and they were fairly close to me.

You asked, however, specifically, about the Minnesota State Patrol. I do remember the two frequency dispatch arrangement. The District car-to-car was on the "base" frequency. All and F-3 and F-4 the same. They were 42.880 and 42.820. A separate radio was used for MINSEF. Range was better on VHF low band, than it is/was on VHF high band, but it was sort of like comparing "apples to oranges." Here is why I mention that. In the past, VHF low band was not permitted to have "mobile relays" (repeaters). So, if you were using low band, it obviously has better distance characteristics than VHF high band.

However, portable radios really weren't, and aren't, very practical on VHF low band. Most troopers then did not have a portable radio. Yes, they did have a cache of portables available, but they were not issued routinely. I recall troopers checking out, with dispatch, so they knew where they could be reached. If you were at a restaurant and they needed you to leave for a call, they made a telephone call to the restaurant.

When the Minnesota State Patrol went to VHF high band, it was a huge improvement in many ways. The General Electric mobiles had several zones and all of the district's frequencies were programmed in. You didn't need to use 42.880 or 42.820 to reach a district outside of your "home" district.

That allowed use of repeaters. Each district varied somewhat on how they operated. Some ran "full repeat" during certain times of the day and "two channel simplex" at other times. There were car-to-car repeaters that did not carry across the whole district, but essentially covered a "Station" area.

After they went VHF high band, some of the earliest portables to work with the VHF high band system were UHF. They were NOT General Electric, however. They were Motorola MX radios. There were only a couple of frequencies, however. A 453 and a 458 MHz, if I recall correctly. The squad received the VHF traffic and repeated it out on UHF. The cross-band repeater was limited, though. For example, if you went to MINSEF, you had to return to the car to switch it back to normal operation. The could use simplex, portable to portable on UHF. It was sort of cool, actually, because the car repeated what ever they were scanning on the GE mobile. So, if you drove by a crash scene, you might hear troopers talking to each other on UHF simplex and hear the car repeating the local sheriff;s office radio traffic, too.

The other thing that bears mentioning, too, is the ability with the GE, it may have been a Delta, to have local sheriff's office channels installed, with the permission of the sheriff's office, of course. So, you might hear a county air a grinder somewhere and before the State Patrol District Office could even air it, you might hear, "SP 261 Xxxxxx County, I copied the 10-52 and I am en route." It was a huge step towards better inter-operability.

It wasn't until some time later that additional satellite receivers were added throughout the state so that troopers could have VHF high band portables that worked without the need for a cross-band vehicle repeater.

One other thing I should mention is back when they were on VHF low band, there were some places that had a VHF high band link. I recall that the site that it linked to was VHF low band, but carried the traffic across 154.xxx or 155.xxx. The nice thing was, even though the links were directional, if you were within range of a VHF high band link, it allowed you to hear a lot more traffic. For example, I think Sandstone had a VHF high band link on 154.680. I was able to hear the MSP cars in the Pine County area rebroadcast. Shakopee had one, too. that carried traffic for District 2500.

Hopefully, that answered a least some of what you wanted to know about VHF low band usage for Minnesota State Patrol. Skip was obviously a problem back then during certain times of the year when certain atmospheric conditions occurred. By the time I was listening, they had added PL tones on the VHF low band frequencies. PL helped, but it doesn't make a strong signal received during skip conditions vanish. Also, keep in mind that DPL really wasn't common in public safety, at least not then and not around here. There are only about 38 EIS standard PL tones. So, if 42.540 was coming in loud and clear from California, there is a chance that it might even have the same PL tone as you main channel. And, to further reduce the number of commonly selected PL tones, most seemed to avoid using tones below 100.0 Hz and above 200 Hz. So, that really means that less than 38 tones were actually in common usage in public safety!

I must say, in retrospect, it was a very different time to listen. In many respects, not at all like today. Today, all of the State Patrol is dispatched out of Water's Edge (Roseville) and Rochester. Back then, each district had it's own dispatch. It was later that east and west moved to Roseville. Golden Valley identified as such. Oakdale identified as Saint Paul.

I should mention, too, that it wasn't unheard of to hear K cars on VHF low band. I hear them much less often, now, on the radio. I don't recall many "other agencies" on VHF low band, but when they were on high band, you could hear all sorts of other, miscellaneous units chek in from time to time. Let's see, I recall FBI, United States Marshal, Minnesota State Fire Marshal, BCA agents, DOT Haz-Mat, etc. back then. It was an interesting time!

I should mention, too, that having an external antenna, particularity for monitoring VHF low band, was really important. I actually modified a 1/4 wave CB base station antenna for VHF low band VHF high band. I could really hear a long ways away with it. During skip affecting VHF high band, something common like 155.595 would be almost non-stop. I would hear Duluth Police, then when they stopped talking, I could hear Dakota County Sheriff and if both stopped talking I could often hear an agency or two in Wisconsin. Listening during skip conditions was a "whole different ball game", so to speak!

 

[stmills]

Analog Vhf scanning was definitely a different world compared to ARMER today. Skip made it fun to identify co channel users. To go on a couple of your SP items - the beat / area repeaters were really interesting- usually were a separate pl input from the main channel - the 2 that stick out in my mind were the “Tunnel “ covering inside the Lowery Hill tunnel and 2600 had a tower in Northern Anoka county that I seemed to get better beat coverage from versus the main.
VHF MT1000 replaced the UHF MX300s(453/458.2500?) with PACRTs in the Metro are 1990 or 91, but did not move statewide in some districts until the 2000’s. If I recall correctly the Metro VHF Equipment was reallocated outstate when the Metro Went 800mHz.

 

[omgitstony]

Police/Fire use ARMER primarily and have the EFJ system as a backup. Schools and city departments (streets, public works, etc.) use the EFJ system. Mall Security uses the EFJ system as well and has a soft-patch to ARMER.

And the EP TGs as well as the ARMER TGs are programmed into the same portables/mobiles. PD/FD switches over to talk to the EFJ system users sometimes and can use coordinator/event TGs for bigger events (schooner days/4th of july/etc).