Cell system failures in CA fires

[mmckenna]

What is a TIS transmitter?

Travelers Information Stations. Basically low power AM transmitters that are used to broadcast travelers information, road info, emergency info out to the public. Common in some national parks, airports, big cities. Travelers' Information Stations Search

 

[W5lz]

... okay, thanks.

 

[bharvey2]

As well as the dreaded "backhoe fade" issues.

That's probably more common.

 

[AK9R]

What is a TIS transmitter?

Travelers' information station - Wikipedia

en.wikipedia.org

 

[mmckenna]

Underground fiber isn't 100% immune to damage either. I've seen insulation melt away on underground cabling too when a fire above it is hot enough.

This is a photo from a few years back.
We have quite a bit of fiber running to different sites and to different carrier POP's. This was part of a 60 mile run that passed out of town to another area to tie into Level3. In a storm, a tree came down, snapped a power line. That hit the messenger, which is grounded. That sparked the fiber jacket up and it burned until the electric utility showed up. That section of fiber was obviously replaced...

 

[a417]

What is a TIS transmitter?

Traffic Information Services.

"TRAFFIC INFO ON 1610AM" etc..

 

[bharvey2]

This is a photo from a few years back.
We have quite a bit of fiber running to different sites and to different carrier POP's. This was part of a 60 mile run that passed out of town to another area to tie into Level3. In a storm, a tree came down, snapped a power line. That hit the messenger, which is grounded. That sparked the fiber jacket up and it burned until the electric utility showed up. That section of fiber was obviously replaced...

Exactly why redundancy is key. The saying "Two is one and one is none" couldn't be more true. If it can be "FUBAR"'ed, expect it to happen. And the second part to that is: It can ALWAYS be "FUBAR"ed. I've run across people that I think stay up late at night thinking of ways to break things. Combined with nature and Murphy and the battle never ends.

 

[wa8pyr]

Most of the cell sites have no more than 8 hours of battery backup and most don't have generators. Getting a few hours out of them is pure luck. Battery maintenance isn't always what it should be.

To make matters more interesting, only common carriers were/are required to have generator backup on their cell sites. In the early days of cellular, there were two carriers per market, one wireline (a common carrier, like AT&T) and one non-wireline and not common carrier. I haven't really kept up on the changes (although I should), but to this day most of the cell sites I drive by don't have generator backup; all most of them have is a big Hubbell connector on the side of the equipment cabinet so a mobile generator can be plugged in if they happen to shake one loose to haul in.

 

[bharvey2]

To make matters more interesting, only common carriers were/are required to have generator backup on their cell sites. In the early days of cellular, there were two carriers per market, one wireline (a common carrier, like AT&T) and one non-wireline and not common carrier. I haven't really kept up on the changes (although I should), but to this day most of the cell sites I drive by don't have generator backup; all most of them have is a big Hubbell connector on the side of the equipment cabinet so a mobile generator can be plugged in if they happen to shake one loose to haul in.

The company I work for hosts a number of cell providers on their properties. I've not seen much in the way of long term battery backup and as you mentioned, they're wired to accept a portable generator. No permanent generators have been present.

 

[mmckenna]

if they happen to shake one loose to haul in.

And that's what we've run into in the California PG&E Power outages. If we know they are coming, we can request a trailerable generator from the carriers.
IF they have one, they'll bring it.
IF they have someone to bring it, that is.
The few generators they have are stored at their MSO about 50 miles away over the mountains.
That means we don't always get one.

I'm working as part of a larger project to put a generator at the site for them as well as some of our needs. But it keeps getting "value engineered" out of the project. What it comes down to is that people love their cell phones, and think they can rely on them in an emergency, but won't put a whole lot of effort into it.

At our sites, AT&T and Verizon have shore power connections. One of the T-Mobile sites does, but that's only because they inherited it from AT&T. Sprint has no connections, unless you open the breaker panel and tie a generator in that way.

Cell carriers really don't care about this stuff, at least not as much as people think. They'll sell you on "emergency" use, but they don't back it up. In a way, I'm sort of happy to see this happen. Not only has it sold more radios, but it's also forced people to think about the issue.

 

[slicerwizard]

What is a TIS transmitter?

TIS transmitter - Google Search

 

[wa8pyr]

Cell carriers really don't care about this stuff, at least not as much as people think.

Only insofar as it affects the profit margin.

They'll sell you on "emergency" use, but they don't back it up. In a way, I'm sort of happy to see this happen. Not only has it sold more radios, but it's also forced people to think about the issue.

True, but in many case that's about all that will happen, thought and talk. You're right, people are in love with their devices and are convinced they can count on them in an emergency, but they can't really; it will take thought, talk and action to get something done. Ultimately, until the carriers are forced by FCC regulation to outfit their sites with proper backup power, it won't happen too much except in critical locations (and metro areas where most of the subscribers are).

 

[MTS2000des]

Yep! I say this daily! A site is only as good as it's backhaul, at least in the cellular world. Most all sites backhaul with contracted fiber companies. It's the most cost effective and it provides the necessary bandwidth.

LMR, ham and broadcast transmitters burn at the same temperatures and are just as useless if they don't have power.
Disasters like these fires show NOTHING is fail safe.

 

[12dbsinad]

LMR, ham and broadcast transmitters burn at the same temperatures and are just as useless if they don't have power.
Disasters like these fires show NOTHING is fail safe.

Of course nothing is fail safe. Some technologies are just better than others in disaster situations, in this case, LMR. You can do things with LMR to get some sort of comms up and running on a very temporary basis that you simply cannot do with LTE based systems. If you don't believe me, go work tornado alley like I've done. The other ailment is no direct mode yet and if so, very low power operation from the handsets even so.

 

[MTS2000des]

Of course nothing is fail safe. Some technologies are just better than others in disaster situations, in this case, LMR. You can do things with LMR to get some sort of comms up and running on a very temporary basis that you simply cannot do with LTE based systems.

A complex trunked radio system, such as the one I am involved with, are just as prone to being destroyed and complex to restore (if not more so) than commercial LTE if destroyed by a natural disaster such as fire, flood, hurricane, etc. Sure, the failure modes such as site trunking, fail soft, and standalone resources offer a more graceful fallback, but restoration paths are similar: equipment replacement, staging, etc are just (if not more) costly in complex systems with multiple sites.

If you don't believe me, go work tornado alley like I've done.

I live in one of the most tornado prone counties in my state. Been through 3 personally. My agency has supported two tornadoes in 2019 including an EF-2 in February that wiped out all communications in one rural county including LMR. Oh, FWIW, First NET had a SATCOLT on the scene within 4 hours. VZW showed up the next day. Because the agency didn't have funds, and LMR shops were not in the area, it would be weeks before their conventional VHF repeaters were restored. In the meantime, we sent a COM-L/COM-T and a RapidComm trailer and got some on scene LMR up and running, but the majority of wide area took place on LTE (FirstNet/AT&T commercial and Southern Linc LTE).

 

[nanZor]

mmckenna - I'm totally with you on this with a few notes

We already have tools to do this. It is AM broadcast radio. FM broadcast radio. Broadcast TV stations, all using the EAS system. Then we have NOAA alerts, which can handle EAS and other localized alerts.

People should have a battery powered AM/FM radio and ideally, a radio with NOAA capability. Not expensive. Most people have them in their car, but forget how to use them.

Which is one reason I keep a CCrane EP-PRO, which has modern internals, but retro-operations. Nothing to figure out when in a panic. Or as a handout to my non-radio savvy neighbors in a panic who isn't going to drill-down some menus. D-powered or AA with holders. simple.

Propogation - if it is bad enough that the locals are down, at least one can wait until nightime. Example: If there was a major emergency in L.A. to where even the locals or nearby stations are down or weak, I can still hear San Franciso, Oregon, or other out of state flamethrowers with no problem. If there was an agreement to temporarily broadcast local L.A. information from those out of state flamethrowers, that might help alleviate lack of local reception and get the word out. The locals might be willing to put up with detailed emergency announcements.

Kind of a reciprocal agreement thing - if San Francisco got into a heap of trouble, have KFI in Los Angeles broadcast the necessary detailed emergency information to that community, simple because there is a great chance they can hear us with a common AM radio.

Back when the solar cycle was good, this could have even been applied to shortwave. Let's say the west-coast got hammered badly. Radio Australia on 11780 was a flamethrower and easily found on the cheapest of shortwave portables. I always thought that if some sort of agreement could have been reached between the US and Australia to temporarily broadcast detailed information to our community, how helpful that might be. And of course if the US still had shortwave transmitters, our Australian friends dealing with wildfires might have welcome emergency info coming from this side of the pond. This is just an example, and of course wouldn't work today with the poor sunspot cycle.

But yes, I'm totally in agreement with using AM radio as a fallback - which could be enhanced with inter-state agreements to broadast detailed community information to each other in times of need.

 

[mmckenna]

mmckenna - I'm totally with you on this with a few notes



Which is one reason I keep a CCrane EP-PRO, which has modern internals, but retro-operations. Nothing to figure out when in a panic. Or as a handout to my non-radio savvy neighbors in a panic who isn't going to drill-down some menus. D-powered or AA with holders. simple.

Propogation -…...

Yep, I was here for the earthquake in 1989 that wiped out a lot of stuff. AM radio was what we all went to. KGO, the big clear channel 50KW station in SF went down for a bit, but were able to get back up and running shortly after. They cover a most of Northern CA really easy.

And let's not forget NOAA weather radio.

Lots of options out there.

 

[GTR8000]

FirstNet/LTE/5G/etc. is not going to replace LMR anytime in the near future. Perhaps in a few decades, but LMR is going to be around in its current form for many, many years to come. I'm often puzzled by the proclamations from some "industry professionals" who insist that FirstNet and similar LTE networks are going to make LMR irrelevant within the decade. Nonsense.

It won't be that cut and dry. What you're going to see is a lot of integration between LMR and LTE, as MSI is already rolling out with Critical Connect and the APX NEXT. LMR will remain the backbone of the whole operation, providing the robustness and strong in-building coverage public safety requires, while LTE networks like FirstNet and Verizon's private public safety core will supplement that coverage when linked to the LMR system.

The bottom line is that these LTE sites will never achieve the same robustness and fault tolerance as a traditional LMR site. Ultimately, you are still at the mercy of a private corporation (AT&T or Verizon) when you're using LTE, as opposed to the vast majority of LMR systems which are maintained directly by the local/city/county/state public safety organizations and related apparatus. If an LMR site goes down, there is normally a contingency plan in place and personnel to deal with the situation in a timely fashion. Public safety LMR sites normally have battery and/or generator backup to keep a site running for an extended period of time. The same is not necessarily true for LTE sites, which are built out to less of an assurance of continuous operations standard.

LTE certainly has its place in the world, and will continue to be an important piece of the puzzle when combined with traditional LMR...but it's nowhere near ready for prime time as far as a full blown replacement for LMR.

 

[nanZor]

My apologies if this should really be another thread topic - ludicrous to contrast AM to modern technologies but ...

Cons:
Only usable at night if local station(s) is down
Stricken listeners would have to know to tune to the alternate frequency.

Cooperating "sister station" broadcasting non-regional specifics to it's sister audience, would need special announcement techniques so as not to panic the regular local listeners.

Pros:
Seemingly no cost to implement, other than coordination and a reliable way to get info TO the helping station.
Sister station not affected, so fault-tolerance and robustness is not an issue.

Options:
Allow for temporary power and pattern changes if possible to helping sister station.

Sorry - jumping out now, but it was brought up ...

 

[12dbsinad]

A complex trunked radio system, such as the one I am involved with, are just as prone to being destroyed and complex to restore (if not more so) than commercial LTE if destroyed by a natural disaster such as fire, flood, hurricane, etc. Sure, the failure modes such as site trunking, fail soft, and standalone resources offer a more graceful fallback, but restoration paths are similar: equipment replacement, staging, etc are just (if not more) costly in complex systems with multiple sites.

You're over complicating things. First and foremost, nobody is going to restore any system to full capacity and capability in a few days. We are talking about initial extreme band-aid restore of partial communications. During and immediately following a major disaster, the focus of communications is on search and rescue as well as hazard mitigation. Your radios should number 1 have a zone of nationwide interop channels. Analog, simplex, and repeated no matter what band you are using. That's why they exist. If you don't, you should. At that point any base station not destroyed can become a communications center for a given area. Add many of these that can relay to each other over the air and you have successfully created a repeater system. Simple and effective with zero infrastructure. These are the things you're NOT going to do with a little LTE cellphone.