259 replies to this topic

[Bingo]

Does the scanner provide you the info to allow you to chase ambulances?

[eseedhouse]

Does the scanner provide you the info to allow you to chase ambulances?

If one was so minded. Ambulance, Fire and Transit are broadcast in analogue narrow band FM, so a quite cheap scanner would likely be enough. The cost goes up a couple of hundred bucks if you want to decode digital.

Locally, CREST is a "trunking" system which allows many users to share a few antennas and frequencies. For Crest you would need a scanner that can do trunking, because conversations can hop between frequencies and that adds a few bucks. There are also a few LTR trunking systems in town which are all analogue, and all commercial. Totem towing is on one of them so that might give you some leads too.

Although the fire departments all seem to have supplemental repeaters that rebroadcast trunk traffic on a single frequency.

I don't know how data is pushed through to police vehicles. They speak of having documents copied to them but there are no talk groups I know of that contain that data. In any even it is very likely sent as IP packets and also encrypted. Not decodable with any commercial scanner that I know of.

There is a database of Canadian and US frequencies maintained at the "Radio Reference" website (http://www.radioreference.com/) and my GRE-800 and the Uniden Home Patrol come with free access to this database which is refreshed weekly. If you have some bucks the HP is probably the best bet because you can just enter your postal code and it will start to scan local frequencies including, for Victoria, the CREST system. But the HP is out of my price range in Canada at about $600.00.

The GRE was $450 plus shipping and HST. GRE sells a similar scanner without the P25 decoding for a couple of hundred bucks less. No one I know of sells scanners locally anymore so you have to get them via the post. I got mine from Radioworld (http://radioworld.ca/index.php) but Durham Radio (http://www.durhamradio.com/) also ships them and you can always order them from the states when the Can$ is high.

Also a lot of newer scanners are darned hard to program on their own, but you can generally get freeware that will let you do it more easily. It took me a couple of weeks to figure out my first scanner, a Uniden 346XT and the manual that came on a CD with the scanner was just horrible.

The new GRE and Uniden scanners come with SD chips that can hold a couple of gigabytes of data and the scanners can be programmed to record to them for later listening.

Also a lot of big cities in the states have live web audio feeds provided by scanner owners so if you live there you wouldn't even need to buy a scanner. I know of none in B.C. though. The RadioReference web site cited above carries many of these live feeds.

If you really want to ambulance chase there are also mobile scanners designed to be mounted on your dashboard and powered from you car's battery.

[sebberry]

I'd be wary of buying a scanner for fear that VicPD flips the switch to encrypt everything.

[eseedhouse]

I'd be wary of buying a scanner for fear that VicPD flips the switch to encrypt everything.

Very unlikely in the near future. Police agencies that tried to do this in the USA ran into a lot of political problems about openness and mostly rolled back to unencrypted P25 due to the public outcry.

In any event there are hundrds of analogue fm and am frequencies around town. Aircraft communication is via AM (for good technical reasons) at around 118-133 mhz and the maritime bands are all standard narrow band fm. Of four trunking systems in and around Victoria only one (CREST) even has digital available.

Besides secure transmission is readily available to the police via cell phones when they really need confidentiality. You can't buy a scanner to receive cell frequencies in Canada or the USA unless you can prove you are a government agency.

P25 encryption on the other hand, is problematical and there are several well known ways to defeat it which I will not go into here for obvious reasons, but you can buy magazines at Chapters that will tell you all about it and probably there's an article on wikipedia that will explain why.

...In fact a quick check shows just such an article at http://en.wikipedia....cryption_lapses

There are other digital systems that are less prone to P25's vulnerabilities but here in Victoria that would mean putting out many million dollars to replace CREST and all the motorola handhelds the agencies that use it carry.

Also encryption damages cross-agency communication which became an important national security consideration in the USA after 9-11 when the police couldn't talk to the firemen and the ambulances couldn't talk to either of them. In fact that was one factor that provided the impetus to develop the P25 digital standard in the first place.

[mc9]

Also encryption damages cross-agency communication which became an important national security consideration in the USA after 9-11 when the police couldn't talk to the firemen and the ambulances couldn't talk to either of them. In fact that was one factor that provided the impetus to develop the P25 digital standard in the first place.

Thanks for the information, it is really interesting. Really sad though.

[Bingo]

Very unlikely in the near future. Police agencies that tried to do this in the USA ran into a lot of political problems about openness and mostly rolled back to unencrypted P25 due to the public outcry.

In any event there are hundrds of analogue fm and am frequencies around town. Aircraft communication is via AM (for good technical reasons) at around 118-133 mhz and the maritime bands are all standard narrow band fm. Of four trunking systems in and around Victoria only one (CREST) even has digital available.

Your knowledge of radio systems is interesting. What do you think of the Crest radio system? Is it now working properly?

Crest cost the city $17 million back in 2003, was repaired in 2007 for 10.6 million and will likely be outdated within 10 years.

[eseedhouse]

Your knowledge of radio systems is interesting. What do you think of the Crest radio system? Is it now working properly?

Well, they seem to have addressed the problems mostly by putting in more repeaters, and maybe upping the power output. As well as Camosak Manor and the CRD building, they have antenna farms on Mt. Newton, Mt. Douglas, Mt. Helmcken, Mt. Macdonald, Mt Bruce (Saltspring Island), Mt. Parks, and Mt. MacGuire. Basically you can get five bars with a tiny rubber ducky antenna anywhere around town. But if a building has a metal frame and metal sidings it's pretty hard for any radio to penetrate.

They currently cover a wide area from Saltspring and some of the gulf islands to as far as Shirly. RCMP have moved onto CREST though they

The one on the CRD building is pretty recent addition and overloads my scanner anytime I get close to it.

They use VHF frequencies up around 150 mhz, just above the 2 meter ham band, and I've heard that some police think it would do better on the UHF frequencies up around 800 mhz. But that isn't really right, because radio waves penetrate better at lower frequencies. They do use 800 mhz in Port Angeles and Bellingham, but they are not using trunking systems there. The commercial LTR type trunking systems in Victoria are up around 400 mhz but they are all analog.

P25 digital is actually a pretty shaky protocol with poor error correction and the voice quality is poorer on my scanner than the analogue talk groups. The digital channels tend to sound "phasey" on my scanner. Just about any manufacturer tends to add their own proprietary features to P25 so their own portables (in this case Motorola I believe) will likely more reliable than a five hundred dollar scanner since they are purpose built for the system.

The dispatchers often ask for repeats on things like license plate numbers, and they call the odd scrambling that occurs from time to time "getting bonked". Generally digital works until it suddenly doesn't, whereas analogue degrades faster but you can still generally hear the words underneath the hiss with a weak signal.

Crest cost the city $17 million back in 2003, was repaired in 2007 for 10.6 million and will likely be outdated within 10 years.

I imagine they will keep it going as long as possible but will eventually "reband" to UHF frequencies which, while they don't penetrate walls as well, are less subject to inter-modulation interference from high power transmitters near their operating frequency. There's more room to spread the channels out at the UHF end than down on VHF. That would only mean reprogramming the frequencies for scanner users.

[Baro]

People who monitor and even record these communications act as invaluable watch-dogs. There have been many cases of police misconduct and corruption caught on their own radios.

When ever law enforcement wants to hide their communication, or make it illegal to photograph or record them it's nothing to do with their crime fighting abilities and everything to do with hiding their potential corruption and incompetence.

[eseedhouse]

People who monitor and even record these communications act as invaluable watch-dogs.

Oddly, the CREST system seems to have started advertising - I heard an ad extolling their virtues on CFAX just as I was getting up this morning. The add touted the fact that they now have a website: http://www.crest.ca/

The web site uses low contrast and teensy tiny fonts, apparently to keep us older folks with weakish eyes away! Fortunately Firefox lets me enlarge it to the point where it is readable.

[eseedhouse]

In their "FAQ" page they claim that "The system is also designed to move towards an open standard of telecommunications when the technology becomes available."

Not entirely sure what they mean by this.

[eseedhouse]

BTW I've seen Crest ads on BC transit buses now too. I bet there's a union contract expiring soon or something.

I don't know if CREST staff is unionized, but I am pretty sure that they would be, likely by CUPE but also possibly by BCGEU. If I had to bet I'd bet they'd be in CUPE local 50 which, I believe, has already reached a contract for the next few years. But I don't for sure who their union is, or if they actually are organized.

Most CUPE locals that negotiate with the GVLRA have already reached Memorandums of Settlement and from what I have heard the settlements are in the range of 2% per year, slightly under the current inflation rate.

I believe Victoria city hall has already ratified (local 50) and I know that there will be a ratification vote for Library workers on Sunday. I plan to be at that because although retired I still have an honorary membership, so I will know more next week. The 2% is not all in take home pay, but the overall costing is apparently about that. But I will not know the full details until after the Sunday meeting.

[pontcanna]

CREST is now streaming at:

http://ltr.tac9.ca:8000/crest.m3u

The parent site is http://www.scanbc.co...title=Main_Page

[sebberry]

Not quite sure I follow how that one works.

Does it jump from conversation to conversation?

[Sparky]

^^ That's cool. It would appear that people with scanners upload the audio traffic through "Scan BC" web portal.

Seb, it appears to just stream as it happens, so some dead air until a transmission.

[sebberry]

Seems to hop around a lot, one minute it is a Saanich fire, the next it is something in Langford.

So I'm guessing this online one is just a scanner that hops frequencies? If I was to listen with a handheld scanner, would I be able to listen to one conversation/incident in its entirety?

[Sparky]

I think it is for "greater Victoria". I just heard a conversation about an incident on Sooke Road.

Maybe the guy that is uploading receives more channels than Crest?

[sebberry]

I'm enjoying listening to this. Depending on how they work, I might have to invest in a scanner

[Lorenzo]

CREST is now streaming at:

http://ltr.tac9.ca:8000/crest.m3u

The parent site is http://www.scanbc.co...title=Main_Page

Not working for me. All that comes up is the Widowws Media Player and nothing else.

[sebberry]

Odd - sometimes there are long silent pauses, sure that's not it? Does Media Player show "CREST" anywhere on the screen?

[Lorenzo]

Working now after a few tries. Thanks.