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PostPosted: Thu Oct 30, 2008 3:10 pm 
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Looking at the KC system, there's long been two empty sites--the tunnel. So I ventured down there today with two scanners, and here's what I found:

868.225 is the control channel for the North end of the tunnel. Site 004.
853.4875 is the control channel for the South end of the tunnel. Site 005.

Here's whats interesting, to me at least: 868.225 is the control channel for both sites 002 (Apple Cove) and 004 (Metro tunnel North). I've been unable to confirm site 002 myself. That's a clever use of the spectrum if you ask me. I just looked in the database here and it looks like someone already discovered this, so it's old news.

I did find a couple of talkgroups that weren't in the database here:
60304 - Used in all parts of the tunnel. All Sam units. I talked to an orange-vested platform-lurker and found out it's Channel 1, and it's the one that "all the guards use". The channel doesn't have a name, but they do have access to more than one channel. It's also used by someone just south of the tunnel. While waiting at the International District tunnel; I heard one of the Sam units announce to another that "213" was headed his way. 213 was a Chevy Express (or GMC Savanna) but wasn't one of the Metro supervisors. It was some sort of work vehicle. It traveled in the tunnel between two coaches. Users also call by "Officer X" in addition to "Sam X". There's also some sort of "I 90" that has to do with Pioneer Square station. I don't know where their dispatchers are, but they're close enough where the rovers can break them (give lunches).
60648 - I only heard this on the North side; it has something to do with trains and/or light rail. They referenced a Henderson something, lot I believe. Also, someone was moving something into a pocket track.

Also, voice channels for North: 866.1625, 855.9875, 853.6125. South: 858.9625. I don't have a tap on any of my scanners so I can't run any of that cool software.

60304 may be repeated in one or more tunnels; I caught traffic on 458.5125 and heard the same traffic from an orange vest's radio. PL of xxx.8; the 396 blinks on PL search making it hard to read.

Coverage split is University Street station northward; Pioneer station southward. South provides decent coverage between Pioneer and University. The signal also bleeds into Nordstroms a little bit, and just barely into the Convention station.

A few other random notes:
853.4625 is a control channel; I picked up site 002. The channel was active for less than a minute once every 10-15 minutes.
868.4000 is a control channel for site 015. Loud and clear at International District station.
I picked up a lot of close call hits in the 900s when traveling between stations. They were all constant dead air; constant full signal.


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PostPosted: Thu Oct 30, 2008 5:22 pm 
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as for the D-Tap I can help if you want done a lot of em over the years. Also i would try the software with out it. with a little tinker time I can make my 996 use unitrunk with no D-Tap (when I originally purchased it back in the day I was too scared to f it up right away)

also the 900 is likely pager/DOT/MDT for the busses they all use a lot of communications with UW tracking systems driver MDT etc...

Since its a direct Cell off Seattle I never have heard any data in bellevue/snoqualmie obviously.

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PostPosted: Thu Oct 30, 2008 5:58 pm 
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I hadn't thought of doing it without the tap. Any hints on how to configure it?
SpudGunMan wrote:
also the 900 is likely pager/DOT/MDT for the busses they all use a lot of communications with UW tracking systems driver MDT etc...

Metro data is on 452.375 and 452.8; the signposts transmit on 49.83. I don't knowmuch about pagers; but why would they transmit dead air?


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PostPosted: Thu Oct 30, 2008 6:05 pm 
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Atomic Taco wrote:
the signposts transmit on 49.83.


Are you referring to the transmitters I see all over town, above bus stops etc...?

49.83?


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PostPosted: Thu Oct 30, 2008 6:25 pm 
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Atomic Taco wrote:
I hadn't thought of doing it without the tap. Any hints on how to configure it?

just plug it in like you would with a TAP but hint, download the old copy with the software oscilloscope then play with the volume on your radio and computer sound card, i have a sb audigy card and it works with just 3-4 min of volume tinkering. i plug into the MIC input.

the trick is then to watch the scope data, you want it max but no flatline on your scope.

then fire up the unitrunker and watch the fun...

Quote:
Metro data is on 452.375 and 452.8; the signposts transmit on 49.83. I don't knowmuch about pagers; but why would they transmit dead air?


I was just speculating, as obviously there is a TON of noise downtown, UW will always test things with metro buses and the downtown bus's are normally running some funky experiment. remember that most buses also have free wifi, and DOT also watches the busses which dont just stick to the published MDT 440's (I also seem to think about a year ago they dumped the 440mdt's for encrypted systems, as about a year ago the mdt.exe decoder wasnt working any more)

the dead air normally is either intermod or just a carrier for something that is out of FCC compliance. but for anything else there is a very large amount of equipment that is wireless in and around the tunnel without a direction finder work hard to say where its coming from.

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If I had an antenna, I would; but I can only transmit on 160 meters.
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PostPosted: Thu Oct 30, 2008 6:32 pm 
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N7QOR wrote:
Atomic Taco wrote:
the signposts transmit on 49.83.
Are you referring to the transmitters I see all over town, above bus stops etc...?

49.83?

I think so?? I just remember seeing this somewhere. I can't find it now, but somewhere there was an explanation of this system. Basically the bus gets an ACK from the signpost, and the bus sends its coach number and the stop number to the big database. I can't remember where all of the signposts are around me--the digital ones at least, but I know I've seen them. They're the regular signposts with the gray attachment on the top. There's a solar panel on the very top.


SpudGunMan wrote:
as obviously there is a TON of noise downtown, UW will always test things with metro buses and the downtown bus's are normally running some funky experiment. remember that most buses also have free wifi, and DOT also watches the busses which dont just stick to the published MDT 440's (I also seem to think about a year ago they dumped the 440mdt's for encrypted systems, as about a year ago the mdt.exe decoder wasnt working any more)

the dead air normally is either intermod or just a carrier for something that is out of FCC compliance. but for anything else there is a very large amount of equipment that is wireless in and around the tunnel without a direction finder work hard to say where its coming from.

The tunnel is silent. It's made of cement and does a good job of blocking most things out. That's why there are separate sites for the tunnels. Only the 48 and the 197 have WiFi; a couple of the Sound Transit routes have it. Actually, I don't remember the 48 having WiFi the last time I was on it, but they don't always have a WiFi coach serving every leg of every route. As to MDTs I've never seen the operators touch that gray box next to the money taker; I'm not even sure that's an MDT.


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PostPosted: Thu Oct 30, 2008 6:43 pm 
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49.830 is one of the old cordless phone freqs.

I think the antennas on those signpost things is smaller. Could be 450, but really looks like an 800/900 antenna.


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PostPosted: Thu Oct 30, 2008 7:15 pm 
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taco you left out part of my quote...

I said "I was just speculating"

there is no reason that 900 mhz isnt in use in units or has the ability to sneek into the tunnel (depending on where your at, near the mall for example there is ample chance). or simply is intermod of other systems. There is 700mhz licences's as well as 150 mhz licences attached to "tri-county" metro busses that could be in use for testing etc on any system. there is a lot of testing that could be in place for the new digital payment system (but think thats mostly 700)

your stats for Wifi on only two routes, i thought they were going to 50+ when they got done

when I reference MDT im not calling out the MDT that I assume your referencing to a Police car. MDT could be any system that provides data, i remember being able to decode the MDT data with to see route location data when they arrive etc from 3 years ago or so. (same things for the train systems in the area)

not to mention all the testing that UW is playing around with all the time on metro busses, DOT testing for traffic flow data etc etc....

I'm not speaking fact I was speculating, I haven't been on a metro bus for 5 years and haven't been in the tunnel since just before it closed years ago. Im not telling you your wrong Im just adding input.

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If I had an antenna, I would; but I can only transmit on 160 meters.
_____
DE K7MHI


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PostPosted: Thu Oct 30, 2008 7:22 pm 
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N7QOR wrote:
I think the antennas on those signpost things is smaller. Could be 450, but really looks like an 800/900 antenna.

The ones I remember look more like this:
Image

SpudGunMan wrote:
taco you left out part of my quote...

I said "I was just speculating"

My bad, I meant to clip that one like I usually do, but I got lazy.
SpudGunMan wrote:
your stats for Wifi on only two routes, i thought they were going to 50+ when they got done

Man I wish. The only routes I've ever been on with WiFi are the 197 and 577. And most of the time I check; my phone has WiFi.
SpudGunMan wrote:
when I reference MDT im not calling out the MDT that I assume your referencing to a Police car.

I understand; I just assumed that their little controller (it looks more like the thing you swipe your credit card through and then sign on the screen) was on the 450s with the AVL responder.
SpudGunMan wrote:
not to mention all the testing that UW is playing around with all the time on metro busses, DOT testing for traffic flow data etc etc....
http://www.its.washington.edu/its_software.html
SpudGunMan wrote:
I'm not speaking fact I was speculating, I haven't been on a metro bus for 5 years and haven't been in the tunnel since just before it closed years ago. Im not telling you your wrong Im just adding input.

And that's why the forums are here; so we can all yak about the frequencies we listen to


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PostPosted: Fri Oct 31, 2008 9:57 am 
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The small circular transmitters are indeed 400MHz range. They're part of a pilot program that Metro has going to deliver spoken information about whatever stop the transmitter is at to vision-impaired folk with special receivers.

If you look closely at the housing of one, you will find the frequency stamped into its factory data plate.

My guess is that the stuff coming out of them is raw digital data, and the receiver does the decoding into synthesized speech. I have not tried to confirm this as yet.

Happy listening.

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Bruce Lane, KC7GR
Owner, Blue Feather Technologies
Motorola programming and conversion service available. See http://www.bluefeathertech.com/rf.html
"Salvadore Dali's computer has surreal ports..."


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PostPosted: Fri Oct 31, 2008 11:33 am 
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kc7gr wrote:
The small circular transmitters...

Where? On the signposts?


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PostPosted: Fri Oct 31, 2008 1:11 pm 
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Taco, the Unitracker latest version has a "signal" mode which uses just audio output from the control channel. (You need a 1/8" audio cable from your scanner to the MIC input of the computer.)

Getting the mic levels is a bit tricky, but for the BC396T, I use audio volume #4 - which seems to work great. But of course, you need to configure your MIC inputs on the computer side as well.

You can see what the control channel is doing in real-time. I haven't found a FAQ yet, so I'm not sure what everything all means. If I understand the values, then you can see the Radio ID's of the radios keying up a specific talkgroup. There's a lot more data going on than just the audio output at that time. It's very handy to monitor talkgroup patches.

Perhaps someone else can refer us to a FAQ on what everything means - but the data output seems good but I'm not entirely sure what benefit it is to the listener.

It does work for P25 systems as well. I tried it on the DOJ system but it wasn't sync'ing up as well as the Mot Type II systems. (You do need a strong, clean signal for the audio function to work.)

-Nick


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PostPosted: Fri Oct 31, 2008 1:53 pm 
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Quote:
I haven't found a FAQ yet, so I'm not sure what everything all means.

paste what your looking at that you dont get and people will explain for you, or I will paste up a screen shot later this weekend

basically you can identify all the control and voice channels with the spacing, so your scanning along and find a system you can help learn or identify the system when you find the tell tale trunk control channel.

the data will also show radioID as you stated, show if its I call or Group Call show the Group Numbers so that you can log them all with out having to listen to them all, tell Icall to who... etc...


the program has three (IMO) major reasons to use it, 1) identify trunk systems 2) research id's on system 3) track users on the system and log data for analysis

also if you want some more fun with D-Tap or digital data... http://www.gsm-antennes.nl/PDW/

decode pagers, look for a old thread I started with all the frequency's for them.. its fun just remember its not totally legal so dont post your findings...


Quote:
It does work for P25 systems as well. I tried it on the DOJ system but it wasn't sync'ing up as well as the Mot Type II systems. (You do need a strong, clean signal for the audio function to work.)


if you dont have a TAP the digital compression of the audio of the uniden radios will greatly affect your ability to decode. I would highly recommend a D-Tap for P25 with this tool

its very easy to do to a 996 just post up i can print pix

_________________
If I had an antenna, I would; but I can only transmit on 160 meters.
_____
DE K7MHI


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PostPosted: Mon Nov 03, 2008 2:16 pm 
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Atomic Taco wrote:
kc7gr wrote:
The small circular transmitters...

Where? On the signposts?


I've seen them all over the place. The mounting location is highly dependent on where.

At the Bellevue TC, for example, they're attached to junction boxes mounted on the rafters above each bay. At the Kent Sounder station, I've seen them mounted on the signposts.

They require a data feed to be useful, and I've not seen any solar-powered ones as yet, so I suspect their presence is limited to the major transit hubs at this time.

_________________
Image
Bruce Lane, KC7GR
Owner, Blue Feather Technologies
Motorola programming and conversion service available. See http://www.bluefeathertech.com/rf.html
"Salvadore Dali's computer has surreal ports..."


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PostPosted: Mon Nov 03, 2008 5:56 pm 
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kc7gr wrote:
Atomic Taco wrote:
kc7gr wrote:
The small circular transmitters...

Where? On the signposts?


I've seen them all over the place. The mounting location is highly dependent on where.

At the Bellevue TC, for example, they're attached to junction boxes mounted on the rafters above each bay. At the Kent Sounder station, I've seen them mounted on the signposts.

They require a data feed to be useful, and I've not seen any solar-powered ones as yet, so I suspect their presence is limited to the major transit hubs at this time.

Those I knew of... never bothered to scan them though. Gotta play with trunker but I keep getting projects assigned.


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