New P25 System, LA City

[LAflyer]

OK, ran unitrunker on each system for 2 hours each.

008 is the much busier of the two. Bulk of activity on 001 was the 65xxx TGs.

Anyhow below are the logs of TGs which were noted on each site:

001:
102 - picked it up once. Error??
20163
20165
20166
20167
20168
20170
20175
20179
20180
20588
65337
65343

The 65xxx TGs each had excess of 140 hits each, while the 20xxx were in the single digits or low double digits during the 2-hour time frame.


008:
20166
20168
20193
20194
20195
20577
20579
20580
20584
20585 --- busiest TG of the group (almost 200 hits)
20588
20592
20609
20615
20630
20631
20633
20634
65337
65339

The TG activity was higher here with hit count between 35-200 over the 2-hours for each TG. 65337 was fairly busy also here, but did not reach the 140 count it did in 001, but this of course could be simply due timing and less activity when I was running the 008 analysis.

You'll note some TGs (20166, 20168, 20588, 65377) were duplicated on both systems, but most TGs seemed unique to each site.


Getting back to the sites themselves, I am not 100% convinced they are in the same places.
001 reception was mostly in 82-86% range using an outdoor antenna while 008 comes in today in the low-mid 90's from my location. So some things such as location, or power is different between them in my opinion.

I'd like to see how others pick up these sits around the LA basin.

[bcorbin]

Thanks LAFlyer!

That's the sort of asymmetry I would expect for a sys2/sys3-like split, *except*, if the AFS->P25 mapping holds, it doesn't appear to be split by agency (which likely kills the sys2/sys3 idea). Maybe the site assignments are regional? That might give us a hint where the sites are (or where the antennas are pointed 8*) ).

Might also be useful to look at where the Sys2 and Sys3 sites (EDACS) were/are located - chances are, if the valley coverage was achieved by co-locating the repeaters, these are co-located... ?

I need to do a little more research on P25 trunking and figure out what the 65### patches are doing. As soon as I finish up my day-job tasks 8*)

[LAflyer]

The original EDACS sites are Mt. Lee, Rolling Hills, Oat Mountain, and Mt. Washington(by Dodger stadium)

Baldwin Hills and Mt. Lukens are new "fill-in" sites authorized in 2012 in anticipation of P25.


Considering the signals are reported both strong up in SCV, while so-so in the basin I guess we are hearing either Oat or Lukens, or maybe both due to the signal strength variance I noted between 001 and 008.

[Chauffeur6]

Looking at the DB, are those both Site 001 with a different RFSS, or should it be RFSS 1 Site 001 and RFSS 1 Site 008? It's usually the latter, but obviously I'm not exactly in a position to verify that.

[MtnBiker2005]

Site 001 reporting this from Pro96com

RFSS Status Broadcast - SysID: 0D5 Status: Connected Zone: 1 Site: 1

 Mfg A4(M/A-COM/Harris)

(Comes in weak in San Diego County)

[LAflyer]

MtnBiker - are you not able to hear 008 at all? Control channel is back to 866.3625 this morning.

In my experience, Mount Lukens can often be copied pretty far South and well into OC, while Oat does not.

Might help place a location on 001 vs 008.

[MtnBiker2005]

Someone should see if the "FCC license" will show up on those two sites on the Pro96Com software.
Someone with better signal need to run the software for under 1 hour. Some P25 sites do and don't send it out. Won't know till someone tries looking for it.

At this time I haven't logged/heard Site 8 yet from my monitoring spot in San Diego County.

[LAflyer]

Never used Pro96Com, so tried it.

According to the Site Information it produces the Callsign box is blank. Also for sites it registers 101 and 808 instead of 001 and 008.

Additionally I note it produces a breakdown of patches.
20164 > 65353
20165 > 65370
20166 > 65369
20167 > 65353
20168 > 65369
20179 > 65343
20180 > 65370
20183 > 65343


For reference site 001 control is 866.3875 this morning.

[MtnBiker2005]

umm... You let the Pro96Com run for about 30 minutes ? (Maybe these two sites not sending it yet)
Need to wait for the CWID to be sent out from the site. Till it shows up in the blank callsign box.
It works great for sites like in State of Colorado and Riverside County new P25 system.


You can read more about the site in the "Dump-101.txt" or Dump-108.txt" Pro96Com logs.

[Chauffeur6]

Originally Posted by LAflyer

Also for sites it registers 101 and 808 instead of 001 and 008.

It's displaying 101(T0101) and 808(T0808) for the Site ID's? If so, then that reads as RFSS 1, Site 1 and RFSS 8, Site 8.

You'll need to update the Site # for Site 8 in the DB, it's currently listed as RFSS 8, Site 1.

[Jay911]

Originally Posted by LAflyer

Also for sites it registers 101 and 808 instead of 001 and 008.

That would be because P25 systems actually have a two-part "site number", to put it simply. The first part is the "RF Sub System" or RFSS and can be a number from 1 to 254. The second part is the "Site ID" and can also be a number from 1 to 254. They don't have to be the same number, and they don't have to be unique to one another. It all depends on the system builder. Some agencies seem to like to build with RFSS and SID the same, and some build with RFSS of 1 and SIDs in numerical order. Larger systems may build with RFSSs of 1, 2, 3, etc., and SIDs in numerical order, re-used from one RFSS to another; the big US DoD system 14C shows an example of that. One system I was monitoring last summer has multiple RFSSs with all of them having SID 1 in them, which is kind of backwards to the norm.

In your case the two sites are RFSS 1, site 1 (generally displayed as 001-001) and RFSS 8, site 8 (008-008).

Many programs and scanners display it differently. As you've found, PRO96COM displays it as 0101 and 0808; Uniden radios display it as 101/808 if I recall correctly (I should check on my local system which has RFSSs/sites in the two and three-digits), and GRE radios display (in Analyze mode) as "R001 S001" or "R008 S008" etc.

However it is displayed, there will ALWAYS be two parts to the "site number". It's important to put them in the DB correctly for those people who download the DB into Unitrunker or PRO96COM, etc.

Originally Posted by MtnBiker2005

umm... You let the Pro96Com run for about 30 minutes ? (Maybe these two sites not sending it yet)
Need to wait for the CWID to be sent out from the site. Till it shows up in the blank callsign box.
It works great for sites like in State of Colorado and Riverside County new P25 system.

Some systems never populate the "Call Sign" field in PRO96COM. However, if they do, on your "System Activity" screen, you may see a frequency with "Usage" set to "i" (either alone or with other usage codes). That means that frequency is identified by the system as being used to send morse code ID or other FCC/IC/etc required identifiers.

[Chauffeur6]

Originally Posted by Jay911

In your case the two sites are RFSS 1, site 1 (generally displayed as 001-001) and RFSS 8, site 8 (008-008).

Is there an echo in here?

[LAflyer]

I let Pro96com run again for almost an hour on 101. No CWID was noted in the logs.

I'll fix the RFSS later tonight from home.

[Chauffeur6]

Originally Posted by LAflyer

I'll fix the RFSS later tonight from home.

Both Site RFSS entries are already correct, you just need to change the Site Number for "Site 8" to 8 instead of 1.

[bcorbin]

Originally Posted by LAflyer

The original EDACS sites are Mt. Lee, Rolling Hills, Oat Mountain, and Mt. Washington(by Dodger stadium)

Baldwin Hills and Mt. Lukens are new "fill-in" sites authorized in 2012 in anticipation of P25.


Considering the signals are reported both strong up in SCV, while so-so in the basin I guess we are hearing either Oat or Lukens, or maybe both due to the signal strength variance I noted between 001 and 008.

I'm (almost) back 8*)

I would be *amazed* if I was hearing Lukens from my location in the SCV as well as these two sites are coming in. I'm line-of-site to Magic and Los Pinetos, darn-near to Frazier and Oat, and on a good day I can hear Hauser, but I'm pretty-well shielded from LA City. If I drop down into the valley a little I can sometimes hear Mt Harvard, but no where near sufficient to recover a digital signal.

If that's a complete list of sites, I'm thinking they're both on Oat, with different footprints... (008 set up to cover most of north city and 001 as a filler?)

[bcorbin]

Originally Posted by LAflyer

Never used Pro96Com, so tried it.

According to the Site Information it produces the Callsign box is blank. Also for sites it registers 101 and 808 instead of 001 and 008.

Additionally I note it produces a breakdown of patches.
20164 > 65353
20165 > 65370
20166 > 65369
20167 > 65353
20168 > 65369
20179 > 65343
20180 > 65370
20183 > 65343


For reference site 001 control is 866.3875 this morning.

Note the dynamic assignment (20165, 20180 -> 65370). I think it'll be a lot easier to resolve what is going on if we ignore the patch TG's for now 8*) Once I get my computers freed-up from their current task, I want to put one on 001 and the other on 008 and see if there is anything of interest happening simultaneously (vis the patches?) on the two systems...

[Chauffeur6]

Originally Posted by bcorbin

I'm (almost) back 8*)

I would be *amazed* if I was hearing Lukens from my location in the SCV as well as these two sites are coming in. I'm line-of-site to Magic and Los Pinetos, darn-near to Frazier and Oat, and on a good day I can hear Hauser, but I'm pretty-well shielded from LA City. If I drop down into the valley a little I can sometimes hear Mt Harvard, but no where near sufficient to recover a digital signal.

If that's a complete list of sites, I'm thinking they're both on Oat, with different footprints... (008 set up to cover most of north city and 001 as a filler?)

For what it's worth, the antenna on Lukens is at 5,000' elevation, and the antenna they show on the license is directional and fairly high gain at 13.5 dBi, licensed at 100w (1,000w ERP). It's pointing 285° West-Northwest, which has the signal aimed almost directly at Oat and just to the south of the SCV. At just under 20 miles between Lukens and Santa Clarita, it's really not too far fetched that you'd be hearing that site pretty decently.

The directional antenna pointing West-Northwest might also explain MtnBiker not hearing Site 8, if it is Lukens. Since Lukens is a newer site, the WQPI386 for that site being a Special Temporary granted earlier in the year, Site 8 would make sense for that, while the existing site at Oat might be Site 1.

Brent, did you say which site you're getting clearer? And have you tried turning attenuation on to see if one of the signals really drops out?

[bcorbin]

Originally Posted by Chauffeur6

For what it's worth, the antenna on Lukens is at 5,000' elevation, and the antenna they show on the license is directional and fairly high gain at 13.5 dBi, licensed at 100w (1,000w ERP). It's pointing 285° West-Northwest, which has the signal aimed almost directly at Oat and just to the south of the SCV. At just under 20 miles between Lukens and Santa Clarita, it's really not too far fetched that you'd be hearing that site pretty decently.

The directional antenna pointing West-Northwest might also explain MtnBiker not hearing Site 8, if it is Lukens. Since Lukens is a newer site, the WQPI386 for that site being a Special Temporary granted earlier in the year, Site 8 would make sense for that, while the existing site at Oat might be Site 1.

Brent, did you say which site you're getting clearer? And have you tried turning attenuation on to see if one of the signals really drops out?

Well, could be, but... draw a line from line from Lukens to my place, and it will have to cross Magic (very near the peak) along the way. There's a lot of natural attenuation to begin with and I'm off the side of the lobe. I'm not going to say it's impossible, but topologically, unless I'm missing something, it doesn't seem super obvious. I can't think of anything else I can hear from Lukens. It would almost have to be knife-edge, in which case I would expect to see a lot of short-period refractive path variation.

Having said that.... 8*)

I didn't pay as much attention to this as I should have before I got swallowed-up by other things, but I think I noted some significant strength variation on one of the systems about the time it did a CC swap - may or may not mean anything, but I'll definitely follow up once the dust settles on this other project.

If I weigh the investment (in frequencies and talk-groups) in Site 8 vs Site 1, proportionally, it's about what you'd expect if you were going to cover north-metro on 8 and fill-in west-valley on 1. The geographic representation on 8 seems to be consistent (in that most of the activity on 8 seems to be from areas that would have a better shot at Lukens than Oat)...

You may be on to something 8*)

EDIT: But why would the antenna point from Lukens towards Oat??? That's really quite the wrong direction if you want to squirt signal back towards the city.... 8*P

[Chauffeur6]

Here's a visual representation of the direction the antenna is aimed. The centerline is at 285° and the outer lines are at 240° and 330°, as the antenna has a 90° beamwidth.

Of course this is vastly oversimplified, and without knowing the exact model antenna being used, there's no way to know what the radiation pattern actually looks like. There is no detailed antenna info for the Oat site, so I suspect it's probably an omni up there.

[LAflyer]

Thanks for the added input guys.

Atleast from my location in the LA basin (mid-city/Beverly Hills area), 008 comes in slightly better so it make more sense if that was indeed Lukens as in general I can hear Lukens decently (I monitor some business LTRs up there), while Oat tends to be fainter being hidden behind a few hills along the way.

I guess some of this will be wait and see as the system build out continues. From my location the best sites would be Mt. Lee and Baldwin Hills which directly overlook the central city area.