138 MHZ p25 system heard around Pittsburgh PA

[nd5y]

5 VHF sites that close together doesn't make much sense if they are are at high level sites (200' to 500' or more) like a normal trunked system but like I said before it might be a field deployable system. The sites could all be on trailers with 50' masts and not far apart.

 

[Allen-KE8CCD]

Not really sure if it's phase 1 or 2.

I had 2 signal bars on 2 of the cc frequencies so I'm going to try my 14 element 70cm yagi and see what I get. Will keep everyone updated on what I find.

Allen

 

[redbeard]

I think I just had good condx last night as the 138.0375 and 139.1875 freqs I was watching are barely visible now. So this is def at some range from me.

 

[mtindor]

Jeff / Shawn,

My buddy Doc up in E Roch picked up all of the sites on the same day, after I sent him your findings. we concur that it was tropo -- no sign of a single one of them now, although he says that early in the AM he can see the strongest CC faintly on the waterfall. His best signal was with the beam pointed a littel south of Pittsburgh.

I'm betting it was tropo from the MD/VA/DC area -- perhaps one of the sites is at Mt Weather. At any rate, it's down in that direction somewhere. I'd recommend that people down in EWV, MD-DC-VA area be on the lookout for the actual sites in that vicinity.

Of course, since this thread is in the PA forum, that is going to limit it's "reach".

m

 

[BM82557]

Jeff / Shawn,

My buddy Doc up in E Roch picked up all of the sites on the same day, after I sent him your findings. we concur that it was tropo -- no sign of a single one of them now, although he says that early in the AM he can see the strongest CC faintly on the waterfall. His best signal was with the beam pointed a littel south of Pittsburgh.

I'm betting it was tropo from the MD/VA/DC area -- perhaps one of the sites is at Mt Weather. At any rate, it's down in that direction somewhere. I'd recommend that people down in EWV, MD-DC-VA area be on the lookout for the actual sites in that vicinity.

Of course, since this thread is in the PA forum, that is going to limit it's "reach".

m

I checked the other day when this first came up and had nothing at my location approx 70 miles west of the District. I just checked again and still nothing -

 

[mtindor]

I checked the other day when this first came up and had nothing at my location approx 70 miles west of the District. I just checked again and still nothing -


View attachment 76189

IT's just a hunch. Do keep in mind that with tropo, sites don't need to be strong or on a 500' tower at the top of a mountain. As such, a site pulled via extreme tropo could be a not-high-profile site and might not even be pulled in one or two counties away under normal circumstances.

Often when I would see tropo from my old Toronto location, it would be tropo to Eastern / SEWV -- I'd pull in the sites like they were 5 miles away from me, but I wouldn't pull in all of the sites between me and them. I love tropo. Hopefully somebody will figure out where the sites are. I think it's a good bet that they aren't more than one or two states away from WPA/EOH, for whatever that is worth. So I guess that leaves places like IN, KY, MI, Canadia lol, NY, NJ, MD, VA, DC. I'm sure somebody could narrow that down by just saying "hmm, where would there be a 4-5+ site federal P25 site setup that has gone undocumented so far". And the answer to that would probably be in a major metro area that also has significant federal presence.

Mike

 

[jeffm77]

Can you share the thread with your buddy? Every once in awhile, I can pick up the system on my sds100 with a anli high gain telescopic antenna, but not good enough to decode anything. I took my sds100 to work with me a few days ago, I work in west mifflin, using the same antenna, I get 4 to 5 S units on the display. But, didn't get any voice traffic.

 

[mtindor]

Can you share the thread with your buddy? Every once in awhile, I can pick up the system on my sds100 with a anli high gain telescopic antenna, but not good enough to decode anything. I took my sds100 to work with me a few days ago, I work in west mifflin, using the same antenna, I get 4 to 5 S units on the display. But, didn't get any voice traffic.

I already shared it with my buddy whoh was in East Rochester OHio and I reported what he picked up (pretty much the same stuff reported by you and Shawn). But, there is no sign of any of the sites now. So it had to have been a tropospheric ducting event going on that allowed you, Shawn, him and anyone else in our area to pick it up. It's not local . OR, if it is local, they just had all those sites online for testing and turned them off. But, like I said, after the tropo event was over, my buddy can still see a faint line on the waterfall for Site 2's control channel in the early morning. Early morning is usually when propagation is a little better. I'd bet that if you took the SDS100 to work on an average day, you probably wouldn't pick up anything at all from that system. Just my 2 ccents. That sure was a great find though. I'd think if it were in a "military" thread somewhere it would garner more attention from people in areas where such a system is likely to exist.

 

[Allen-KE8CCD]

I have to agree it's definitely not in NE Ohio or Western Pa, pointed by beam near Pittsburgh and Youngstown where the 2 bases are and no joy. signal disappears but once I turn the the antenna south around 110 112 degrees Azimuth the signal appears and had about 2 and 3 bars on the P25 system. my first guess was thinking it may be Greenbriar county WV where the radio telescopes are but could be wrong. looks like I'm going fox hunting to see if I can narrow it down.

Allen

IT's just a hunch. Do keep in mind that with tropo, sites don't need to be strong or on a 500' tower at the top of a mountain. As such, a site pulled via extreme tropo could be a not-high-profile site and might not even be pulled in one or two counties away under normal circumstances.

Often when I would see tropo from my old Toronto location, it would be tropo to Eastern / SEWV -- I'd pull in the sites like they were 5 miles away from me, but I wouldn't pull in all of the sites between me and them. I love tropo. Hopefully somebody will figure out where the sites are. I think it's a good bet that they aren't more than one or two states away from WPA/EOH, for whatever that is worth. So I guess that leaves places like IN, KY, MI, Canadia lol, NY, NJ, MD, VA, DC. I'm sure somebody could narrow that down by just saying "hmm, where would there be a 4-5+ site federal P25 site setup that has gone undocumented so far". And the answer to that would probably be in a major metro area that also has significant federal presence.

Mike

 

[redbeard]

Just for grins I thought I'd mention... I saw one of the Army's new Dash-8/RO-6A spy planes doing circles for hours around Greencastle, PA which is south of Letterkenny Depot and West of Raven Rock/Site R. North of the border from Hagerstown, MD.

I wonder if it's further south like Norfolk, VA.

 

[Allen-KE8CCD]

Just for grins I thought I'd mention... I saw one of the Army's new Dash-8/RO-6A spy planes doing circles for hours around Greencastle, PA which is south of Letterkenny Depot and West of Raven Rock/Site R. North of the border from Hagerstown, MD.

I wonder if it's further south like Norfolk, VA.

Very interesting indeed I almost forgot about the Raven Rock Mountain Complex facility. this is truly a project to determine where this is at. I did find some new frequencies with the same NAC code. so just for fun I added them in site 2 and 3 and got 4 and 5 bars of signal on my 536hp uniden. I did get a hit on a TG ID 15481 the frequencies I found were 138.5375 NAC 8AO 142.6375 NAC 8AO 142.725 NAC 8AO 142.350 NAC 8AO OF course it was 1 sided Communications but still interesting to listen to the guy in the clear.

 

[maus92]

The DoD LMR systems in the DC area are normally in the 380-400 range, but I'll see what I can find on the east side of DC - and the main wide area system is Harris.

 

[wa8pyr]

That might explain one or two sites -- not inconceivable that Shawn could pick up in that direction - he does pretty good over into that part of Ohio. But, The Ravenna Arsenal site already does have a pretty good presence on the MARCS system up there with quite a bit of activity on the MARCS statewide system. granted, their MARCS traffic is likely narrow in scope compared to what might be heard on their own dedicated site if one of the sites happens to be them.

The fact that Shawn can pick up four of the sites with varying degrees of success is pretty interesting. The question is what might it be that has five active sites within a 50 mi (or less) radius.

Ravenna Arsenal is also an Ohio National Guard facility now, so while it's possible they have a system on 138 MHz it's not particularly likely. There's not a huge amount of activity there, at least not enough to justify a system of their own. Even being part of a larger Ohio National Guard system isn't very likely; the state legislature probably wouldn't let them spend the money on such a system since MARCS is already there.

Just throwing this out, but wasn't the Navy a regular denizen of the 138 MHz band? I seem to recall Army and USAF generally more in the 160-170 range back before UHF became all the rage. If it's tropo from the MD/DC/VA area, maybe it's something for a group of Navy bases.

 

[redbeard]

Very interesting indeed I almost forgot about the Raven Rock Mountain Complex facility. this is truly a project to determine where this is at. I did find some new frequencies with the same NAC code. so just for fun I added them in site 2 and 3 and got 4 and 5 bars of signal on my 536hp uniden. I did get a hit on a TG ID 15481 the frequencies I found were 138.5375 NAC 8AO 142.6375 NAC 8AO 142.725 NAC 8AO 142.350 NAC 8AO OF course it was 1 sided Communications but still interesting to listen to the guy in the clear.

I have seen TG 15480 and 15484 so far with the most hits on 15481. Haven't copied any voice yet though. Did they have anything interesting to say that would give us a clue who it is? I've seen mostly clear traffic but some encrypted too.

I am sure the one morning I had good tropo to see all the sites I did, but site 2 seems to persist between full decode and just barely visible on the FFT. Just shooting from the hip I'm gonna say it's most likely Letterkenny/Site R/Camp David/Fort Detrick.

 

[Allen-KE8CCD]

I have seen TG 15480 and 15484 so far with the most hits on 15481. Haven't copied any voice yet though. Did they have anything interesting to say that would give us a clue who it is? I've seen mostly clear traffic but some encrypted too.

I am sure the one morning I had good tropo to see all the sites I did, but site 2 seems to persist between full decode and just barely visible on the FFT. Just shooting from the hip I'm gonna say it's most likely Letterkenny/Site R/Camp David/Fort Detrick.

Today was very quiet, couldn't find any of the cc hopefully I can pick them up again

 

[jeffm77]

I couldn't pick up anything at all today.

 

[redbeard]

Me either. I'll add Site C to the list too so I have 5 sites in my guess lol...

 

[redbeard]

Anyone still checking this out? I can still see a couple peaks on the spectrum, just not enough for a decode.

 

[TampaTyron]

Camp Dawson

 

[jeffm77]

Where's camp dawson?