National Capitol Region Land Mobile Radio System

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n3bxv

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I'm hearing a control channel on 380.8375 on my old pro-26, 75 %decoding as 9600 using 380.84 in the Pro-96.

Any Clues? Meade's Land Mobile Radio system coming on line?
 

n3bxv

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Looks like
SY007
T0101
580A0

Pro96Com is producing the same results-

System ID:007
Tower 101
WACN 580A0
 

n3bxv

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Wow! Added to the RR Database already!

Mo, I'm pretty sure it's Meade or at least on this side of the post. I had to run to UPS in Laurel this evening to rescue a package, and the signal strength dropped off to almost nothing by the time I reached MD198 and I-95 and got steadily stronger as I returned to the Severn Area.
 

JamesO

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I wonder how eveyones automatic garage door openers are working in the area no that the control channel is active??!!!!

See reprint of article below.

JamesO

Fort Detrick Radio System Jams Remote Garage Doors
Updated: Sunday, Feb. 27, 2005 - 2:47 PM

FREDERICK, Md. - A new radio system at Fort Detrick will improve
communication with the Pentagon. The downside: some people may have to
open their garage doors the old-fashioned way.

The Land Mobile Radio system will allow Fort Detrick and 10 other Army
installations in the Washington region to communicate with the Pentagon
and civilian emergency personnel by hand-held radios.

In a suburban sacrifice to emergency preparedness, Frederick residents
could experience a rash of dead door openers in coming days, as the
Army's Fort Detrick begins using a new radio system linking local and
federal government emergency personnel.

The new system uses a frequency that has been owned by the military for
decades but used only by a couple of consumer devices, including garage
door openers.

Testing of the system has generated a dozen calls to Fort Detrick from
residents with problems, and when the system begins operating on 3,000
military properties across the country in coming months, hundreds more
complaints may follow.

"I think the Army ought to buy us a new opener or pay for a converter,"
Marty Kreps told The Washington Post.

"If the government was fair, they'd give us a tax deduction," Michael
Foster said.

Negative, the Army says.

"This frequency belongs to the military," said Michael J. Batt,
telecommunications engineer and frequency manager at Fort Detrick, who
is coordinating the radio system rollout. "I'd rather know Frederick
County has a radio system it can rely on in an emergency and have to
walk a few feet to open my garage."

In May, residents near Eglin Air Force Base in Florida had problems
with
their garage door openers while the base was testing its land mobile
system. In November, Fort Detrick finished work on a 150-foot radio
tower, which juts above a grove of satellite dishes about a mile from
the entrance to North Crossing. In mid-January, Detrick began testing
the radios.

That was about the same time Darlene Foster returned from the Safeway
to
find her garage door immobile. And the same week, Marty and George
Kreps
learned that to open their garage, Marty Kreps said, "you have to pull
up to the door like you're going to run into it."

Surfing the Internet, George Kreps learned that this was a known
problem
with two possible solutions: "Either you get a $60 kit" to change the
frequency "or you spend $150 on a whole new system.
 

JamesO

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I just saw the other earlier post with this article.

Sorry ML, it looks like you beat me to it.

JamesO
 

n3bxv

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Control channel moved

The control channel appears to have moved to 380.3875 sometime this evening and is Pro96com is now showing this CC and an additional channel as 380.8375

Does anyone know what "Unknown OP=38 Mfg:00" means? Its being displayed in the packet Dump view of Pro96com along with the Sysid, etc
 

n3bxv

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Severn, MD
Don't know what else to post, it's displaying as

B8 00 00 0C 0C 00 0C 0C 00 01 8F E1 Unknown Op=38 Mfg:00 in the packet dump window

and

B8 00 00 0C 0C 00 0C 0C 00 01 8F E1 Unknown Op=38 in the "Unknown Packets" window
 

mikey60

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Hmm. What does identifier table 0 show (it should be the standard 800Mhz one.

Do these come up a lot, or occasionally?

If they come a lot, I'd love to see the packet dump log file to see it in context with everything else that's transmitted. The system.ini, radio.txt and talkgroups.txt files might help with the meaning as well.

Mike
 

n3bxv

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Severn, MD
The Frequency Identifier Table shows

ID Base Spacing TX Offset A/C BW
0 380.00000 0.01250 -10.00000 C 0.01250

The Unknown Op = 38 packets scroll continuously in the Unkown packet window, time stamps show several a second...
 

ericcarlson

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There was a report on scan-dc of a P25 control channel on 380.275 that was reporting a manufacturer ID of "00" which is supposed to be a reserved code. This may be what you are seeing as well. Incidentally, the 380.275 freq was reported to be using 580A0 for the WACN, which is the same as the WACN on the new Fort Meade system in the database.

-Eric
 

mikey60

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n3bxv said:
The Frequency Identifier Table shows

ID Base Spacing TX Offset A/C BW
0 380.00000 0.01250 -10.00000 C 0.01250

The Unknown Op = 38 packets scroll continuously in the Unkown packet window, time stamps show several a second...

By chance, do you hear anything on 418.55? I think I'm decoding the offset incorrectly, it probably should be +10.00000. I think I saw something similar to this on another 400mhz system.

If you could send me a data dump of the control channel, and the data files you have, I can probably figure this one out (At least I can try). Please send to mbvv@wideopenwest.com.

Thanks,
Mike
 

n3bxv

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No, nothing on 418.55, this is most probably one of the new DOD systems in the 380 range......
Files should be on the way shortly...
 

mikey60

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It's obviously not a very busy system from what I can see on the dump file. We might have to wait a little longer to see what other traffic comes through on the control channel.


All I see in the dump file is the RFSS, network status, and the op=38. Not really even seeing the identifier updates in there at all, which I would expect to see on a regular basis (They are there, just not as often as I'm used to seeing them).

Mike
 

mikey60

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Ok, found my error on the offset, so that should be corrected on the next release of Pro96com.

I don't have any more information on opcode 38 at the moment. There are a couple ways to read it, but without more clues in the data stream, I can't confirm anything. There could be a couple radio IDs in there, or talkgroup IDs, or channel Ids (Not likely, you already checked 418.55 which channel 0-C0C would calculate out to).

Let me know when this system becomes more active. Maybe there will be more clues at that point. In the mean time, I won't have Pro96Com log these in the unknown window (They'll still be in the trace log, but not in the unknown).

Mike
 

TinEar

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Frequency 387.60 active with P25 encrypted voice transmissions. I wonder if this is part of this net. The signal is very strong and consistent with transmissions from Fort Meade to my location.

[Edit] 385.775 with same P25 encrypted voice activity.

[Edit2] Add 385.0625 to the list - same activity.

[Edit3] Freq 387.6 went to clear voice. Someone said, "We are testing the new system."

[Edit4] Control channel activity on 379.775 and more encrypted P25 voice on 380.175.
Something tells me we are about to lose our 400mHz Ft. Meade net. This net appears to be all encrypted.

[Edit 5] Two more encrypted voice freqs - 380.6875 and 381.1125. All of these transmissions seem to be from the same source. They have an odd short tone and data burst before the voice starts lasting just a half second or so.

[Edit6] I am also hearing a very weak control channel on 381.0875 which is NOT part of this net.
Add freq 381.875 to the list of encrypted voice freqs for our possible Ft. Meade net.

[Edit7] Add another freq with encrypted voice to the net - 387.3375

[Edit8] Add freq 380.4125 to the list. This one seems to have a problem. The voice doesn't seem to be encrypting correctly. Portions are in the clear. Let's mark this one as possibly part of this net. Same signal strength but the voice is two females talking. The other stuff is all male.

[Late edit] I've been trying to think where I've heard those same female voices because they sounded familiar. I'm now thinking it was possibly a patch of talkgroup 912 and/or 944 (the DPW or Johnson Controls) people on the Ft. Meade 400 mHz net. Just a possibility.

[Edit9] Control channel was pulled off the air at 1435 for about two minutes. It came back up one bar stronger than previously. A couple of minutes later it is going off and on again several times - off for just a few seconds at a time.

I have no idea how to find the base frequency or the offset so I can't enter this to recover talkgroups.

So far:
379.7750 Control Channel
380.1750 Encrypted Voice
380.4125 Encrypted Voice***(See Edit8 above)
380.6875 Encrypted Voice
381.1125 Encrypted Voice
381.8750 Encrypted Voice
385.0625 Encrypted Voice
385.7750 Encrypted Voice
387.3375 Encrypted Voice
387.6000 Encrypted Voice
 

ericcarlson

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With P25 systems, the frequency table information (base/offset/step) is transmitted over the control channel. The Pro96com utility will output this information. You should not need to program base/step/offset for P25 systems if the scanner recognizes the data sent on the control channel. However, I don't think there are currently any scanners that will let you program a trunk in the 380 MHz area.

If you have a Pro-96 you can use the Pro96com utility to log information on the system:
http://www.radioreference.com/modul...amp;sid=591&mode=&order=0&thold=0

-Eric
 
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