Maryland FIRST 700mhz TRS

maus92

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Are you talking about the 8560015 RID? The low numbering xxx0015 suggests a fixed resource. Or maybe some sort of test configuration. Or possibly a foreign radio. I'd watch it for a while.
 

maus92

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Interesting. Unfortunately, I didn't transfer my Somerset data over to my workstation when I did some mobile testing on their new system several months ago. Curious.
 

maus92

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I wonder if they are patching from a MD TAC TG? Perhaps the Somerset system has ISSI with FiRST, but not sure why there is interoperability across the zones / regions - that's usually denied. Does SDRTrunk show patches?
 

LordDonkey

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SDRTrunk can detect patch calls as far as I know. This call showed up as a regular group call. I've attached the decoded messages and call events from SDRTrunk, there's also a copy of the call events that's been formatted as a spreadsheet.
 

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maus92

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Heard Anne Arundel County Fire Boat 19 talking directly on FiRST NRP Area 3 this evening. I don't think all land based units have this ability.
 

boatbod

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Heard Anne Arundel County Fire Boat 19 talking directly on FiRST NRP Area 3 this evening. I don't think all land based units have this ability.
Were they using one of the MARINE TAC channels? In that area I believe you'll find there is an almost automatic match to marine tac 4 for water rescues.
 

maus92

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This incident was on the Magothy River near Dobbin and Little Islands, Anne Arundel uses their Special Operation TG (Juliette) for water rescues, while NRP generally stays on their assigned channels. What I don't know is if FB19 was on FiRST directly, or on the still operating VHF DNR / NRP system - it sounded native. FB19 also has the ability to operate on CG channels (supposedly - I've never heard that) and the ITU VHF marine radio channels.
 
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maus92

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SDRTrunk can detect patch calls as far as I know. This call showed up as a regular group call. I've attached the decoded messages and call events from SDRTrunk, there's also a copy of the call events that's been formatted as a spreadsheet.
Do you use SDRTrunk 24/7? Can you post a zip file of system traffic over a 24 hour period? Or at least daytime hours?
 

maus92

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I've noticed some site additions to the FiRST database. The "Taylor's Island" site - which is actually the Smithville ASR - has an additional / new acch added. The added channel is not coordinated according to the latest CAPRAD database, nor does the FiRST system designate more that two channels as control channels per site. Whoever submitted should double check their data.

The upcoming Cherrytown Chicken ASR in Carroll County will likely be site 01-028.
 

WG3K

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I've noticed some site additions to the FiRST database. The "Taylor's Island" site - which is actually the Smithville ASR - has an additional / new acch added. The added channel is not coordinated according to the latest CAPRAD database, nor does the FiRST system designate more that two channels as control channels per site. Whoever submitted should double check their data.

The upcoming Cherrytown Chicken ASR in Carroll County will likely be site 01-028.

I got that frequency from the peer connection to another site (don't remember which one at the moment). Not sure why they added it as an additional primary control channel. I'll try to verify the control channel today.
 

LordDonkey

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I try to keep it running 24/7. Attached is the zip file. It covers call events from 3/27 at 10:18 to Today at 15:26. I've merged them both into a spreadsheet for easy sorting. I've also included both log files that's in the spreadsheet.
 

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maus92

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I try to keep it running 24/7. Attached is the zip file. It covers call events from 3/27 at 10:18 to Today at 15:26. I've merged them both into a spreadsheet for easy sorting. I've also included both log files that's in the spreadsheet.
Thanks!
 

maus92

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OK
I try to keep it running 24/7. Attached is the zip file. It covers call events from 3/27 at 10:18 to Today at 15:26. I've merged them both into a spreadsheet for easy sorting. I've also included both log files that's in the spreadsheet.
OK, what I was trying to do is verify the remaining site voice channels for the Garrett Simulcast, but the math is giving me results I don't believe for 2 of the channels. SDRTrunk is reporting channel numbers 3-1024 and 3-962 as voice channels, but the math converts them to 768.01875 and 768.40625, which are in the guard band. They *should be* 769.40625 and 770.43125 according to frequency coordinator data, with channel numbers 1184 and 1348. The channel numbers that don't convert properly are TDMA channels; the FDMA channel numbers convert properly. I'm trying to figure out if the program is reporting bad channel numbers for TDMA channels, or if I'm missing a step somewhere - or the frequencies are correct and the coordinator data is wrong. Is there anyone in Garrett that check the actual frequencies that are in use?
 

maus92

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The NCR MD TACs were in use yesterday. Sounded like they were being used to monitor parks.
 

LordDonkey

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The system does use 769.40625 and 770.43125 when 774.03125 and 774.80625 are busy. I can try and find an event log when the lower frequencies are in use, if you'd like. I don't hear voice on 769.40625 or 770.43125 since it's out of the range of my SDR.

Side note: GCSO started having radio issues just after 2:52 PM. Deputies are calling dispatch on Sheriff Tac 1, but nobody from Garrett Central is responding. They also were trying GCSO Main (12621) and weren't getting a response. (Edit: Dispatch is now talking back again on Tac 1, still nothing out of Fire/EMS Main or GCSO Main. 3:31PM)
 
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maus92

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The system does use 769.40625 and 770.43125 when 774.03125 and 774.80625 are busy. I can try and find an event log when the lower frequencies are in use, if you'd like. I don't hear voice on 769.40625 or 770.43125 since it's out of the range of my SDR.

Side note: GCSO started having radio issues just after 2:52 PM. Deputies are calling dispatch on Sheriff Tac 1, but nobody from Garrett Central is responding. They also were trying GCSO Main (12621) and weren't getting a response.
That would be great.

Hmmm, not good that nobody was answering - I'm assuming you heard them calling on the TGs. Is the old system patched into the FiRST TGs, or are they using the systems separately - or have they retired the old system entirely?
 

LordDonkey

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Seems like dispatch is talking back now. But yes, they were calling over the talkgroups. The old system is patched into FiRST. As far as I know some of the mobiles are still VHF, although I've noticed that some are talking with 2 different RIDs now. They have an RID in the 24210xx range and one in the 24211xx range, except the one with a RID in the range of 24214xx and 24215xx.

A few days ago, most of the old radios were patched into GCSO Main with the dispatch RID (2135506) and then with a delay, maybe 350ms or so later, the same thing would transmit over Tac 1 with the other dispatch RID 2127479. The same happened in opposite when a digital radio would transmit over Tac 1, it would transmit over GCSO Main with the RID of 2135506.
 
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