Mapping DMR Systems In The Tampa Bay Area

[CanesFan95]

We seem to have tons of DMR activity, especially on UHF, but it's too hard to figure out which frequency goes with what system and what the channel numbers are.

The Radio Reference Database lists a few Connect Plus systems, but it doesn't seem to have enough information to setup DSD+ for trunktracking (it doesn't tell you the over-the-air channel numbers for each frequency). Has anyone on here figured out the Busch Gardens system or other DMR systems in the area and would be willing to share their DSDPlus.frequencies file data?

 

[TampaTyron]

I have installed many dmr systems in the area and have figured out many more. The primary way I figure out systems is:
1-find dmr signal on xxxxxx frequency
2-identify possible system owner/physical location/other frequencies in system via FCC search
3-use dmrdecode to map the system, basically looking at the simple data dmrdecode gives on each channel
4-program system into xpr 6550, 7550 to test
*** many systems in Tampa use RAS to keep misfits out.... like Hillsborough County school buses, ,TBA's lcp, Telecom network's LCP, St Joe's lcp, etc.

I have a decent list of systems I have found so far, but would prefer not publicly sharing them. TT

 

[CanesFan95]

This will be very time consuming to do, and I've noticed that FCC geographic searches will sometimes show multiple ACTIVE results on the same frequency in the same county. I don't understand why the FCC licenses multiple repeaters on the same frequency in the same county when you know they'll only end up interfering with each other.

Most systems in the Tampa area are Capacity Plus with RAS unfortunately. But if the repeaters don't transmit their site number or LCN number, how can we piece together all the different systems?

 

[TampaTyron]

The primary reason the FCC has multiple repeaters in the same geographic area is there is a limited number of repeater pairs available in each band. When I find a dmr signal, I look up the license, then check to see what their emission mode is licensed for. A 7xxxxx is Mototrbo. I also look at all of the licensed station parameters such as antenna height, transmit power, etc I try to fully figure out the system, then listen/record the radio traffic to build a picture of what they use the radios for (a mall would not be talking about offloading ships, a port facility would not be talking about mall traffic/restroom cleaning) If there are multiple possible locations, then a road trip is in order to ID what is what. Keep in mind that there are systems that are not licensed, systems that have the wrong emission, power, height, etc on their license and systems implemented with auction frequencies that may not show up in an FCC search (454 band- I was involved with Auction-86 and implementing the Hills County School bus system). TT

 

[CanesFan95]

Now that's some real detective work. But I don't have an "XPR", so how do you figure out the LCNs on Capacity Plus systems?