Trunked System

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sclark1955

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I purchased a Uniden BCT15X scanner and ARC XT Pro software to program the scanner. I am having trouble with the trunked systems. I get them loaded just fine but when there is broadcast all i hear is noise not talk. I found this in the RadioReference.com and it seems to fit the problem.

You may be listening to the data on the Control channel as audio. The system must be programmed as a trunked system. Your scanner must support trunked system monitoring. See this category page to see the scanners that can monitor trunked systems.

Can someone help?
 

ka3jjz

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Let's start with what system you are trying to hear. If the voice entry in the db says 'APCO-25 Common Air Interface Exclusive', the 15X can't handle it. You need a digital trunktracker for that - either the 396XT, 996XT, Home Patrol or the 2 new ones coming out next month.

Go up top left under the site title, float your mouse over Database and select Frequency Database. Use the various pulldowns and the map to get to the URL of the system. C'mon back with that

Mike
 

br0adband

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If you get a paid subscription to this website you can get access to the entire Radio Reference database which can be downloaded into the ARC XT Pro software and then uploaded into the scanner - that would take care of pretty much everything necessary, for the most part (and for most casual listeners).

It sounds to me (no pun intended given your listening issues) like maybe that scanner is a bit more complicated than you may realize. Because of it being so complex, and the owner's manual being somewhat easier to not understand, someone out there wrote a nice "easier to read" guide to using the BCT-15X and you can find that guide here:

Easier to Read BCT15-X Scanner Manual

As for the control channel data, when using a modern scanner that supports control channel decoding, all you really end up having to tell the scanner is two things:

1) The control channel (aka CC in this usage, and I don't mean CC for CloseCall, the frequency detecting mode of operation) frequency or frequencies (which you get from the info here in the database or some other source for that info)

2) Enable the setting or option in the scanner to do what's typically referred to as "CC only" or whatever the specific option is which tells the scanner "Hey, you know that control channel frequency or frequencies I just programmed into you? Well just listen to those and decode what you need to be able to switch around to all those voice frequencies as required."

The control channel data stream carries all the necessary info for the scanner to "know" when to switch to the voice frequencies so you can actually monitor the comms. If you're only hearing the control channel itself, more than likely you've got a system programmed with at least the CC and that's all it's able to scan until you tell the scanner to decode it as necessary which is the "CC Only" option iirc.

If you're so inclined, there's a wiki page about Control Channel Only operation as well:

http://wiki.radioreference.com/index.php/Control_Channel_Only

When you end up having some incredibly complex trunked systems, it's nice to know this feature exists nowadays and instead of having to punch in hundreds if not thousands of frequencies manually, you just input the CC frequency or frequencies and the scanner does the rest - that is if "CC Only" decoding is enabled.
 
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ka3jjz

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I found the frequency database. What do you mean by pull downs and map to get url

If you went to the frequency database, you'll see a map of the US and a number of pulldowns below it. Find your state and click on it in the map, and you'll be taken there.

At the top of that page you'll see a tab for Trunked Systems

Mike
 

hiegtx

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I found the frequency database. What do you mean by pull downs and map to get url
Based on the location you show, you're in Highland County.

It appears, from the database page linked above, that most of the law enforcement agencies, including the Sheriff's Dept., are on this system:
Ohio MARCS - Multi-Agency Radio Communications Trunking System, Statewide, Ohio - Scanner Frequencies

That is a Motorola Type II system, but if you look at it's details, it says:
System Voice:APCO-25 Common Air Interface Exclusive
In other words, all communications are in digital mode, which your BCT15X cannot decode. You'd need to upgrade to a digital scanner for them.

If you are trying to program a different trunked system, then, Mike (ka3jjz) noted, provide a link to it's page or the name/location.
 
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