I'm new to scanning, but have purchased a Uniden BC75XLT. Here are the questions:
1. The manual uses the terms "Bank" and "Frequencies". Freescan describes Series and Groups. How do these terms relate?
How Systems and Groups are defined on a particular system varies a bit, but for a system like the Harris EDACS Trunked 800 MHz systems (formerly GE and MA/COM), systems are the individual sites used within an entire radio network including the conventional system. For example, East, West, North, South are 4 systems. Conventional would be a 5th but I don't scan those because CONV is generally radio-to-radio (point to point) with the exception of repeater conventional channels. For the trunked business end, each site contains a bank of frequencies. Some sites may have only 4 or 6 800 MHz freq's and a full site might have 16, 20, 24, depending on the engineering. The system is basically the infrastructure and are usually set up with a level of simulcasting to enhance signal propagation throughout a service area. Talkgroups or Groups are how each agency or "user" on the systems are allocated. Some systems separate by assigning a bank of groups to an agency, and use Logical ID Numbers (LID's) in a certain group for that agency. Or, there's a main talkgroup for dispatch and a number of tac groups for all Fire, EMS and LEO's within their own setup requirements. It's helpful to understand that the reason the scanner needs all that specific talkgroup identifiers is because of the trunking of these system. The only way to shoehorn hundreds of radios onto a relatively small set of frequencies is through trunking. So, when a firefighter out east keys up and the system reads that radio's LID (it already knows the radio is on because it's constantly pinging on the control channel), it broadcasts on lets say, channel 2 on the main site and then when the same person keys up again 10 seconds later, channel 2 might busy by another user and they're now on channel 8. The scanner can track the various frequencies by scanning them all sequentially, but the only way to make sure you're not scanning ALL users who are transmitting is by the specific talkgroup identifiers programmed into the scanner. And like on my radio shack PRO-163, by closing the "Bank" only those programmed talkgroups are supposed to be received.
Of course, as latter parts of your questions relate, how you program the Uniden with all the specifics about a talkgroup makes the thing work correctly. I'm only speaking of your question relating to how the terms are used in a typical setup.
Understanding how your system you want to scan is set up can make the process a lot easier. I knew my system intimately because I did my agencie's 800 MHz radio work for 11 years, but I didn't know jack about scanning with the 163 -- which is where these forums become invaluable....
Obviously, we're not transmitting but knowing what the nuts, bolts and how the system's gears turn is very necessary in my opinion.
As for your scanner, I don't have that kind of knowledge, but these very intelligent folks out here I am sure, do.
Thanks.
