This will affect scanner users in various ways. Scanners of EDACS, LTR and conventional 800 MHz. systems will only need to change the
frequencies assigned to the System and scanners of P25 systems only need to change the Control Channels listed for the system. The very item
that made Motorola systems easy to monitor in the past makes it more difficult to deal with now.
Motorola handles frequency assignments differently than other systems. EDACS and LTR systems assign users to Channels in the system,
these channels are predefined as frequencies in the radios.
Motorola trunked systems assigns users to specific Frequencies, although by use of conversion "Tables". For this reason, Control Channel
Trunking works well most of the time on Motorola systems, the scanner understands the instructions from the trunked system's control channel
to look up the assignment code in the Table programmed into the scanner and then send the scanner to the proper frequency to look for that
conversation. Tables contain the formulas used to determine the frequency from the computer code on the control channel. Standard 800 MHz.
systems have used the same table for years and scanners were built around these Tables. Rebanding changes the Table so scanners will need to
be updated for these changes. Since some older scanners do not have the ability to be updated those older scanners will no longer work on
rebanded Motorola systems.
During the conversion process however there are multiple Tables in use, the original Motorola Tables used on non-rebanded systems and the
new Tables used by rebanded systems. Further complicating the matter is that the final version of the Table may not be etched in stone until the
Rebanding project is completed some years down the road.
For these reasons scanners of Rebanded Motorola trunked systems in the 800 Band will need to use the Custom Tables feature of the BCT15X
to monitor rebanded systems.
Programming a Rebanded System
When setting up the scanner for a Rebanded System in the 800 MHz. band you set the radio up for Motorola trunking then select "Custom" in
the Band Plan section of the Menu. You then set the Base Frequencies and other parameters as shown below:
Band Base Freq Base Freq Offset Polarity Spacing
Plan Lower Upper
1 851.0250 854.0000 440 + 25 kHz
2 851.0125 868.9875 0 + 25 kHz
Then go back and enter the frequencies used on the system.
Search & Scan Trunking Systems
When monitoring Trunked systems you can Scan them or Search them. SEARCHing a Trunked system allows you to hear all talkgroups used
on the system, regardless of whether you have them programmed in Scan Groups. If you have a talkgroup in a Group the Tag you programmed
will appear when the talkgroup is active, otherwise just the TGID will show. Use Search when you are unsure of all interesting TGID's.
When you set the radio to SCAN a trunked system it only checks the talkgroups you have programmed in Groups. Use Scan when you know
the specific Talkgroups you want to monitor.
I-Call
I-Call (stands for Individual Calling) allows users to communicate with only specific users, the traffic would not be shared with other users on
the system. Only the two radios involved in the call would hear it. The BCT15X allows you to monitor I-Calls by entering a I-Call number in a
Group, or monitor all I-Calls by entering an I-Call number of 0. This is different than older Unidens that had you turn I-Calls on and off in a
menu option.
I-Calls work on Motorola and EDACS trunked systems but not on LTR. Not all trunked systems use I-Call, it is up to the system's manager.
Hex or Dec or AFS: What's in a number (or letter)?
The BCT15X allows you to view Motorola Talkgroup ID's as either Decimal (using numerals 0 thru 9) or Hexadecimal (0-9 plus A, B, C, D, E
and F as numerals). Hex is the format in which many trunked systems are programmed in. This dates from the days when memory was
