You may be able to identify a trunking system by the control channel sound, a complete list of control channel sounds can be found
Once you have found a control channel you may be able to find out the other frequencies for the trunking system by checking
the ACA online database
normally the postcode/frequency search works best for this.
245XLT Tips & Tricks
If you own a 245xlt you may think you can only program the scanner with 10 trunking systems, in reality you can program heaps more
you can mix motorola 800MHz type 11 systems together in the same bank,(very handy if your area has a lot of small trunking systems) if you
dont want to hear one of the systems just lock out the control channel in addition to this you can also program conventional frequencies
You can also lock out all the trunking frequencies except for the control channel this is supposed to
make the scanner scan faster but remember the control channel may change & you may not hear a thing.
780XLT Tips & Tricks
If you own a 780xlt you can trunk 800MHz systems by just programming the
control channel a feature very handy if you dont know the voice frequencies.