The display will show the voice channel and the control channel when stopped on a trunk system talk group.
Holebilly, your display will alternate between the two, saying something like 'CC02 866.4250' when it shows the control channel. If you know the order of your control channels, then you can basically tell which site it's coming from
For example, if CC's 01&02 are from site A, 03&04 from site B, etc, and it says 'CC02', then it's from site A. 'CC03' is from site B.
I used Win500 to switch on 'Show trunked chan w/VC', then wrote down the order of the System Frequencies from the TSYS Objects tab along with the corresponding site from the RR Database ... and it seems to work for me on MARCS.