No. Once voice alert is selected the TNC does the work with the CTCSS tone. Keep the volume up a shade on the side you run APRS on. When you hear a data burst, check your station list to see who may be on 146.52 (Or a local repeater), or you can just go to 52 and call a CQ.
I run it here, and although I've heard hundreds of packets, I've never made a contact..
Okay with voice alert activated, I still note that I have to use the squelch or the tnc won't transmit. So with this in mind, how close does someone need to be to break both the squelch and for the radio to capture tone? I think I am missing something here though I've gone over the information at aprs.org several times now. Don't think I ever did this with the 700 when I had it up and running.
Mark