I'm not sure of the exact configuration of your mixer, but I'll take a stab at it for you.
Most of the TASCAM integrated units work as follows.
Select the tracks you wish to bounce and the track you wish to bounce to and set the channel input switches to "TAPE".
Turn the pan pots to R or L depending on which buss the track you are bouncing to is on. Enable record mode on the track you are bouncing to and select which buss it is assigned to.
Balance your reletive levels and overall mix to get the sound and S/N ratio correct. Hit record and let the tape roll.
When bouncing, you may want to add just a bit of high-end and roll off a little low-end. You may have to experiment with this to get it right unless you know from experience what your bounced tracks sound like after the bounce. You will loose some high frequency doing a bounce and the lows sometimes get a bit muddy depending on what you are bouncing.
Listen to your bounced track and shut of the original tracks to hear the difference.
If this procedure is not correct, visit the
www.TASCAM.com message board.