I am pretty darn sure the MARATRAC and the similar M400 both have "signalling".
I just opened the RSS for each, and signalling is there.
You only get one per radio, not several like the Radius, MAXTRAC or GM300.
Pull up a file, F3 then F3, then F8 when you have one highlighted.
Then F10 to main, F4 to "change, etc".
Here is where it is different, then F2 to RADIO, F8 signalling options.
Use your up or down arrow key to scroll thru the choices. Then enter.
NOW, hit F8 change view, and you should see the values to change for the various signalling features.
After that, go to the MODE you want to enable signalling on.
I don't have a MARATRAC or M400 handy to dump it into, but I am pretty sure I used QC II in the past on these. Never tried MDC1200 to see how it displayed, but I would think it would be exactly like the MAXTRAC two character display.