Possibly slightly off topic.
Of the seven main Trunked Radio protocols around the world (Motorola, EDACS, LTR, MPT1327, SmartTrunkII, TETRA, and TetraPol), only three are currently supported by scanner manufacturers, and while there is some hope for MPT1327 support, I don't expect to see the last three supported 'anytime soon'.
As for sending Data and Voice over the Traffic Channel: I don't see any big problem with that for a scanner, as the Trunking System Controller (TSC) indicates whether the transmission is Voice or Data in the GTC (Goto Traffic Channel) message. Programs such as TrunkView, and I think UniTrunker*, handle it without any problems, only changing to the Traffic Channel for Voice messages, and ignoring the Data messages, as most scanner users are only interested in the Voice messages. Besides, a lot of Data messages are in proprietary formats, and cannot be decoded.
* haven't used UniTrunker on an MPT1327 system for quite some time, so my memory is a bit rusty.
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Comint