Guys, think of this remote head as a PC with a virtual control program. It's exactly the same function and control codes and options available with both. These remote head-send-control-codes units have already been done for Icoms PCR1000 and several other black box receivers.
What could you do with a SD card on the PC when you can't download anything while in vitual control mode? Nothing. Can you have extra channels or extra options and features on the PC while in virtual control mode? Not very likely.
I belive the remote head also could be used with the BC246T as it has the exact same control codes, excluding software controllable volume and squelch ?
The BCT15/996 have an RS-232 port both at the rear and front. The rear is a 9pin d-sub connector and the front is a mini-USB connector but still RS-232.
The cable lenght will be about the same as with your PC connected to your scanner. If the head runs at 115k it will be pretty short distances, 3 meters, 10 feet but if the speed where reduced you could easily go up to 30 meters, 100 feet.
There are already programs available that mimics a serial RS-232 over the net, mostly used to access a remote fax modem, that you should be able to use with the remote head but then you also need to stream back the audio, probably easiest way would be to use an IP telephone like Skype.
Don't think of the remote head as a mysterious black box but instead as a very simple and slimmed down PC, and it will be much easier to understand what can be done and what is impossible to do.
Ubbe.