Terry - from memory ( hope I recall it correctly)
The Switch module on the TX does not need power it connects to the main board ( more later)
The Multi-Switch-Prop 12+2 Decoder itself gets power from the lead that's attached to it that you plug into the RX.
However the additional switched/proportional outputs can draw quite a bit of power hence another battery is required.
I seem to think that it will depend on what version of the F14 you have as to where you plug the 12+2 multi switch pro mutli prop in on the transmitter board - on some there are 2 special sockets and some you use the actual channels - probably Ch7 or Ch8
Is your F14 new production or old kit? - might make sense to establish that before going further
I hope I am not confusing any of this with the FC16....
See this link -
http://www.rc-modellbau-schiffe.de/wbb2/index.php?thread/21908-multi-prop-decoder-modul-hilfe/I hope I am not confusing any of this with the FC16....
NB make sure your board looks like this one - same number of sockets - same printed legends - if not don't use any of the info below
This picture has 2 additional switch boards installed
Blue arrows (yellow cables) - are the outputs from the 12+2 board ( note 2 boards installed in this picture)
Red arrow - plug 12+2 board one into this socket
Black arrow - if you have installed 2 boards - plug the second extension switch board into the first as shown
Regards
C-3PO