Hi Jerry and Group;
If the tuner runs off twelve volts you can hook it to your power supply with 
no problem.  You will have to change bands manually.
There is a connector on the back of the 751a for a tuner interphase. 
Whether there is an interphase that would let the tuner and 751a work 
together, however, I don't know.  You don't have to have the interphase 
Jerry to use the tuner.  It just will auto band change and is a cool extra. 
At this point you probably want to get your antenna issues resolved first.
Icom changed their tuner plug when they went from the 751a to the 835.  I 
was using an at500 and there was an adaptor.
Richard