Hey Matt_B!!!! Try going Carrier-Current if you are APT bound. That's how I started out, with a Panaxis AM-100 TX, (100mW TX.), to a 100uH coil and Neutral Injected that. How did it work? I was GND Floor of an APT complex and it covered into several buildings. So, not bad. Today, I have some better gear and use either the LPB T-8, or the Radio Systems CP-15, AM C-C Couplers. BTW, if you can, best to use an Independent GND rod to the Coupler. Also, look for any books about the subject from Ernest Wilson and James R.Cunningham to download and apply. A lot of stuff you can build yourself, and you might have to, since anytime LPB and RS stuff come up on ebay, they get bought out almost immediately. So, someone wants that stuff, badly.