I will be joining my HD Satellite Disk (Dish Network) with my DTV OTA HD Antenna at the main input for my house. I have good HDTV signals so I'm looking for a good Diplexer as too not to lose too much signal for the run. The run is about 100 feet and I'm running RG6 cable from the Antenna to junction box. The cable must run through the junction box as that is where the ground is located. Then from the junction box to the TV is about 60 feet.

Any recommendations on what to look for in a Diplexer?