Based on what I saw on your TVFool.com report, your observations about the 4 stations that you are now getting seems accurate: they are the 4 strongest signals in your location, but that means that you aren't seeing the bulk of the stations Seattle, which includes most of your major networks. If we are going to succeed in seing the other Sea-Tac stations, we are going to need a deep-fringe UHF antenna aimed at the cluster of transmitters in Seattle, 45-50 miles from your house.
The stations that you are calling "Low-channels" , channels 4 and 5 have since moved off to UHF, so you really don't need an antenna like a
Winegard HD8200U, since the most of the size of that antenna is meant to see the old low-band channels 2-6. I am going to recommed a two-antenna system to you that will out-perform any existant combination antenna, but is a more managable size and cost.
I usggest using a
Winegard YA-1713 VHF high-band yagi and an AntennasDirect XG-91 UHF antenna mounted on your roof. Mount the Winegard and the AntennasDirect on the same mast, with the Winegard 4' LOWER than the AntennasDirect XG91 on the mast. The XG-91, which is fairly light, shoud be mounted at the estreme top of the mast. Aim the XG-91 at about 15 degrees by your compass, and aim the Winegard in roughly the same direction.
Connect the two antennas using RG-6u coaxial cable, and bring the leads to one point on the mast where you will use a pico-Mcom UVSJ antenna joiner: connect the VHF antenna to the correct input, and the UHF antenna in the same manner. Run the output of the joiner into a Winegard HDP-269 preamplifier, then run the output of the preamp's coax cable into the house. Locate a place in the house that is central to all three TV sets that also has AC power available: an attic, basement or utility closet is ideal, then connect the preamplifier's power supply to the incoming coaxial cable, and connect the output of the preamp power supply into high-quality 1 ghz or better 3 or 4 way splitter, then run the output of the splitter to each of the TV sets. Please follow the instructions in the installation manual that i will link to you below, especially regarding grounding and safety instructions.
Once the antenna is connected up , and the power supply is plugged in to the AC, go to eacn TV tuner and have the tuner scan for digital stations. In some cases, weak TV sations may be bypassed by the scan, but can later be entered manually into the remote-control's keypad. Once done, you should have all of your Sea-Tac stations restored to you.
http://www.winegard.comhttp://www.antennasdirect.comhttp://www.picomacom.comhttp://www.channelmasterintl.com/docume ... lation.pdf