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Both antenna are connected to a splitter via lines that are equal in length. The combined signal feeds the CM-7777.
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Not a good idea, because when the same signals arrive at the combining point, they will interfere with each other if they are not in phase. But it gets even worse: if you have two different transmitters on the same channel because of co-channel assignment, they will interfere with each because they are bypassing the F to B ratio of your two antennas aimed in different directions.
Equal length lines are only required when you have two identical antennas aimed in the same direction for more gain. It's irrelevant in your setup.
Tim is correct. The curvature of the earth begins to block signals at about 70 miles, and Tropo signals will never be reliable.
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The following channels we would like to receive all the time are WJXT, 4.1; WJXX, 25.1; WFDX, 30.1. These and others come in fairly good at night.
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WJXT, real channel 42, virtual channel 4.1, NM -14.1 dB, 174 degrees true; co-channel interference from WJBF, real channel 42, virtual channel 6.1, NM -14.7 dB, 357 degrees true
WJXX, real channel 10, virtual channel 25.1, NM -14.9, 174 degrees true; co-channel interference from WALB, real channel 10, virtual channel 10.1, NM -20.5 dB, 259 degrees true
WFDX, real channel ? I don't see that. If you mean WFOX, it has the same problem with WPGA.
A signal must have a Noise Margin of at least 0 dB to be received. You can add the antenna gain to the NM figure on the TVFOOL report, and you can also add the gain of your preamp, but must subtract the NF of the preamp because it adds its own noise that reduces the SNR of the weak signal.
Interpreting Noise Margin in the TV Fool Report
http://www.aa6g.org/DTV/Reception/tvfool_nm.html
The NM of your strongest signal WTGS is 56.5 dB. If you add the preamp gain of 30 dB, that brings you up to 86.5 dB before adding DA gain and subtracting distribution losses; clearly overload territory for the preamp and tuner.
Two or more of your strongest signals can create spurious signals from Intermodulation Distortion (IMD) that can wipe out your weakest signals.
You have some strong local FM signals that might interfere with TV reception. See attachment 2. The FM trap in the 7777 probably will take care of them if they aren't too strong. FMFOOL reports don't link like TVFOOL reports. You can run your own FMFOOL report using your exact address here:
http://www.fmfool.com/