CICA signal power -41.9 dBm = 7.1 dBmV
Max input 7778 = 34 dBmV
7.1 dBmV + 13 dBd ant gain = 20.1 dBmV; preamp OK
CICA -41.9 dBm + 13 dBd ant + 16 dB preamp = -12.9 dBm; tuner OK
You have a strong local FM transmitter 2.8 miles away that
might cause interference to TV reception, but it would affect VHF reception before UHF, the 7778 has an FM filter, and the two strongest FM signals are at the sides of your DB8e when aimed at WGRZ.
http://www.fmfool.com/modeling/tmp/f...9/Radar-FM.png
The fmfool FM database might not be up to date on Canadian FM transmitters.
You could always insert a filter between the antenna and the input of the preamp later.
https://www.antennasdirect.com/store...on_filter.html
The coax should be grounded with a grounding block connected to the house electrical system ground to make the rejection of interference more effective.
If the antenna is outside, the coax shield should be grounded with a grounding block that is connected to the house electrical system ground with 10 gauge copper wire for electrical safety and to reject interference. For further compliance with the electrical code (NEC in US), the mast should also be grounded in a similar manner to drain any buildup of static charge, but the system will not survive a direct strike.