I am located in an area about 38 miles from the broadcast towers for CBS, ABC, PBS and NBC and am using an indoor Channel Master amplified Smartenna+ antenna mounted on a window. NBC, being a VHF station, unsurprisingly showed as a very weak signal on my station scan. Just for the sake of fooling around I put a 6 dB pad in the line at the Tablo Quad input connector and, voila, the signal strength indicator improved to the point I can watch NBC now. I’m guessing the scan’s signal strength indication measures signal to noise ratio, and if the signal is saturated it will increase this ratio. Just a hint for someone who might have the same configuration and problem. Attenuator pads are cheap - it might be worth picking up a 3 dB and a 6 dB pad from Amazon just to check it out.