I have recommendations, just like everybody else
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Cosmo, your antenna is good only for RF channels 2 through 6, so it would work only for the NBC station (and would work well - why not go ahead and put it up?). You would have to get a second antenna for the CBS station, like a Winegard YA-1713 or an AntennaCraft Y10-7-13 and combine the two with a HLSJ coupler. Results for the CBS station cannot be guaranteed for the reasons I cited before.
You should try to install your antennas as high as possible, doing your best to clear local obstructions. Tilting the front of the antenna up a few degress would help, too.