[John Candle]

Stacking 2 identical tv antennas vertical or horizontal is easy. Vertical stacking is often done around airports , the large bodies of the planes make great reflectors. and in the case of diffraction , vertical stacking is done when a hill or mountain or something else is in line with the receiving antenna and the transmitter. With vertical stacking one antenna is fixed in place and the other antenna is moved up and down to reduce the vertical multipath. Horizontal stacking is done when signals are reflecting off of buildings , trees , mountains/hills etc.. For horizontal stacking the antennas are side by side , one antenna is in a fixed position and the other antenna is moved closer and further away to find the sweet spot , the desired result of multipath reduction or elimination. For horizontal stacking the mounting is often made of steel pipe like water line pipe or even gas line pipe. The pipes are very strong and do not bend. There is way to much information on the net about tv antenna stacking.