Quote:
Originally Posted by slmoore
Just noticed that all of the channels I am getting are in the UHF range and the two I'm not getting are in the high VHF range (7 & 13).
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I think you hit the nail right on the head. Your two problem channels are in VHF while all your other channels are on UHF. This is a good indication that there may be something wrong with the VHF pickup of your antenna.
The short elements and "V" shaped reflectors at the front of your antenna are designed to pick up UHF frequencies. That part seems to be working fine.
The very long elements at the back of the antenna are the ones responsible for picking up VHF. Are there any "phasing lines" connected between those VHF elements? They are usually comprised of two stiff wires that criss-cross as they go between each of the antenna element pairs. This connects the elements on alternating sides of the boom. If you find these, make sure that are not electrically shorted to each other (there should be a gap each time they criss-cross).
On some antenna designs, the phasing lines also get connected forward to a place either directly connected to the antenna terminals (where the balun is usually connected) or somewhere close (allowing the signals to couple-in wirelessly).
If the phasing lines are shorted to each other or if they are connected to the wrong places, it might be causing your VHF elements to be "tuned" incorrectly and thus be ineffective at picking up VHF frequencies.