**Here is how to figure out your true 1/2-wave: **

492 x (Velocity Factor) / Frequency (MHz)

For example, I want to figure out the true half wave coax length for RG-59/U (foam) on my home channel (ch. 33 - 27.335):

492 x .79 / 27.335 = 14.22 feet

Now add 14.22 to itself to determine your 1/2 wave multiples. Remember to use every other number. See the example below:

14.22 feet 1/2-wave multiple

28.44 feet 1-wave multiple

42.66 feet 1/2-wave multiple

56.88 feet 1-wave multiple

71.10 feet 1/2-wave multiple

85.32 feet 1-wave multiple

and so on . . . .

**Use only the lengths that fall on the 1/2-wave multiples**

and you will be all set.