Coax velocity factor
Velocity Factor = FACT: RF slows down when traveling within coaxial cable. The default of 0.66 is based on cheap and readily available RG58/U. Professional coax starts at 0.91 and higher, so check the specifications of your coaxial cable from the manufacturer before cutting your segments and remember to add some extra length for the cross connections! This specification is used in combination with known propagation of RF in space to compensate and get the correct element measurement for a given frequency.
This is an ideal "PVC pipe antenna", if space is limited, 1/4 wave segments will do fine, if the sky is the limit, 1/2 segments will be better, however, start and end the array with a 1/4 wavelength segment.
More than eight elements (including start and final 1/4 segment) have not indicated any significant signal gain. I therefore see no reason to extend the elements beyond this range in future.
TIP: Make sure there are no loose connections or short circuits between the elements before encasing and sealing the antenna in a PVC pipe.
Frequency calculations are based on radio waves traveling at the speed of light
299 792 458 meters per second.
Quarter wave segments
Using 1/2 wave segments:
A * 2: