script calculates the values concerning VHF UHF and SHF SperrTopf
Antennas .. Based on the Karl Rothammel and ARRL Antenna Fundamentals
1 - Type
the desired center frequency fC in
2 - Type
the desired radiator outer
diameter d in mm. You
have to know that d : D is between 1 : 3 and 1
: 4. D is the inner diameter
of the tube. It is possible to calculate from radiator to
tube or from tube to radiator : click here
and scroll to VHF UHF SHF spertop.
3 - Type
the factor V, if you do not know it,
click the input, now the value 0.94 disappears, and then click the
4 - (
A ) Now, the calculation delivers
the so called 'Schlankheitsgrad'
( and already
the ChassisPart Height too ). Now you will find easily the V factor,
use the diagram above. Click on it.
) Type ( the found value, input factor V
) and click the Calculate Button again.
: fC = 1280 MHz, d = 6 mm, factor V = 0.94 => you find the
correct values. The Advised Total Length is the required length
of the inner conductor to attach easily
the antenna to a mast.