Somewhat about technique of VARYLINK
31st December 2005

It is a well known fact that the radiation resistance of an
antenna varies strongly with the height above ground.
According the ARRL Handbook, chapter "antenna fundamentals"
the radiation resistance of a dipole varies in the range
between 20 to over 95 ohms for height from 0.1 to 0.5
wavelength above ground.

The VARYLINK allows to adjust continuously the perfect
match between the feeding coax and the input impedance
of the antenna. This way one reaches an SWR of 1.0 at
resonance, independent from the installation height.

The VARYLINK is part of the antenna in my design and
allows a perfect match at practically no transformation loss.

The following advantages result in the operation of the antenna:

- No "stray radiation" and therefore prevention of RF
   interference into transmitter.
- Highest efficiency and linear operation of the final power
   stage of the transmitter.
- Minimal losses in the feeding coax line to the antenna.
- Prevention of standing waves and radiation of the feed line.
  This prevents BCI and TVI, and assures a clean radiation
   pattern.
- Contribution to highest efficiency of the antenna.

Now in a short time we will have the construction guide.
During January/February I am travelling, coming back
in March.
Then we are ready !

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