The "wet" numbers represent worst case
for lines covered with ice or snow.
Here's a quick line loss calculator to use Note that
the simple program used for this web page gives a very close approximation for
additional losses due to SWR.
Set Parameters as Desired
Line Type:
Line Length:
Feet Meters
Frequency:
MHz
Load SWR:
: 1
Power In:
W
Results
Matched Loss:
dB
SWR Loss:
dB
Total Loss:
dB
Power Out:
W
Online Coax Cable Loss /
Antenna Gain Calculator
This program is provided "as-is". It is thought to
be accurate but it is the responsibility of the user to verify the accuracy of
the calculations when using this program.
Formulas To Design Your Own Dipoles And
Inverted Vees
INTRODUCTION-The longwire antenna is a very effective antenna for the
listener who wants to cover all of the shortwave bands from 530 KHZ to 30 MHZ.
However if you have some favourite frequencies that you listen to on a regular
basis you may wish to consider a dipole antenna. This antenna is a fairly easy
to construct antenna and will give you better reception on the frequency it is
cut for. Think of a dipole as a longwire that has a insulator in the
middle.
FREQUENCY-A dipole antenna will not only work well on the
frequency it is cut for, but also for the multiples of that frequency. For
example if you cut a dipole for 7.0 Mhz will also work well on 14 Mhz, 21 Mhz
and 28 Mhz. This way if you can pick and choose your frequency you can make one
antenna work on two or three bands.
LENGTH- To find out how long the
antenna should be all you have to do is fill in a simple formula:
468
divided by FREQUENCY IN MHZ = LENGTH IN FEET 300 divided by FREQUENCY
IN MHZ = LENGTH IN METERS
That is the only formula you need ever
know to build a dipole antenna.