Installing An Nvis Kit With A 3040 Automatic Whip Antenna; Figure 8: 3040 Antenna With Nvis Kit - Codan 3040 Installation Handbook

Installing an NVIS kit with a 3040 Automatic
Whip Antenna
NVIS extension
section
angle
adaptor
riser
Automatic Whip Antenna 3040 Installation Handbook
An NVIS kit (Codan part number 78-14010) is available for
attaching to a 3040 antenna. For information on installing this
kit with the antenna see the instructions provided with the kit.
The NVIS kit is designed to improve the performance of short
to medium-range HF communications for the 3040 antenna by
increasing the high-angle radiation characteristics. Typically,
these communication distances are 20 to 500 km (12 to
310 mi). The operating frequency range when using the NVIS
kit is 2 to 12 MHz.
The vertical radiation pattern from a short vertical whip
antenna is very poor. As such, HF communications over short
distances may be difficult or non-existent from such an
antenna. The NVIS kit lengthens the whip section of the 3040
antenna. The NVIS whip is longer and positioned horizontally
to improve the vertical radiation efficiency.
Figure 8: 3040 antenna with NVIS kit
direction of
propagation
of skywave
1 m
Installing the antenna
top stainless steel
whip section
tie-down
cord
roof gutter
clamps
21