Receive only comment.
A low dipole - 15 feet average, uneven ground - Receive Only - accounted for something like 40% of the
contacts with NA from XZ0A. During the first 2 hours at Sunset, the low dipole heard signals that the
admittedly not all that good beverages could not hear at all. Site had a pretty good noise floor for
Asia. on an island on Diesel power.
This was during a higher portion of the sunspot cycle so the polar oval was quite large preventing most
of NA from having a clean direct path. Our signal - 1500W into a elevated radial elevated feedpoint
full size quarter wave tower - was invariably heard via the SW path when heard east of the Midwest. so we
were dealing with ducting and greyline bending.
the point is - again - you can never have too many receive antennas. An NVIS receive antenna can
significantly benefit your receive capabilities. YMMV especially based on location. Equatorial regions
seem to benefit more from NVIS RX and or Horizontal polarization.
On Transmit it appears the ground absorption negates the benefits for longer haul paths where better
efficiency is needed - until you get the dipole high enough to stop heating the gophers.
Robin WA6CDR
XZ0A-XZ1N, etc
----- Original Message -----
From: "Wes" <wes_n7ws@triconet.org>
To: <topband@contesting.com>
Sent: Sunday, March 15, 2020 13:03
Subject: Re: Topband: NVIS Antenna
When I decided on the new challenge of working DXCC on 160 for my ninth band, I added some extensions
on my 80-meter inverted-vee , (apex at 45') and tied them off on some handy saguaro cacti about head
high. You don't climb these :-) I worked my first 80 or so countries with it. And this is from southern
AZ, not Maine. K3S + KPA500.
Wes N7WS
On 3/15/2020 12:47 PM, Carl Luetzelschwab wrote:
For those who are antenna challenged, don't sell a 160m inverted-vee at low
height too short.
My 160m antenna at the moment is an inverted-vee at an apex of 45 feet.
Additionally, the last third of each end is at 90 degrees to the main
portion and horizontal at only 7 feet or so off the ground. It's what fits
on the property.
In the CQ 160m CW contest in January 2017. I came away with 44 states
(missed ME, ID, NE and AK), 7 Canadian provinces (VE9, VY2, VE2, VE3, VE5,
VE6 and VE7) and 17 DXCC entities (mostly Caribbean, Central America,
Mexico and South America, with a few Europeans, a North African and a KH6
in the mix). I was seldom #1 in a pile-up, but eventually I usually got
through with 800 Watts to the inv-vee.
It's better than no antenna.
Carl K9LA
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