I put up a 1/2 wave Inverted V ( each leg is about 140' ) for 160M in January
of this year just so I could do inband SO2R in the CQ160 CW contest. It has its
apex at 40' and the ends are at 5'. I would have been very happy to just work
any East coast stations during the contest but I found that I was being called
by stations from as far away as California down into the Caribbean and
everything in between.
This morning I worked Luke ( VK3HJ ) on my Inverted L here at 1110z ( SR-5 min
) and we exchanged Q5 reports - nothing unusual. Then at SR he disappeared
into the noise. Again nothing unusual. After a java refill I came back into the
shack and could hear NA stations calling and working him but he was still NIL -
not even a single ping could be heard on the Inverted L. Just for fun I
switched over to the Inverted V and there he was 539 to 549 - a real booming
signal almost as loud as when we worked earlier when I gave him a 559 on the
Inverted L. Now it was SR+28 min so when there was no one coming back to his
CQ's I called and I almost fell out of my chair when he came back to me. No we
didn't make the QSO as he didn't get my full call but the fact that he heard
anything is amazing. Had I been running more than 100 watts I have no doubt we
could have finished the QSO.
So the Inverted V definitely stays up.
Carl I am a believer :-)
73,
Brian
VE3MGY
________________________________
From: Topband <topband-bounces@contesting.com> on behalf of Carl Luetzelschwab
<carlluetzelschwab@gmail.com>
Sent: March 27, 2018 2:49 PM
To: topband@contesting.com
Subject: Topband: low inv-vee
Pete N4ZR said one option was to "Suspend inverted vees for 80 and 40 from
the top of the rocket launcher (right under the tribander)."
Gene AD3F commented on low inv-vees: "From what I've read on Topband and
TowerTalk over the years, a low Vee as you're proposing is likely to be a
cloud warmer."
Yes, a low inv-vee will radiate more energy at the higher elevation angles.
But it still radiates energy at the lower elevation angles that are useful
for longer distance contacts. For example, a 160-Meter inv-vee at an apex
of 45 feet is about 10 dB down (approx 2 S-units) at an elevation angle of
15 degrees compared to a quarter-wave vertical over average ground.
For the CQ 160M CW contest in January 2017, I used a 160-Meter inv-vee at
45 feet, with the last third of each end running horizontal and bent 90
degrees from the main portion to fit on our property. Yes, it's a
compromise antenna, but I worked 44 states (missed ME, ID, NE, AK), 7
Canadian provinces and 17 DXCC entities (mostly Carib, Central Amer and
South Amer, with some EU and a North Africa). My amp at 800 Watts certainly
helped, along with a Shared Apex Loop array for receive.
I wasn't first in most pile-ups, but perseverance got the job done most of
the time. So don't count out a low inv-vee if you have trouble putting up
something better. The inv-vee is relatively easy to erect and it's
efficient in terms of not needing a ground system. Of course an 80-Meter
inv-vee at 45 feet will be better than a 160-Meter inv-vee at 45 feet, as
it's twice as high in terms of wavelengths.
Carl K9LA
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