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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