[Top] [All Lists]

Re: [TowerTalk] 80m Newbie...Help w/ Inverted V Please

To: Tower-Talk <>
Subject: Re: [TowerTalk] 80m Newbie...Help w/ Inverted V Please
From: Ted KT1V <>
Date: Mon, 04 Oct 2004 06:44:33 -0400
List-post: <>
I had a 160m inverted V which due to trees etc. had one leg very close to a guy wire. No matter what I did, the SWR min was about 4:1.
I suspect coupling to the guy wire, but importantly IT WORKED OK. I worked plenty of DX with my 4:1 SWR and friendly ACOM amp which was happy to still put put a KW or so.

As a side note on 80m, my first 80m ant was an inverted Vee at about 30 feet. Working EU was close to impossible. I raised it to 40 feet and EU was very very easy to work (obviously from the East Coast - hi!)

Ted KT1V
Ted Demopoulos KT1V
Demopoulos Associates,
Aligning Information Technology with Business Objectives.

Robin Midgett wrote: > > Hi, > My attempts to make an inverted V resonate on 80m are not meeting with > great success. I've put up inverted V antennas before (10m & 40m) and they > worked very well...not so in this case; 2.8:1 (feed point fully up) is the > best match I've seen yet. I'm hoping some of you more experienced will have > some constructive input. > Here's the configuration: > 130' of Rohn 45G, on fairly flat, level ground with a 24" (out from the > tower) aluminum stand off bracket at the 60' level. A rope and pulley rig > is used at the end of the stand off to haul the feed point of the V up to > the 60' level. Each leg of the V is ~62' long, and there is ~ 80-90 > degrees between them. The ends of the wire (14 ga. stranded) are formed > into a loop, which is where a small piece of rope attaches and anchors to a > stake in the ground. Pretty typical stuff, from all I've seen before. > The tower is guyed at 30' intervals to posts 85' from the tower base, so > guy wire lengths (all 1/4" EHS) are 90', 104', 124' & 127', no insulators > on any of them. > With the feed point pulled up all the way, ~3:1 is the best match I get. If > I lower the feed point to ~50', and the ends of the wires are drooped onto > the lawn, the match improves to ~1.8-2:1. > I'm using a MFJ-269 to make the measurements. I find really good matches > (~1.5:1 or better) at 12 MHz, and odd multiples up the bands. > I've changed the coax, no help. Removed the coiled coax choke; no help. > Checked continuity from shield to end of one wire, OK; from center pin to > end of the other wire, OK; no shorts, either. > Is this possibly a case of guy wire coupling/interaction? Might raising the > feed point to a higher level help the match? Should I extend the distance > from the side of the tower to the feed point? > Thanks, > Lost in H.F....going back to VHF+....Robin KB4IDC > > "Success is the ability to go from failure to failure with no loss of > enthusiasm." -Winston Churchill > > _


See: for "Self Supporting Towers", "Wireless Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions and ask for Sherman, W2FLA.

TowerTalk mailing list

<Prev in Thread] Current Thread [Next in Thread>