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

[Ted KT1V]

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!)

73
Ted KT1V
Ted Demopoulos KT1V
Demopoulos Associates, www.demop.com
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
 >
 > _