This antenna, or that one?

[KD6VXI]

Just finished up my ladder line, homebrew.  6 inch spacers, #10 gauge, 5 inch effective spacing (I drilled through, and ran the wire THROUGH the insulators, then zip tied to keep in place),  About 62 feet.  This will be fed into a Johnson Mini Matchbox.  It's what's I gotsted now...

I built 2 years ago a full sized 160 dipole, intending to do a K1JJ tuna, but that isn't happening as fast as I'd like, and I'm tired of 100 watts PEP.  SO, what to do, what to do?

The mini matchbox doesn't do 160.  So, that's a moot point, at this time. 

I'm considering one of two antennas, either a 160 inv V, fed at 42 foot apex.  I have 11 acres to bring the ends down as far as I can, BUT, I'm on a 6K foot mountain peak, and only have about 30 feet to each side of the tower, then the mountain rolls off QUICKLY, about a thousand feet to one side, and about 2000 to the other.  The ends of the V would be straddling my peak.

The OTHER config is a full sized 80 loop.  I CAN run it with it fed on the west end, and then use the north and south sides (which are the ends that fall down the mountain) pulled down to the fenceposts, and I do have the capability of putting up about a 30 foot 'mast' (old radio shack pole).  With the loop, I can also use it as guy wires, although I could with the inv v as well.

So, since my tuna DOESN'T cover 160, should I go with the loop?  We do get HORRENDOUS amounts of ice up here, as I posted with the 10 meter vertical snapping (the mfg custom designed a new one for me, no charge.  THATS customer service.. Eventually it will be put back atop the tower, but for now, it's sitting in the garage).

I left ALL the insulation on my wire.  I've been told that this can help lower precipitation static.  The loop also being a closed system, I'd have less noise on it, I believe.  I could eventually feed it some DC to keep ice buildup down as well... BUT, is it the good antenna I need? 

Those that have played with both, ideas?

Thanks....  Cleanin up the plastic mess in the driveway now, probably erect the antenna portion tomorrow, so I have a bit of time for planning..... 


--Shane
KD6VXI

[K1JJ]

I'm considering one of two antennas, either a 160 inv V, fed at 42 foot apex.  I have 11 acres to bring the ends down as far as I can, BUT, I'm on a 6K foot mountain peak, and only have about 30 feet to each side of the tower, then the mountain rolls off QUICKLY, about a thousand feet to one side, and about 2000 to the other.  The ends of the V would be straddling my peak.

Shane,

Just thinking outa the box for a moment...  being near Bakersfield, Calif, is it possible to pull out those legs, like 1000' per leg in the direction of east to form a V-beam?     Since most activity is to your east, you would cut down receiver noise to the west (f-b ratio) from the ocean storms too.  If the terrain falls off sharply enough, then you might be able to get a tremendous average height and very good low T.O. angle.

The other alternative is to hang a 40' boom (or longer) or rope support from the tower top and hang a pair of inv vee phased dipoles that are fixed east. That would work like a bomb out east with your big terrain drop-off. This would be for one band, however, unless you interlaced two bands.

With your location, I wud try for those ideas first. Go for some gain and f-b. If not, then consider a high inv vee fed with opewire as third choice.

Either way, with all that room, run a Beverage receiving antenna to the east too.

T

[KL7OF]

For 160 have you considered a resonant antenna fed with coax?...No tuner needed......

[KD6VXI]

Tom,

Originally I had though of that.  Problem being, I have about another 800 foot of mountain due EAST, to the tune of about a city block.  Couple that with the fact that's the direction of the power lines, and I was afraid of having to have LOTS of powerline noise.  Had that in Nor Cal to the point of making me put the radios in the box for a year.  HOWEVER, I am running a rotatable V beam on 2 meters and 440  

The property here runs 11 acres, but it's on the south slope...  Facing Los Angeles.   Not having used a beverage before, would the be directional broadside?  If so, that would be ideal, as the mountain slope due east of me falls off faster that direction, and I could get some REALLY good receive that way.

I think I'm going to try the Inv V for now.  Actually, the antenna center insulator and line is pulled up, and the towers extended In the 20 minutes since I had to go get the boys at the busstop, the weather has taken a REAL dive.

The more I think about it, 160 is kind of a dead issue.... With an SB220, a Harris RF103 (2-30 mhz) and a Johnson Mini Matchbox.....  What's the point for 20 watts carrier? LOL


Thanks!

--Shane
KD6VXI

[WA1GFZ]

I never heard much activity below 40m when I lived in LA. Most yards are too small for large antennas.
There is nothing magic about building an antenna tuner.

[K1JJ]

" Not having used a beverage before, would the be directional broadside?  If so, that would be ideal, as the mountain slope due east of me falls off faster that direction, and I could get some REALLY good receive that way."

Shawn,

The Beverage is directional in the direction it runs, much like a true "longwire".  But if you ran it for 600' long about 6-7' off the ground, hugging the terrain elevation, it would work fine. Terminate it eastbound. You have poor, rocky ground there, right? A bev works best with poor conducting ground.  Hopefully the peak you mentioned in the distance is low enuff not to significantly block any usable low angle signals.

T

[W1UJR]

Easy to make a Matchbox play on 160, do that here with an external padding cap, works like a charm!

[KD6VXI]

My terrain is DG, or Decomposed Granite.  Rocky soil would be an upgrade

We DO have a nice layer of topsoil, for some reason, but about a foot down, ground rods get REALLY interesting to put in.  No clay, but some very interesting layers below me.  Elevated ground planes work AWESOME in this area, and I've found a real ground fairly elusive, another reason for going balanced.

I have a spool of about 500 feet of wire left...  I'll have to give a bev a try, see what I get.  When I had the elevated GP for 80 up, it tuned all bands, and I couldn't find any REAL dead spots....  Perhaps owing to high angles from my crappy ground?, but it worked well enough with 100 watts to snag a lot of dx, throughout the world....  Except West Africa, I could never even hear them.

Ran out of daylight and weather today, but got it generally laid out.  The ends are going to be really low, 20-30 feet above immediate terrain.......  BUT, that works out to probably 70-80 feet BELOW the feedpoint (at the apex of the 40 foot tower)... I'm expecting a bit of directionality... =

--Shane
KD6VXI


And Frank, no a tuna isn't rocket science...  The parts I have are QRP, and it isn't looking like any QRO are falling into the lap.  Funds tight, so using what I got.  This IS a step up from the remote tuna 100 watt setup tho

[Steve - K4HX]

Don't sweat it. Run what ya got, make improvements as you can. It's all part of the fun. Good luck.

[WA1GFZ]

The subsoil is like old concrete. I helped a friend dig a trench to run power to his little fish pond. I was swinging a pick ax. A chip came off the point and landed under my skin of my upper arm.

[KD6VXI]

Franks right, when we have GOOD soil here, it's ground up concrete.

Hoisted the antenna up in the air.  One side is about 5 feet off the ground, and 15 feet below the base.  The other side is about 35 feet BELOW the base of the 40 foot tower. 

First contact was Michigan, on 18 mhz.  Pointed the OPPOSITE direction of the V... It has a slight angle towards the pacific.. :/  Had to do that the way the guys where arranged, I wanted the ladder line to follow the guy in that was phillystran...  I had one phillystran break, and had to replace it in a pinch with standard galvanized guy wire... 

So far, so good.  WAY better signals than the vertical, at least stateside.  Should be interesting to see how it performs vs the vertical into other hemispheres...

Incidentally, STILL running through the external marine tuna, but ladderline out of it to the dipole.  Going to have to make up a plate to bring the ladderline into the house... LOL.. COMPLETELY forgot about that part.  From what I've read, since I have approx 5 inch spacing, 5 to 6 inches away from the coaxial cables, correct? OR, should I use stubby coasshole pieces to take it outside the winder?

Thanks for the help thus far...  Just the new antenna was like 20 dB.  I'm going to make the assumption it will be even better when I have the ladder line routed AWAY from the roof, the eves (no gutters here, but we do have metal flashing), etc.  Shoot, one feeder is about an inch from the old elevated radials.  Lots of wire to spool back up here lol.....  Course, my 7 year old just finished his first crystal radio, maybe I'll let him take a walk through the trees and string up his antenna with the old wire

--Shane
KD6VXI