Antenna Location Thoughts

[Carl WA1KPD]

I am thinking of relocating my antenna and wanted some input.

First off, on HF I work mostly 160, 80 and 40. Our lot, which is heavily wooded is about 200' by 400' deep. Over the years I have generally run a G5RV on 80 up and a dipole on 160. Both antennas are fairly close to the house and over the 16 years we have been here, the hash and crap has gotten worse, as it has for most of us.

One option I have is to put the antennas about 300 feet away from the house. This also puts them farthest away from the neighbors and up against a state forest for which there is no one for about 3 miles. The down sides are:

• They would favor east west. Currently they favor NE/SW which for southern CT is great
• There would have to be a long coax run, about 250 ft additional
• The antennas would be about 15 feet lower and shooting onto the trees to the west because of topography

It is fairly dense woods so I would have to bring down some large trees. But to get rid of the noise, including the QRN that has ridden in on the power/cable/phone lines for years, it would be worth it.

I'm looking for some thoughts as to if that is worth all the trouble (subjective) or if it will most likely not really solve my issues.


Thanks for the knowledge/experience

Carl
/KPD
 [/list]

[KA2DZT]

My antennas are in the woods not all that far from the house.  I don't pick up much noise from them.  Although, our services are underground which helps a lot.

Fred

[flintstone mop]

The trees do not seem to affect antennas. As causing absorption of RF.
EWES and loop antennas and long beverages get directional in the Receiving world.
How high are you planning to raise these antennas??? 160M and 80M need to be at least a 1/2 wavelength high before you have a directional pattern..............most, if not all, of us are mainly using cloud warmer antenna systems. Now at 40M the job is easier to get some directional pattern
As for length of feedline, use RG213 that can be buried. Or get a hold of some used CATV cable and a balun at the shack end and the losses will be reduced. It's not that many dB of loss at 160 and 80 M, even at a high SWR. Even a 5:1 SWR is not a problem at 160M and 80M.........20 and up starts to be big losses. 6M and up it gets serious.......2:1 is the hairy edge at those freqs.
OWL will tolerate high SWR and the losses are negligible, even very long runs. It has to be managed better than coax.
And you are on a good track to get the aerials far from the QTH and the neighbors.
Much less RFI to worry about and the noises and buzzes are almost gone. My rule is 100 feet minimum from the QTH and the neighbors. I know many here are dealing with small lots and many times causes conflict.
Fred

[Jim, W5JO]

Don't worry about the trees.  You may have to adjust the length of your antennas a bit, but they won't absorb enough to worry about.

You will be gaining a lot by lowering your noise level from household appliances and such.  If you are concerned about coax loss the pick up some 1/2 inch hard line.   I have been seeing a lot of new rolls showing up at hamfests down here almost as cheap as new 213.

[W0BTU]

I agree, don't worry about either the trees or the long coax run. For those bands, they are not going to hurt you.

Getting your antenna away from the house, you'll likely pick up less noise.

Have you considered an inverted-L? I had one with two elevated radials on 160, and it worked fantastic.

And do consider a Beverage, even a short one. http://www.w0btu.com/Beverage_antennas.html You'll hear a lot more on a Beverage!

[ke7trp]

I dream of being able to move the antennas away from the house and neighbors. Go for it. 

ALOT of noise can be tracked and eliminated.  A small SW radio tuned 40 meters and a walk around the house will probably be eye opening.  Todays Cell phone chargers can put out one hell of a Noise on the Ham bands, even if its not charging a phone. DVD plays while OFF will also do the same.  Certain brands of CFL bulbs.. and the worst are some reading lamps. When the lamp is switched OFF, there can be one hell of a noise on the bands.  Good luck

C

[aa5wg]

Carl:
I used an 80 meter center fed dipole fed with open wire line in the trees for several years.  It performed well.  The trees were so thick you could not see the antenna in the summer months because of the leaves.
Chuck

[flintstone mop]

Mike Said:   Have you considered an inverted-L? I had one with two elevated radials on 160, and it worked fantastic.

I forgot about that antenna..........VERY good choice. Very versatile. Making the vertical part at least 60 feet will be a good DX antenna for 160M and the horizontal part for the local (at 500 mi) contacts. Antenna tuner at the base, it would be great for 160-20M. The higher bands would have too many lobes and then you are dealing with directionality.
Typically you use a Yagi for the upper bands, mounted about 35 feet (min) off the ground.
60 foot high Yagi is a little over-board.

Many Arborists (tree workers) will install the antenna wires for you, if your tree cover is thick and you have to "weave" the wire through the canopy. Give your antenna(s) a lot of sway room when the storms hit this Winter.....Strong Marine pulleys and weights on the ends of the antenna wires to allow for the swaying trees, and your antenna system won't break.
Fred

[K3ZS]

I had the same problem, and the solution getting away from the house noise was to put the antenna far from the house.  However, you should use ladder or window line to keep the losses low, and feed it with a well balanced tuner.    Having used an MFJ tuner with a crappy balun, I still picked up house noise on the feedline.    Using a better external balun got rid of the house noise.   A true balanced tuner would be the best, and using real ladder line would be better than the window line.    The window line requires retuning and has a higher loss if it is wet.
I use a 135 ft doublet, in parallel with a 16 ft.   The short element provides an almost dipole pattern on 10M, the other element works good on 80 and 40.   The other bands can used also.

[K1JJ]

•The antennas would be about 15 feet lower and shooting onto the trees to the west because of topography

I read this to mean the antenna will be at the same height above ground, but positioned DOWN the hill from where it is now?
If so, then that will be OK, since for local work a "moon crater" effect is actually good for high angle enhancement.

If the antenna will be 250' farther away, in the clear, then by all means do it. A quiet receiving antenna (and transmitting with minimum RFI) is a worthy goal. The east/west orientation will have little effect at tree height on 160-75M and the extra cable wil be insignificant too. (40M may see some pattern sharpness) Do try to get a length of hardline or some common 75 ohm aluminum CATV line. It works very FB. Later on you can use a master relay out there to remotely switch in all sorts of higher freq antennas with minimum feedline loss. (6-20M, etc)

T

[WA1GFZ]

I would not move the TX antennas but put up some low noise RX antennas.
I like loaded delta loops.  You can also phase multiple loops. I find a 30 foot base with the apex 15 above the base works well up to over 10 MHz. I use a 1k load resistor and a 4:1 BB transformer to coax. A string of common mode beads on the coax. I like the base at 5 feet or so with the apex up about 20 feet. Dallas Lankford has a lot of data on phased loops. I'm also going to be putting up 4 phased e probes soon to compare performance.
Presently I have 1 loop facing west and one facing East.
You also might consider a beverage or two if you can get a good run of wire in the right directions.

[Carl WA1KPD]

Thanks for all the input. I moved the antenna back into the woods so close the end of the G5RV is about 100 ft away from the house and into an area where this puts it maybe 700' behind and 45 deg away from any other houses. Other side is clear for several miles of state forest.

Have not transmitted on it yet, but HUGE difference on rcv. Line noise, most part 15 noise etc is gone.

Now to get the 160 mtr antenna up.......

Thanks all
Carl
/KPD

[Jim, W5JO]

Carl do an inverted L for 160.  That and enough radials to get the impedance near 40 ohms and you will have a good antenna.  I regularly work a guy in AZ that has a folded unipole with a good radial system and he works the world with 100 watts.  Use that space for something really productive.   

[Steve - K4HX]

I agree. If it's about receiving, just put up some RX antennas out in the woods. This way you get the best of both worlds.

I would not move the TX antennas but put up some low noise RX antennas.

[K6JEK]

I would not move the TX antennas but put up some low noise RX antennas.

What he said. You're making some of us jealous with numbers like 300'.

I've had some success with small, phased receive loops.  You can build a tuned home-brew one for next to nothing but I ended up augmenting with a Wellbrook 1530 which I happened across for a reasonable price.  They have very deep nulls broadside.  I aim them at the worst noise source then phase to further improve S/N.  I've become a fan of RG-6 and CATV high-quality F connectors for receive antennas.

As much as I like the phased loops if I had the room and maybe you do, I'd put in a Beverage or two.

Do you like the G5RV for TX?  If I had that much space to work with, I guess I'd be thinking about full sized dipoles and if I could swing it, phased dipoles, as in K1JJ's possibly the best 75 meter antenna.  I think that's what Tom calls phased dipoles.  I've had 'em and they were great.

[K5UJ]

What's a Wellbrook 1530?  What band do you use it on?   I have been thinking about phased loopsticks for 160 m.

[K6JEK]

What's a Wellbrook 1530?  What band do you use it on?   I have been thinking about phased loopsticks for 160 m.

The Wellbrook 1530 is a one meter diameter broadband receiving loop from England, pre-amp at the antenna:

http://www.wellbrook.uk.com/ALA1530.html

They've been making these for a long time.  Once in a great while they show up on eBay over here in the colonies.

There is now some American competition:

http://www.pixelsatradio.com/product/shortwave-magnetic-loop-antenna/

There is a long but interesting video on the Pixel site.

You can find a few Wellbrook vs Pixel reviews with commentators landing on both sides. I haven't found a definitive review.

Neither is cheap. What is cheap is the home-brew Doug DeMaw loop straight out of the ARRL Antanna book. At least it's in the old, 2003 edition I have. I built one for nothing and liked it so much I built another. But it is single band and tuned. Where it's tuned and used with a low noise pre-amp it's just as good as the Wellbrook. Elsewhere it's deaf as a post.

I've used the Wellbrook only on 160, 75, 40. Right now I'm trying it out on 10 where so far I'm not impressed. The tuned loops are 75 only.

I have the expensive DX Engineering phasing unit which is an excellent unit.  I used an MFJ 1025 for years which was OK at a fraction of the cost.

[Carl WA1KPD]

I would not move the TX antennas but put up some low noise RX antennas.

Do you like the G5RV for TX?  

For about 15 years now I have run a G5RV on 80-10 and a full sized dipole on 160. I have been very happy with the G5RV and get good signal reports.
Back to the original topic, before I moved the antenna, rainy or foggy nights made listening unbearable with with the ambient line noise. Getting the antenna away from the house made all the difference. We had a very foggy night Tuesday and pouring rain last night and not a QRN was to be heard.

However now I do hear at least one electric fence, that used to be covered up by the QRN Not surprising because I have a number of small horse farms in the area... I'll live with it. I wonder how they make it past part 15???

[ke7trp]

Have you considered using a static bleed on the antenna?  This really took the noise level down on windy nights here in AZ

[KL7OF]

any chance of stealth rx antennas in those woods behind the house?    A beverage on ground under the leaves makes a great low noise rx antenna