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NQ6U
03-05-2013, 10:16 AM
Finished up my new Field Day antenna well ahead of the actual date for once. It's a wire Moxon beam for 15m and the whole thing can be carried and erected by one person. I wouldn't want to lug it up a mountain or anything but since most of the weight is in the surplus fiberglass camouflage netting supports I'm using for masts, it would be easy to shed weight by using a pair of lighter poles.

Here's a picture of it collapsed for transport:

http://i815.photobucket.com/albums/zz79/gyrogeerloose/FD-Moxon-stowed.png

It stands about 20 feet tall when it's set up, and is about 17 feet long by 6 feet wide. That's about 6m x 5m x 2m for those of you in the more civilized countries.

W4GPL
03-05-2013, 10:28 AM
What are you doing talking about ham radio stuff!? We don't do that here.. :-P

NQ6U
03-05-2013, 10:36 AM
What are you doing talking about ham radio stuff!? We don't do that here.. :-P

Oh, okay, sorry. How about this:


"Obama is a socialist Muslim atheist from Kenya"?

NQ6U
03-05-2013, 10:39 AM
By the way the whole thing cost less than $40 including the mast sections and old Bencher 1:1 balun, the latter of which I bought on eBay for six bucks.

W4GPL
03-05-2013, 10:44 AM
By the way the whole thing cost less than $40 including the mast sections and old Bencher 1:1 balun, the latter of which I bought on eBay for six bucks.How much of that $40 was Obama's outrageous taxes?! ;)

Neat though. Let us know how it performs..

KC2UGV
03-05-2013, 11:13 AM
Where did you get the camo poles at? Or, are those something else for the mast?

NQ6U
03-05-2013, 11:54 AM
Where did you get the camo poles at? Or, are those something else for the mast?

There was a local guy selling them for a buck each a few years back. Unfortunately, they're harder to find nowadays. These are what I had left over.

X-Rated
03-05-2013, 11:58 AM
Moxons are great antennas on my antenna software. Will this be horizontally polarized or vertical? At what height? And my final question, will this antenna withstand the new lawful federal domestic wiretapping actions since there is wire involved?

NQ6U
03-05-2013, 12:18 PM
How much of that $40 was Obama's outrageous taxes?! ;)

$39.98


Neat though. Let us know how it performs..

I tested it out this weekend. Non-scientific, seat-of-the-pants measurements seem to demonstrate at least some gain over a dipole and the Moxon's characteristic high F/B ratio.

NQ6U
03-05-2013, 12:24 PM
Moxons are great antennas on my antenna software. Will this be horizontally polarized or vertical? At what height? And my final question, will this antenna withstand the new lawful federal domestic wiretapping actions since there is wire involved?

I became a big fan of Moxons after a fellow ARC member and I used 1/2" copper pipe to build one for 20m two years ago. We took it to FD and despite the fact that it resembled the aftermath of a boiler explosion, it rocked!

It's going to be horizontally polarized and as far as the wiretapping thing goes, they can have my antenna when they pry it from my cold, RF burned fingers.

KC2UGV
03-05-2013, 01:03 PM
There was a local guy selling them for a buck each a few years back. Unfortunately, they're harder to find nowadays. These are what I had left over.

Make sure you guy the poles, if you want them to last. The necks crack on them if there is a lack of support.

X-Rated
03-05-2013, 01:36 PM
I became a big fan of Moxons after a fellow ARC member and I used 1/2" copper pipe to build one for 20m two years ago. We took it to FD and despite the fact that it resembled the aftermath of a boiler explosion, it rocked!

It's going to be horizontally polarized and as far as the wiretapping thing goes, they can have my antenna when they pry it from my cold, RF burned fingers.

How high up there will your fingers be if they are on the antenna getting RF burns when the feds come to confiscate your Moxon?

NQ6U
03-05-2013, 02:12 PM
Make sure you guy the poles, if you want them to last. The necks crack on them if there is a lack of support.

Yeah, I've had a few break that way. It's guyed adequately for the 24-hour duration of FD. I'd add more if it was going to stay up for a extended period through bad weather but the stress on the poles is mostly in compression so it should be fine.

K7SGJ
03-05-2013, 04:12 PM
Are you going to have an erection party?

KG4CGC
03-05-2013, 04:17 PM
Are you going to have an erection party?

A bunch of olde phartes, gathered together in a nursing home room, wearing party hats, cake, one guy in the bed trying to sprout a tent pole and the other guys all cheering him on.

K7SGJ
03-05-2013, 04:22 PM
A bunch of olde phartes, gathered together in a nursing home room, wearing party hats, cake, one guy in the bed trying to sprout a tent pole and the other guys all cheering him on.


And in walks Nurse Melissa in her birthday attire.

The old guy in bed says

The pole is up
the tent is spread
take off your cups
and get in bed

To which she replies

Take down the tent
put the pole away
The monkey had a hemorrhage
no circus today.

N8YX
03-05-2013, 05:08 PM
And in walks Nurse Melissa in her birthday attire.
...
The monkey had a hemorrhage
no circus today.
That's a bad monkey. It needs spanked.

Segueing back into the antenna component of this thread:

I got hold of a few bags of the military mast - both fiberglass and aluminum - over the years. 8 4' sections of the aluminum stuff makes a nice 40M vertical. A Moxon or some type of loaded Yagi (such as the design in the 7th edition ARRL Antenna Compendium) allows for working another band simultaneously and makes a nice capacitance hat.

A friend at work sold me enough surplus 40" car antennas that I can build and deploy 3-el loaded Yagis on 10, 15 and 20. There may be enough left over for a 4-5 el 6M Yagi too.

These can be built light enough that the metal mast has no trouble supporting them - and they can be turned via a rope at the end of the boom.

WØTKX
03-05-2013, 05:20 PM
I have a "mixed bag" of aluminum and fiberglass military surplus poles just like that. With four guy rings and a "folding petals" heavy cast metal base. Got the whole thing from a guy that puts them together and sells 'em in CO Springs. Tops out at 58 feet. Just the thing for camping.

Most of the time I've deployed it to heights of 30-40' or so. A home-brew 6 meter Moxon was used at first, but now I pick one band from 20-6 and deploy the YP-1 Superantenna. Which I've had really good luck with, especially on 10 and 12 meters.

PA5COR
03-05-2013, 05:39 PM
I have 12 of these camo poles 4 feet each and fiberglass green, setting them up each neck gets a stainless steel waterhose clamp around it protecting it from splitting, works fine, had it up before my inverted L as helically wound antenna for 160 se piccies at qrz on my page.
That was 15 meters high, guy wires at 13 and 9 meters high kept it up fine in some 60 knot winds...

K7SGJ
03-05-2013, 07:20 PM
This guy runs this add pretty much every week. 12 poles for $25. If it is a good price, he might ship. FWIW

http://phoenix.craigslist.org/nph/for/3657737861.html

X-Rated
03-07-2013, 10:47 AM
This is a great antenna and all IMO for DX and stuff, but field day is a lot of local contacts on lots of frequencies. For many years there was a club near here who ruled the top 1 or 2 slots on 1A, W9TY. The club ended up stopping most of their FD stuff due to politics and the availability of land to operate.

What they used for an antenna was a pair of flat top doublets up about 35 or 40 feet at right angles to each other and a quick switch between the 2. This allows for a relatively good high angle of radiation for the more local contacts.

Next, they implemented top CW contesters who could peak out at 3-4 contacts per minute. With the score doubled on CW over SSB, the score was very good.

SSB operators were pissed that the bulk of the operating was on CW. So the enthusiasm for the club FD station waned and they really all do their own thing now.

But that is neither here nor there. A great FD antenna is a simple setup that can be agile in frequency, band switching, and some directivity.

If you are like me, I am just there for the fun of it and I put together what I damned well please. But if you are serious about optimizing your score, you might consider this pathway for FD. It is a proven solution.

NQ6U
03-07-2013, 12:23 PM
While a Moxon might not be the best choice in most places, it is an ideal FD solution for my location down here in the extreme southwestern corner of the country. Since I'll be interested only in stations in the US and Canada, the Moxon's wide forward lobe lets me cover almost the entire area without needing a rotator. Keep in mind that from here, US stations in the northeast are at what would almost be DX range to you. And since I will be operating strictly PSK-31, my radio will be on one frequency the entire time so bandwidth and frequency agility is not an issue. There will be five other stations operating phone on other bands but none of them are interested in working 15m, which is why I settled on it.

All that said, I am there mostly for the fun of it. My club isn't a serious contender, we just like to have a good time operating outdoors in each other's company. Since the facility we use every year requires that we shut down our generator between 24:00 and 06:00, our ability to compete is limited in any case. It does give us a chance to catch some shuteye, though.

X-Rated
03-07-2013, 05:08 PM
That should work well for you. I tried PSK and I have had little luck with it in the contest. I must be doing something wrong.

Good luck in the contest.

NQ6U
03-07-2013, 05:57 PM
That should work well for you. I tried PSK and I have had little luck with it in the contest. I must be doing something wrong.

Good luck in the contest.

Last Field Day, I easily outscored everyone else in my club. Digital has the same scoring advantage as CW in that each QSO counts as two points.

NQ6U
11-04-2013, 06:32 PM
Bump.

Due to circumstances beyond my control (namely, the usual FD site burned up in a wildfire and my ARC bought a tri-band yagi), my 15m Moxon was not and never will be needed at any future Field Day. Since I hated the idea of all that work going to waste, I just set it up in my backyard this morning and aimed it at Asia. I guess it works because a few minutes later, I made a PSK-31 contact with YD0PPQ in Indonesia--a new country for me.

ON EDIT: Add XU7TZG in Cambodia, another new country.