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[Articles Home]  [Add Article]  

Portable QRP Antennas

from Len, K1LU on January 24, 2007
View comments about this article!


"Editor's Note: Due to the popularity of some of eHam's older articles, many of which you may not have read, the eHam.net team has decided to rerun some of the best articles that we have received since eHam's inception. These articles will be reprinted to add to the quality of eHam's content and in a show of appreciation to the authors of these articles."

Portable QRP Antennas

Relearning what I already knew.

Having been bit by the QRP bug a few months ago, I decided to try a QRP Field Day. The results were a little disappointing. I did some experiments with various table top and tripod mounted "portable" antennas prior to field day, thinking that 'if it works for them it should work for me' and when the band was really open they did work, but everyone wanted to keep QSO's short, a clear indication my signal was marginal.

I decided to try Field Day from my boat, thinking a good lake ground might be the answer. A commercial shortened tripod mounted dipole was pressed into service on the boat but it just didn't work. The QSO's I did make all had problems with drift. Not frequency drift, but drift on the anchor line because the wind/waves always seemed to change the boats orientation by 90 degrees just as I made contact!

I converted the setup to a vertical configuration, and removed one side of the dipole and substituted about 60 feet of bare copper wire, complete with a 9/16 socket (for weight), which quickly went over the side into about 90 feet of water. This seemed to work better than the dipole but it still was not very good.

Under less than ideal ionospheric conditions running QRP with a portable antenna was an exercise in boredom and repetition. After Field Day I decided to use the QRP rig on the Quad, and the results were astonishingly good. That led me to recall the ancient law I had forgotten sometime after my first KW rig was assembled: `It's the antenna, stupid'.

With a camping trip approaching I decided to try and redeem my QRP efforts by carting the FT-817 into the woods with a gel cell. This time, however I brought along the original ham antenna from my novice days about 35 years ago - a simple wire dipole.

With a couple of tries, that 20-meter dipole was up in the trees about 35 feet (you've got to love those sling shot contraptions) and I had a bit of an audience. Soon it was joined by a full size 80-meter dipole, which was too big for the chosen span so one end hung down about 15 feet.

The 20-meter dipole including feedline and string weighs in less than my "portable" manufactured antenna and the 80-meter job is not much heavier. Neither has a balun (too heavy) but both have a couple of RF choke ferrites on the coax, probably more for mental attitude than anything related to physics, but half of success is attitude so what the heck.

After a week of operating with simple dipoles in the woods at QRP power levels, I have only one recommendation to anyone considering camping or backpacking with a radio. Forget the cute antennas. Make yourself a simple dipole, get it up in the air between some trees or carry a portable mast (like the ones sold by World Radio), and you will have QSOs at an astonishing rate.

I filled several pages in the logbook using this setup, had a wonderful time, exposed several neighbors to ham radio (no TVI in the woods either) and had some really nice ragchews into Europe from the El Dorado National Forest in Northern California, and met some great folks on 75.

My advice to travelers is to carefully tune your antennas, use full size wire dipoles, and save your money. The weight difference, especially if you know your target band(s) is non-existent, and can be in favor of the wire dipole. I wish someone had told me this a few months ago!

With just a minimum amount of planning, a dipole or inverted vee can be put up in less time than it takes to cook dinner. If weight is an issue, you don't need multiple feed lines. Just attach a string to the center insulator, and leave the string on one end of each dipole long enough to lower the antenna. Lower the dipoles when you need to switch bands and move the feedline. Yes, I had an autotuner, and I was able to run 20 meters on the 80 meter dipole with my trusty little LDG, but the 20 meter dipole was always noticeably better. (I had two feedlines so switching was fast for comparisons.)

The tuner permitted operation on 40 meters but at 5000 feet the QRM from Asia was so bad the band was unusable. I thought we had 7-7.1 allocated exclusively to Amateur Radio, but I guess not everyone agrees.

Operating with a dipole and 5 watts was very similar to running 75 watts years ago with boat anchors, and every bit as exciting. There was some challenge to it because anyone with a modern station could clobber you, but once you established contact it was generally solid enough for a great QSO. I'm not ready to trash the QRO rig, but QRP under field conditions certainly works, it's reliable, and most of all, it's a darn lot of fun!

73,

Len

K1LU

Member Comments:
This article has expired. No more comments may be added.
 
Portable QRP Antennas  
by NS6Y_ on January 24, 2007 Mail this to a friend!
The wire dipole, up high enough, is a GREAT antenna. However, it's getting it up into the trees that's often a problem.

There's the surf casting rod approach, the slingshot, the bow and arrow, and even the tennis ball launcher. Most are large, expensive, etc. There's also practicing throwing a weight up into the tree, trickier than it sounds.

A friend of mine has tried the slingshot thing, but the reel gets unbelievable rats' nests, and from the reviews here, others have that problem too.

I'd like to make a sneaky little bow that can be assembled, used to shoot the line into the tree, then quickly disassembled and stowed away - bows and arrows are very illegal within most city limits though. And I have not done any work on it.

So, let's talk about how to get that dipole up into those trees.......
 
RE: Portable QRP Antennas  
by W3TUA on January 24, 2007 Mail this to a friend!
Come to Towanda, PA where there seems to be an archery range in most people's backyard here in the borough. ;-)
 
RE: Portable QRP Antennas  
by N5LX on January 24, 2007 Mail this to a friend!
Of course the best portable antenna by far that I have ever used -- bar none -- is the BuddiPole..

http://buddipole.com/

Lighweight 00 robust -- easy to use -- folds down to nothing... and up in less then 2 minutes...
 
RE: Portable QRP Antennas  
by N8BOA on January 24, 2007 Mail this to a friend!
I have a elecraft KX1 with the built in ATU and have operated from Isle Royale twice. I have tried the end fed with lots of ground radials with very poor reselts. What has work very good for me is a non-iverted V stright to the radios antenna BNC connector. No ground loss no feedline loss. Each side is longer then a 1/4 wave to elevate the current node of the antenna. Each time I have kept a schedule with my ggod friend in South Michigan with the V I was 10 over S9 at 3 watts 30 meters when using the end fed he was unable to hear me with his 3el beam up 100 feet. These results were repeated each year. This year I am going to try a dipole with ladder line and a 20f fishing pole.
Have fun
Sean
 
A casting rod with a 1 ounce weight works great!  
by KT8K on January 24, 2007 Mail this to a friend!
After years of experimentation with slingshots, fishing rods, bow-and-arrow, and a pitcher's arm (not mine) I have found what works best for me: a casting rod with open face reel, 20 lb. braided dacron line, and a one ounce weight ... I repeat ... a ONE ounce weight.

I have tried half ounce weights, two ounce weights, and 1.5 ounce weights, and the difference with the one ounce weight is surprising. 1.5 or 2 ounce weights are too heavy for the rod and sometimes break right off the end of the line. They are too big and clumsy to launch well from the slingshot, too. The half ounce weight never got me above about 50', as it just does not have enough mass for the job. A one ounce egg-weight works great, however - I have cast it straight up FAR over the tops of my 100' trees. I can't explain why that particular weight works so well, but it really does. Note that I spray paint the weight blaze orange to make it easier to spot, too.

And, since I like to fish, I have a telescoping aluminum fishing rod that packs under 18" length to take if I'm backpacking. It works almost as well as the 6' one-piece carbon fiber rod. Result: my wire antennas are optimized for height, and my QRP signal gets OUT! The antenna is REALLY the thing.

Best rx & 73 de kt8k - Tim
 
Antenna Shootout  
by KQ6XA on January 24, 2007 Mail this to a friend!
HFpack Antenna Shootout.
Directly compares various antennas for gain/loss, measured in decibels. See the HFPACK.COM website:
http://hfpack.com
 
RE: Antenna Shootout  
by W4LGH on January 24, 2007 Mail this to a friend!
The best QRP antenna I have found, or at least works the best for me is a 51' wire fed with an MFJ-16010 random wire tuner. This is what I used with my Yaesu FT-817 and always had great results! (33 confirmed European countries running <5Watts) I usually try to get the far end of the ant up as high as possible, the tuner is connected right @ the radio with a 12" pice of coax. Its small simple to deploy and as I said worked great for me on 80/40 and 20meters.

Many have seen this work and are amazed at the performance it gives. Have since sold the FT-817 and replaced it with the Yaesu FT-857, and will do the same with it running low power or 100watts.

73 de W4LGH - Alan
http://www.w4lgh.com
 
HF Pack Antenna Shootout  
by KC8VWM on January 24, 2007 Mail this to a friend!

Looks like someone is having loads of fun on QRP, enjoyed the video's:

http://www.youtube.com/groups_videos?name=hfpack

It seems I already have the FT 817 and 22' telescopic crappie pole in stock so I just need to get out and go fishin.

Hmmm... does anyone need a nice QRP fishing hook?

http://www.qsl.net/w0pwe/Finished_Projects/Paperclip_Key/Paper_Clip_Key.html


73 de Charles - KC8VWM
 
Portable QRP Antennas  
by KB3GDD on January 24, 2007 Mail this to a friend!
"A friend of mine has tried the slingshot thing, but the reel gets unbelievable rats' nests, and from the reviews here, others have that problem too."

I've learned (from fishing) that a lot of the tangling problems can be eliminated by removing the fishing line that comes with the reel and replacing it with good quality replacement line. The good stuff does not tangle nearly so easily.
 
RE: Portable QRP Antennas  
by KA4KOE on January 24, 2007 Mail this to a friend!
Use small guage teflon coated wire and build a dipole. If you plan on operating multiband, feed with twinlead to cut cable losses. Of course you'll need a tuner capable of handling twinlead.

This setup used in an inverted vee format really works great with my PRC1099 at 20 watts.

PHILIP
KA4KOE
 
RE: Portable QRP Antennas  
by KB2FCV on January 24, 2007 Mail this to a friend!
When I take my K2 portable, all I use is an inverted Vee. While a dipole configuration would be preferable, when working portable I found the Inverted Vee was simpler to get up in the air. You mainly have to worry about getting the center up as high as you can, then keep the doublets up as high as possible. It sometimes can be a challenge to find enough room to fit a fully stretched out dipole sometimes where an inverted vee would tuck in rather nicely.

I use an old rusty socket and some string and my pitching arm to get the center up as high as I can. After a few tries, I usually get it right were I want it. My antenna is 66 feet long fed with 300 ohm ladder line into an elecraft 4:1 balun plugged right into the back of the rig. Does it work well? I'd say so! 5 watts got me into Switzerland from NJ with good sigs.
 
Portable QRP Antennas  
by K3MOV on January 24, 2007 Mail this to a friend!
The The Alpha Delta Outpost™ Tripod/Ground Coupler Ground Mount System is, I find, the perfect balance between performance and portability. The whole system consists of a 12' Outbacker Vertical Antenna and a tripod which reqires no grounding or radials. The whole thing (antenna & tripod) weighs about 15', but fits easily in a canvas bag I bought at Target for $15.00. It takes about 5 minutes to set up - no trees, slingshots, bow and arrows, balls etc. required. Most importantly, the antenna system works. I have no problem gettting into Europe using SSB on 75 meters. Check out the reviews I think you'll like it.
 
RE: Portable QRP Antennas  
by N6AJR on January 24, 2007 Mail this to a friend!
2 words


FAN DIPOLE :)
 
RE: Portable QRP Antennas  
by AE6CP on January 24, 2007 Mail this to a friend!
I've had em all.
MP-1, Homemade MP-1, Buddipole, Buddistick, Homemade Buddipole, magnetic loop and more variations of random wires, auto-tuners, manual tuners, baluns and counterpoises than I care to remember.

I've used them with my K2, (2)K1's, KX1, NorCal's 20,40a & 38 special, several Rockmites, DSW-II, HW-8, a 1320 T-Kit, FT-817, IC-703+, (2)MFJ-Cubs, and some pure homebrew rigs.

When I finally found THE antenna for use with my QRP rigs, I sold all the others on eBay.

Par Electronics EndFedz dipoles and a spiderbeam 40' telescoping mast. With this you can put up a REAL full sized VERTICAL dipole with the feedpoint at the bottom. Combine this with a hilltop campsite and you will be a very happy OM.
 
Portable QRP Antennas  
by K1YPB on January 24, 2007 Mail this to a friend!
A quick simple antenna I have used with decent results is a half wave end fed with a quaterwave counterpoise. I use a Miracle Ducker as an ATU. Works good. I used it once on the second floor of my house taping the wire to the top of door ways on 20 meters. I was surprised how well it got out with 5 watts. 1200 miles with a S5 signal report. Everything winds up and fits in the computer bag I use to tote the station around.
 
RE: Portable QRP Antennas  
by KL7IPV on January 24, 2007 Mail this to a friend!
Hamsticks and mini sticks work for me. A mini stick downside on a dipole adapter and a full size stick upside. When a signal is heard, rotate the vertical dipole to horizontal to use as a single element beam.
http://members.aol.com/sirdrakejr/backpackportable and
http://members.aol.com:/sirdrakejr/backpackdipole

The only real problem is trying to get out with a QRP 703 when the sunspots are at minimum. But I keep trying. It is STILL fun!
Frank
KL7IPV

 
RE: Portable QRP Antennas  
by KC5CQD on January 24, 2007 Mail this to a friend!
"Come to Towanda, PA where there seems to be an archery range in most people's backyard here in the borough. ;-)"



That guy was speaking of bows in CALIFORNIA.....where everything is illegal. You know...California....where the majority of the honest people pay the penalties for the transgressions of the minority of dishonest people.

In America.....the OTHER 49 states.....firing a bow isn't so much of a problem.

California is run by tree-hugging queers. That doesn't mean that the entire state is that way. In fact, I've met more "good ole boys" here in CA than I ever met in LA and VA but .....

In CA, the majority of people with money are tree-huggers and hence the state is as f*cked up as it is.

You people that can shoot bows in your back yards can pity us Californians. hihi!!
 
RE: Portable QRP Antennas  
by DG3YCC on January 25, 2007 Mail this to a friend!
My portable outfit: 10 meters of wire, endfed with a 1:9 Balun (more an un-un) and a good choke. No counterpoise. Mostly I mount the wire in an angle of abt. 45 degrees. Either from the hotel room down into the hotel's garden (fed point in the room) or up from the ground to my 8 meter high telescope fibre mast (fed point on the ground). With this outfit I worked Japan, Brasil, the US east coast etc. in 2006 from germany. Power was 20 watts from my FT 897, LDG AT 897 tuner matches the end fed wire from 10 to 40 meters. Wire, self made balun and choke added to 15 USD.

73 de Chris
 
Portable QRP Antennas  
by WA8MEA on January 25, 2007 Mail this to a friend!
Reminder: A Buddi-pole is NOT a true dipole. A trap dipole, a shortened dipole are just a couple of names "The Handbook" has used in the past for this style of antenna. Also, almost identical results can be achieved at a lesser price using Hamsticks and a dipole mount.

NOTHING beats a FULL SIZE antenna. Whether it's a loop, a dipole or a beam. Traps are proven to give you signal LOSS. (Buddi-poles, Hamsticks and the like use inductors...or coils (traps) for their design.)

Tuners can also be a tricky subject. Some use a T match, others an L match. Some use baluns while others don't. This has an effect on your loading and losses. Also, if your wire is just random and not a multiple of the frequencies you wish to work, you will also have problems.

73, Bill- WA8MEA
http://HamRadioFun.com
 
Portable QRP Antennas  
by WA8MEA on January 25, 2007 Mail this to a friend!
Somebody said:

"Fan Dipole".

Good one! But one of the most frustrating problems with fan dipoles is that once you've adjusted the SWR of one, the others are affected.

Our portable fan dipole is the easiest way to adjust the length of each radial of a fan dipole:

http://hamradiofun.com/yo-yo-vee-model4-6.htm

73, Bill - WA8MEA
 
Portable QRP Antennas  
by WA8MEA on January 25, 2007 Mail this to a friend!
As far as the HFPack.com Shoot-out results, they are from five years ago! Some of the newer antennas couldn't be included because they weren't even developed yet!

Also, Bud of Buddi-pole fame is HIGHLY active with the HF Pack team. Let's say he's involved in "management"....for lack of a better term. This MIGHT lead to certain results being skewed towards certain antennae. (Again...I used the word MIGHT!)

Please consider ALL reviews when looking to buy a portable antenna.

Again, consider the many FULL SIZE portable wire antennas that are on the market. Some are MUCH lighter than Hamsticks, Buddi-poles and the like if you are a back-packer.

73, Bill - WA8MEA
http://HamRadioFun.com
 
Portable QRP Antennas  
by KG9HV on January 25, 2007 Mail this to a friend!
I've been running QRP portable for the past ten years
and have tried many different antenna configurations.
Last year I used a 20M hamstick dipole on a 15' mast
and it worked, but not all that great. I've done the
wire in the trees and that worked also but alot of
work and not very convenient. It limited my operating position. I tried a vertical with ground
radials and that didn't do very well. This year I
have purchased a Jackite 28' telescoping pole and
will use it to support my 50' end fed Zepp made out
of twin lead. Figure I will run the wire up the pole
and the rest of the radiator will come down at an
angle as a sloper using string to support the end.
I also may use it to support an inverted V center
fed dipole. I'm sure this setup will deliver good
performance without putting a good part of my RF
into the ground. It will only take a few minutes
to set up and I can spend my time on the air instead
of cussing at a tree like an escaped mental patient.
When I'm done and ready to move on, a few twists of
the fiberglass sections will make this antenna drop
to the ground faster than a prom dress.
73
John KG9HV
 
RE: Portable QRP Antennas  
by W4LGH on January 25, 2007 Mail this to a friend!
~"Par Electronics EndFedz dipoles and a spiderbeam 40' telescoping mast. With this you can put up a REAL full sized VERTICAL dipole with the feedpoint at the bottom. Combine this with a hilltop campsite and you will be a very happy OM."~

I have a Par Endfedz for 20 meters and it is a NICE antenna, but they don't make one for 40meters anymore. They also used to market a mutli-band for QRP, but that seems to have gone by the by. So I don't know whats going on there. I would love to have one for 40M! Its as easy to setup as my random wire/tuner arrangement. Hang one end to a limb and start transmitting.

Anyone have any info on Par? What they are doing etc??

73 de W4LGH - Alan
http://www.w4lgh.com




 
RE: Portable QRP Antennas  
by GM0KMA on January 25, 2007 Mail this to a friend!
ummmm ... any kite users here?
Glenn
GMzeroKMA
 
RE: Portable QRP Antennas  
by N6ORB on January 25, 2007 Mail this to a friend!
>I have a Par Endfedz for 20 meters and it is a NICE antenna, but they don't make one for 40meters anymore.

Huh? The UPS guy should be delivering my 40 meter Endfedz today or tomorrow. At least Dale told me he shipped it on Monday.

N6ORB
 
RE: Portable QRP Antennas  
by W4LGH on January 25, 2007 Mail this to a friend!
~"Huh? The UPS guy should be delivering my 40 meter Endfedz today or tomorrow. At least Dale told me he shipped it on Monday. N6ORB"~

Interesting...I was told they didn't make it anymore...will have to do some looking into that! Guess thats what I get for taking someones word for it.

73 Alan
 
RE: Portable QRP Antennas  
by W4LGH on January 25, 2007 Mail this to a friend!
Just went to their site and it says nothing about any endfedz below 20meters....
Special Order?




 
RE: Portable QRP Antennas  
by N6ORB on January 25, 2007 Mail this to a friend!
You're right, it doesn't show on their website. But here's the secret code for buying the 40 meter version:
"I want to buy an EF-40 for $57 plus shipping."

I'm sure this incantation will work for you as well as it worked for me.

David Piersall
N6ORB
 
RE: Portable QRP Antennas  
by W4LGH on January 25, 2007 Mail this to a friend!
hahahahaha...Yea, CASH rules! You want it & you got the cash, somebody will do it for you!

Almost like the "GOLDEN RULE"...He who has all the GOLD RULES!!

Who was it that said Money couldn't buy everything?
Musta been that really Smart guy called MURPHY!
 
Portable QRP Antennas  
by W8KQE on January 25, 2007 Mail this to a friend!
I see the PAR 'End-Fedz' mentioned several times. I concur. I have 3, and they are excellent, compact and portable QRP antennas that 'get out'. And it is so easy to throw one up a tree branch and operate as a sloper.
 
RE: Portable QRP Antennas  
by KE6VG on January 25, 2007 Mail this to a friend!
Yep, I received my EF-40 back in November. The old qrp version I think is the the one that is discontinued. The new version is 65.5' and handles 200 watts. It has a small black matching box and 18 gauge black wire. Nicely built stealthy unit.

If you want to build the KW version you can do it with some coper 1/4 tubing to make the coil and a hunk or RG-8 or similar coax for the capacitor.

I have a couple of those 32' windsock poles, that the mast company sells, that I use to support it as an L.

I am going to try next to add another 65' of wire to the end of the PAR and turn it into a half-square. The matching box is a 5000 ohm matching unit roughly the same impediance that would be used in the half-square.

With the two windsock poles it would make a great 40 meter low radiation directional antenna especially for QRP DX work. Very portable with a little gain.
 
Portable QRP Antennas  
by M5TAW on January 25, 2007 Mail this to a friend!
End fed wires such as the zepp, or PAR are well suited to portable operation - as is the MFJ 16010 end fed wire tuner. I use mine with approx 1/2 wave length of insulated wire taped to a 10m fishing pole. For use on 30/40/80 I run the antenna up the pole and horizontally out from the top. I can tune most bands on most lenghts of wire - it's not fussy. I've had success with resonant dipoles too, made with thin insulated wire and fed with RG58. Both solutions are relatively cheap and easy to carry.
 
RE: Portable QRP Antennas  
by KQ6XA on January 25, 2007 Mail this to a friend!
> Bill WA8MEA wrote:
>
> As far as the HFPack.com Shoot-out results,
> they are from five years ago! Some of the
> newer antennas couldn't be included because
> they weren't even developed yet!
>
> Also, Bud of Buddi-pole fame is HIGHLY active
> with the HF Pack team. Let's say he's involved
> in "management"....for lack of a better term.
> This MIGHT lead to certain results being
> skewed towards certain antennae.
> (Again...I used the word MIGHT!)

Dear Bill WA8MEA,

Your snide suggestion that there might be "skewed results" by any person present at the HFpack Antenna Shootouts, is rather insulting to the all the operators who participated and witnessed the events.

They are the most highly documented and widely witnessed portable antenna shootouts in the world. In addition to the hundreds of hams who witnessed HFpack antenna shootouts over the years, there were independent volunteer dedicated witnesses at each shootout who did nothing but observe and verify that all measurements and procedures were proper.

If you can point to another reputable HF portable antenna comparison event, with accurate measurements, and many hams witnessed it, please let me know, because that is big news, and I will certainly put a link to it on HFPACK.COM

In the mean time, Bill, you should be aware that your put-downs of others and their products or the volunteers who test them as a service to the ham community, does not increase your own product's standing.

If you indeed think you have a better HF pedestrian or portable antenna, you are welcome to enter it at the next HFpack shootout and witness the measurements yourself.

73---Bonnie VR2/KQ6XA
Webmaster HFPACK.COM

/
 
RE: Portable QRP Antennas  
by KC8VWM on January 25, 2007 Mail this to a friend!
Again, consider the many FULL SIZE portable wire antennas that are on the market. Some are MUCH lighter than Hamsticks, Buddi-poles and the like if you are a back-packer.

73, Bill - WA8MEA
http://HamRadioFun.com

------------

Bill you have a great Yo Yo wire antenna design and I often tell other people about it. Especially the FT 817 crowd. It's very lightweight, inexpensive, portable, quick to deploy and it's performance rivals most other portable antenna designs in my opinion.

However, us hams already know it's performance really speaks for itself without any other competitive marketing talk required.

However, I have to admit that Bonnie does have a valid point too. I understand HFPack have very specific guidelines and rules pertaining to antenna manufactures involvement in these "independent" antenna testing methods used.

My constructive solution?

Why not put your own Yo Yo antenna's to the test at the HFPack shootout?

No, Seriously Bill,

I feel it would be a great way to effectively market your product to the "portable antenna" crowd.

As a businessman myself, I feel it's just good marketing.

Well I don't mean to get in the middle here but I hope you guys patch things up and maybe Bonnie, you will gain another antenna manufacturer to be featured at the next antenna shootout and Bill, you will hopefully gain a few more customers as the end result.

Everyone would most likely win. Including us consumers here sitting on the sidelines scanning HFpack.com looking for the latest and greatest portable antenna system for our FT 817's. Really.

My Best,

73 de Charles - KC8VWM
 
RE: Portable QRP Antennas  
by WA8MEA on January 26, 2007 Mail this to a friend!
A post from Bonnie:

Dear Bill WA8MEA,

Your snide suggestion that there might be "skewed results" by any person present at the HFpack Antenna Shootouts, is rather insulting to the all the operators who participated and witnessed the events.

They are the most highly documented and widely witnessed portable antenna shootouts in the world. In addition to the hundreds of hams who witnessed HFpack antenna shootouts over the years, there were independent volunteer dedicated witnesses at each shootout who did nothing but observe and verify that all measurements and procedures were proper.

If you can point to another reputable HF portable antenna comparison event, with accurate measurements, and many hams witnessed it, please let me know, because that is big news, and I will certainly put a link to it on HFPACK.COM

In the mean time, Bill, you should be aware that your put-downs of others and their products or the volunteers who test them as a service to the ham community, does not increase your own product's standing.

If you indeed think you have a better HF pedestrian or portable antenna, you are welcome to enter it at the next HFpack shootout and witness the measurements yourself.

73---Bonnie VR2/KQ6XA
Webmaster HFPACK.COM
-------------------------------------
A response from Bill:

Just the other day, I was commenting on how people read things into the printed word that actually are NOT printed. I do believe I even made a very fair attempt at trying NOT to be rude or "snide" as you state.... by reiterating the word: M I G H T .

snide Pronunciation (snd)
adj. snid*er, snid*est
Derogatory in a malicious, superior way.

(The word "MIGHT" removed ALL malice and the sentence wording itself was not derogatory.)

Again, if for ANY OTHER REASON, the results should NOT be the final word in ANY portable antenna purchase simply because the comparison is are from:

2002! Five year ago!

For that reason alone, one should check out the bevy of other antennae on the market....along with those reviews....and not rely solely on one test done from a half decade ago....

Sorry Bonnie. You didn't convert me on this one.

But best wishes anyway....

73, Bill - WA8MEA
http://HamRadioFun.com
 
RE: Portable QRP Antennas  
by WA8MEA on January 26, 2007 Mail this to a friend!
Once again we are on this topic of challenging another company's product, and the belief that somehow it "reduces" the credibility of the company that points out the other company's flaws.

How do you explain all of the negative campaign ads?

Because they work!

How do you explain the Coke-Pepsi TV commercial feuds?

The commercials work!

Just the other day, I saw one of the cleverest ads regarding H&R Block's version of tax software. It was a direct slam against "Turbo-Tax". The guy is getting audited after using "Turbo-Tax". The wife "snidely" says to the husband; "Who's going to defend you at your audit? This little box the "Turbo-Tax" came in?"

The jest of the message was to show that H&R had actual personnel that would PERSONALLY come to your defense in the event of a tax audit. Turbo tax doesn't. (Yet. That might change after that ad!)

Clever, funny, to-the-point & in-your-face advertising.

73, Bill - WA8MEA
http://HamRadioFun.com
 
RE: Portable QRP Antennas  
by KQ6XA on January 26, 2007 Mail this to a friend!
Dear Bill,

My previous invitation to you is rescinded.

73---Bonnie VR2/KQ6XA
 
RE: Portable QRP Antennas  
by WA8MEA on January 26, 2007 Mail this to a friend!
Dear Bill,

My previous invitation to you is rescinded.

73---Bonnie VR2/KQ6XA
-------------------------------------
To which Bill replies:

I really had no plans on taking you up on the offer anyway. And here's the reason:

A dipole...is a dipole...is a dipole...is a dipole.

There is nothing "special" about the performance of our portable Yo-Yo antennas. They operate just like any dipole should. Because it is what it is: A DIPOLE.

What we market is the PORTABILITY factor and the CONVENIENCE when adjusting the antenna to its proper length.

HOWEVER, if one tries to claim a shortened, or "trap" dipole (Such as a Buddi-pole or a Hamstick dipole...) will outperform a full size dipole...even a portable full size dipole....I have no other recourse than to contact Mr. Kurt Sterba of WorldRadio fame...who will gladly state that ANY such claim is 100% BUNK. (And 99.99% of antenna hobbyists/experts/columnists will agree. Including yours truly.)

Cheerio and have a good weekend.

73, Bill - WA8MEA
http://HamRadioFun.com
 
RE: Portable QRP Antennas  
by KQ6XA on January 26, 2007 Mail this to a friend!
Bill,

Don't be too sure of yourself.

You don't show any measurements to support your claims.

Take special note of the HFpack Antenna Shootout where they tested a "roll up dipole" very similar to yours. It was made of better materials than yours.

-3dB loss was measured for the wind up dipole antenna.

Half of the 5Watts of power was lost in the wind-up spools!

Have a nice day.

Bonnie
VR2/KQ6XA
 
RE: Portable QRP Antennas  
by WA8MEA on January 27, 2007 Mail this to a friend!
Don't be too sure of yourself.

You don't show any measurements to support your claims.

Take special note of the HFpack Antenna Shootout where they tested a "roll up dipole" very similar to yours. It was made of better materials than yours.

-3dB loss was measured for the wind up dipole antenna.

Half of the 5Watts of power was lost in the wind-up spools!

Have a nice day.

Bonnie
VR2/KQ6XA
********************************************
Again, this needs to be classified in the BUNK section of antenna theory. Measurements DO NOT need to be made because it is a DIPOLE. The standard for which all other antennas are judged!

Dipoles terminate at the END of the radial. Any remaining wire acts just like a wrap-around on a regular dipole. (Not knowing how the other dipole you mention is constructed; I am using MY dipole as the model....)

I went to the HFPack website. The antenna you describe is not even close to what we have, and certainly not of better materials. (Mainly because it is made of entirely DIFFERENT materials.)

I will offer this apology: I retract my statement about "The Shoot-out" skewing results in favor of Bud. I stuck my foot in my mouth before investigating the website's ENTIRE results.

Bud consistently showed figures in the negative dB range, thus proving that a short antenna will NOT be as effective as a full size.

73, Bill - WA8MEA
 
RE: Portable QRP Antennas  
by WA8MEA on January 27, 2007 Mail this to a friend!
One last comment before I move on:

If Bonnie's statement was correct, that the remaining wire of a portable dipole antenna produces LOSS, there HAS to be a scientific reason for it!

So I will assume that she must mean a coil has been created at the end of the antenna, and therefore an INDUCTOR is causing the dipole to "malfunction"...and therefore generating this so-called "loss". (An OFTEN misconceived "urban legend"....)

Now if this were true, the inductor would not allow the antenna to load (without a tuner, mind you...) at the resonant LENGHTHS of 40, 30, 20, 17, 15....etc. They would attempt to load at non-resonant lengths. For example, at 14.060 Megs....the portable dipole would try and load at 17 feet (figure pulled out of thin air purely for example's sake....) for each radial; instead of 16.64 feet (each radial, give or take a few inches....) for the actual resonant frequency length.

Our antennas operate at the 468/frequency in Megahertz lengths. I operate a Yo-Yo-Vee every day of the week. It was the ONLY antenna that survived not just one....BUT THREE ice storms this winter! ALL of my other wire antennas have come crashing to the ground.

I invite you to hear a Yo-Yo-Vee in operation. I am a regular on the 40 meter Century Club Net, checking in at 10 watts PEP on my Yaesu FT-107M.

For further info about the Century Club, visit:

http://www.3905ccn.com/

73, Bill - WA8MEA
http://HamRadioFun.com
 
RE: Portable QRP Antennas  
by WA8MEA on January 27, 2007 Mail this to a friend!
the portable dipole would try and load at 17 feet (figure pulled out of thin air purely for example's sake....) for each radial;
********************************************
Let's make that 12 feet. (Better example.) 17 feet is too close to 16.64 feet....

;-)

Bill
 
RE: Portable QRP Antennas  
by WA5ZNU on January 27, 2007 Mail this to a friend!
WA8MEA Wrote:
> ... A trap dipole, a shortened dipole are just a couple of names "The
> Handbook" has used in the past for this style of antenna. ... Traps are
> proven to give you signal LOSS.... (Buddi-poles, Hamsticks and the like
> use inductors...or coils (traps) for their design.)

A trap dipole and a shortened dipole are different things. A trap is a parallel tuned circuit that is used to present a high impedance (effectively an open circuit) at a specific frequency, to effectively
*shorten* (not lengthen), an antenna element by making it appear to end at that frequency. I think you will find information about this in the 2004 Handbook, on page 20.7.

Inductors alone (coils) are used to effectively lengthen an element, again seeing page 20.7 of the 2040 Handbook. While the efficiency is related to the amount of shortening and beyond a certain minimum
length the Q of the coil, of which the controlling factor is the ohmic losses. Most of the radiation takes place before the coil, because the high current section is what radiates, and that's close to the
feedpoint; after the coil, the current drops off rapidly and the rest of the "tail" has the effect of capacitive end loading to reduce the amount of coil needed to match (and reduce coil losses).

So, for a rough idea for efficiency for shortened elements, look for more element length before the coil, and then big coils with good wire, and possibly a top or end hat to reduce the amount of coil needed.

You might want to go re-read these sections and get acquainted with the design of trapped elements and shortened elements.

Leigh/WA5ZNU
 
RE: Portable QRP Antennas  
by WA8MEA on January 27, 2007 Mail this to a friend!
Leigh stated:

(And reduce coil losses).
*******************************
OK. The operative word is: "REDUCE". It does not say ELIMINATE.

BUT...they still exhibit LOSS....compared to FULL SIZE antennae. So in essence, you've just confirmed what I've said all along.

My reference was WAY before yours: copyright 1974. They use shortened and trap interchangeably. I agree, it's not quite the same. And I'm glad to see it updated. But for lay-people who are not into antenna theory, the object lesson is the same:

A SHORT (trap included) antenna is NOT AS EFFICIENT as a full size antenna of the same type, under the same elements of nature.

I.e. A full size beam vs. a trap beam. A full size dipole vs. a shortened or coiled dipole. A full size vertical vs. a trap vertical.

I will hand out as a prize, a NEW Sangean 505 receiver, our 40 meter Peanut Whistle Two QRP transmitter and Yo-Yo-Vee portable dipole antenna to ANYBODY who can prove otherwise.

Sincerely;

Bill - WA8MEA
http://HamRadioFun.com
 
RE: Portable QRP Antennas  
by WA8MEA on January 27, 2007 Mail this to a friend!
Bonnie stated:

-3dB loss was measured for the wind up dipole antenna.

------------------------------------
After re-reading this, you got me wondering. I'll bet it was the portable version with the reels at the TOP...and not at the end of the radials. This particular unit is constructed very well. But it's "bass-ackwards"....

In their case, you DO have inductance and a malfunction since you have created a coil at the apex of the antenna.

But when the reels are placed at the base, it's nothing more that a "dead end".

73, Bill - WA8MEA
http://HamRadioFun.com
 
RE: Portable QRP Antennas  
by WA5ZNU on January 27, 2007 Mail this to a friend!
You're absolutely right -- a shortened dipole is not as efficient as a full-length dipole. I'll go out in the garage and get my 1966 handbook when it stops raining (hi hi). But again, look at the illustration on page 20.44 (Section on HF Mobile Antennas) showing "Relative current distribution of base loaded antenna vs. loaded antenna." It's the same issue, but it's described in this chapter instead.

The center-loaded illustration is like the Buddipole, the PAC-12, and other such shortened antennas that did well in the HFPack shootout -- they all have a good section of element under the coil. You can see from the illustration that the current is high there, and so that section radiates a lot. Above the coil it tapers off until it's 0 at the end of the antenna (that makes sense -- where would the current go at the end of the wire). That end is a voltage node, and so the voltage is high there. That low-current/high-voltage end is one reason that even full-sized dipoles can droop the ends and not suffer in performance, and why they tell you to make sure nobody can come into contact with the ends, because of the high voltage there.

In fact, you can consider the drooped ends to be a capacitative top-hat or end loading, again a view that is consistent with allowing the ends to droop and not worry about whether they radiate or not. So you can consider a drooping dipole to be a shortened, end-loaded dipole. The end loading is more efficient than the center-loaded coil version, because there are is no coil to have ohmic losses, but you can, in fact, measure the ohmic losses in the coil and figure out what ratio that R is related to the radiation resistance of the antenna (which will be lowered from the 72 ohms of a full dipole), and that ratio is the efficiency.

Another point: an inverted Vee is an extreme case of a drooping dipole. The center has the highest current and it's up high so it radiates. The next segment just below the center is a little lower, and it radiates, just not as much because the current is lower, but it's also lower; unfortunately, it's also not horizontal and so you get a mix of radiation patterns. Eventually you get to the end of the wire and there's no radiation. So this is why the dipole with a long flattop section does the classic dipole pattern but the inverted vee is closer to the round vertical pattern, because of the mix of polarizations and orientations relative to the reflective (or more likely lossy) ground plane below.

So, you can see that even a dipole or an inverted vee, both just ~1/2 wavelength center-fed wires, can have loading effects that change pattern and efficiency.

But now back to the shortened dipole with the coil in the middle of each element. Again, the segment from the feedline to the coil radiates the most, and the part after the coil radiates the least (and eve increasingly so towards the ends). So, you can compare the radiation you get from the whole antenna vs. the radiation you get from a full-length dipole by comparing the ratio of the radiation resistance and the coil losses to get the efficiency. Additionally, because the current up to the coil is higher, using lower-loss conductors there helps to reduce losses (and incidentally if it is big and round it helps a little with the bandwidth over just using wire).

OK, enough with the theory...the practical tests and the modelling from antenna programs that take into account the current at every point show that antennas such as the Buddipole design (with its big conductors at the center, arms out to low-loss coils, and then many feet of telescoping end whips (which radiate some but also help reduce the amount of coil required to match and thus reduce coil losses) score within 1dB of a full-length dipole.

The big advantage a full-length dipole has with its reduced Q is the bandwidth. You can get great coverage across the band, feed with low loss coax and use a tuner in the shack to keep teh rig happy or use a tube's PI matching section, and you'll have pretty good efficiency with minimal components and not have to get up on the roof to change taps. But if you're portable, it's trivial to change taps and sometimes trivial to put up a 66' or 33' wire, and the efficiency is close enough not to notice.

Anybody up for a similar analysis of trapped antennas should probably just go read the handbook or the antenna book, but it's a similar process: follow the current, the voltage, and the impedance, and see where the losses, what the bandwidth constraints are, and what the presented SWR (impedance match) is to the feedline, to figure out what the tradeoffs that would lead someone to put up a trapped 80/40 dipole, for example.
 
RE: Portable QRP Antennas  
by WA8MEA on January 27, 2007 Mail this to a friend!
Leigh:

Let's throw another varibale into the mix: ELEMENT THICKNESS.

I use a 20 meter Inverted Vee constructed with #6 copper ground wire!

It covers the ENTIRE 20 meter band at less than 1.5 to 1.


73, Bill
 
RE: Portable QRP Antennas  
by WA8MEA on January 27, 2007 Mail this to a friend!
I just tried an interesting experiment outside before we get the real arctic air in a few hours. I took one of my Peanut Whistle coils....about three feet of wire wound on a 3/8 inch form.

I alligator clipped that to each END of each radial on my 75 meter dipole. It put me on a frequency of 3.910 Megs.

The next phase of the experiment: I took that inductor off, and placed three feet of wire hanging from the end. (The same amount of wire on the coil....) Tossed my frequency WAY down below the CW portion. Hi.

The coil and its form are about 1 1/2 inches long. I cut a piece of wire 1 1/2 inches long and alligator clipped that to the dipole...each end.

Guess where the frequency landed up?

You guessed it! 3.910 Megs.

73, Bill - WA8MEA
 
RE: Portable QRP Antennas  
by WA8MEA on January 27, 2007 Mail this to a friend!
Leigh states:

But if you're portable, it's trivial to change taps and sometimes trivial to put up a 66' or 33' wire, and the efficiency is close enough not to notice.
--------------------------------------------
Bill states:

Ahhhhhh. But to a hiker/backpacker....an antenna like the Buddi-pole that weighs a couple of pounds and is somewhat lengthy might be a detriment. Now an antenna like ours, which can fit in your coat pocket and doesn't even move the bathroom scale, might be better suited for those considering weight control when hiking/camping/backpacking....

73, Bill - WA8MEA
 
RE: Portable QRP Antennas  
by WA8MEA on January 27, 2007 Mail this to a friend!
Leigh says:

Anybody up for a similar analysis of trapped antennas should probably just go read the handbook or the antenna book, but it's a similar process: follow the current, the voltage, and the impedance, and see where the losses, what the bandwidth constraints are, and what the presented SWR (impedance match) is to the feedline, to figure out what the tradeoffs that would lead someone to put up a trapped 80/40 dipole, for example.
-------------------------------------------
Bill rambles:

I KNOW this is about QRP antennas. But what if somebody wants to go QRO while camping, backpacking or Field Day?

You are going to BLOW the inductor with one of those coiled antennae.

I've run 600 watts through our antenna. (Not sure how high it will go. I don't have an amp that powerful....)

But again....just another example of the MANY benefits of having a FULL SIZE WIRE ANTENNA....in portable form.

73, Bill - WA8MEA
 
RE: Portable QRP Antennas  
by KA4KOE on January 28, 2007 Mail this to a friend!
I use a reel style dipole, with about 55' of small guage teflon insulated wire on each reel. The reels are not at the feed point. It has a jury-rigged feed point. Suffice it to say, I feed the aerial with 300 ohm Wireman open window twinlead. The tuna in my manpack loads this baby up well on ALL bands 80m and up that my manpack will transmit on.

I feed with twinlead to minimize losses when operating on multiple bands.

I typically hang the antenna in inverted vee fashion. The entire antenna will fit in a zip lock bag, not including feedline, and weighs a pound at most.

I regularly check into my state's 75m traffic nets no problem and with respectible signals when operating portable. 20 watts output goes a long way.

Philip
KA4KOE

 
Portable QRP Antennas  
by AB7JK on January 28, 2007 Mail this to a friend!
A half wave vertical wire up in a tree tuned with a random wire tuner (MFJ 16010), along with an artificial ground (MFJ 931), tuning a counterpoise wire. Ten feet of coax between the transceiver and the tuner which was on a first floor window ledge next to the artificial ground.

Performance probably equalling or surpassing that of Par End Fedz on 20 meters. With such a setup I worked Japan, Australia, New Zealand and 35 other countries with 700 mw CW from Utah during the last sunspot low, 1996. TX was a Ramsey 20 meter transmitter, RX was a Sangean ATS 803A. AB7JK
 
RE: Portable QRP Antennas  
by N9AOP on January 29, 2007 Mail this to a friend!
I camp a lot and use an FT897D with an outbacker outreach antenna. I know that this is not as cheap as a wire in a tree but it will survive a beating and keep working. I have made contacts around the world using this setup and 5 watts.
 
RE: Portable QRP Antennas  
by KA5UOS on February 1, 2007 Mail this to a friend!
You guys are kidding, aren't you? You actually have to buy an antenna for portable QRP use? Someone actually sells them..for money? Really?

Wow!

K5UOS

PS..the original article was so simple. Too simple, maybe. I would think that would be the way to go. The complex math required must throw some people. But then again, look at the nice people you can buy antennas from.
 
RE: Portable QRP Antennas  
by WA8MEA on February 1, 2007 Mail this to a friend!
KA5UOS wrote, with sarcasm dripping from his trembling lips....

You guys are kidding, aren't you? You actually have to buy an antenna for portable QRP use? Someone actually sells them for money? Really?

Wow!
-----------------------------
Yep. It's a new business concept! It's called:

C O N V E N I E N C E

As In CONVENIENCE STORES?

That's actually how I got started. In 1989, I was ticked at all of the projects the magazines were publishing, and how complicated they were. Plus, you had to order via mail order from several different sources. (Some of which required a minimum $20 order.)

So for the price of a couple of stamps, paper and copy costs, I started advertising "ham plans" that required a dozen parts or less, all available at your local Radio Shack! (But they aren't available there any longer, I'm afraid.)

So I started getting mail back from these folks. They would ask if I would build it for them, since they were disabled, or were in a nursing home and not allowed to use a soldering iron. I had a lawyer customer tell me he was just too busy to build a QRP transmitter, and politely asked if I would build it for him.

And so DWM Communications was born. A nitch for the homebrewer...who couldn't/didn't/wouldn't homebrew his/her own.

I was just telling the wife a couple of nights ago, about the packet uproar in the early 90's about W5YI offering to renew licenses for hams, at $4 a pop. I could not BELIEVE the number of hams who called him a fraud, a scam artist, etc. since a person could renew thesmelves. But Fred was offering CONVENIENCE! I've used his service. Between a real job, this little part-time ham business, going to college full-time and raising five sons, it was just dam easier for Fred to do it!

Yep. Good old American capitalism. Don't ya just love it???

Contest time! (I love springing these on folks when nobody's looking.)

What is the radial length of the coaxial shield side of a half-wave dipole resonant on 7.175 MHz.

(Decimals instead of actual inches are allowed in your answer.)

First e-mail (address below) with the CORRECT answer gets a FREE Peanut Whistle Two QRP transmitter! (And they are fully assembled!) And a 40 meter crystal to boot! A $29.95 value!

73, Bill - WA8MEA
tinytenna@hotmail.com
http://HamRadioFun.com
 
RE: Portable QRP Antennas  
by WA8MEA on February 2, 2007 Mail this to a friend!
We have a winner!
-------------------------------
Rounded to the nearest tenth of an inch. 32', 7 3/8" if you prefer fractions.

73,
John, KJ6HZ
--------------------------------
Or 32.61 feet is another way of looking at it....

Congrats John! Your little transmitter will be on its way next week!

73, Bill- WA8MEA
http://HamRadioFun.com
 
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