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Author Topic: What is your ideal PORTABLE QRPp antenna?  (Read 52786 times)
N2QGV
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Posts: 16




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« Reply #30 on: December 16, 2010, 03:20:57 AM »

Wow, hamsticks in a backpack. I am waiting to hear about that.
Anyway, as I said before, the Par 10/20/40 is the most versitile antenna I can take with me. I have even laid it across the top of a 6' wood privacy fence and worked stations. If I got to a place that could not even allow for that, then my "bad" and no operating. Or, I would just go to an area that offered a sky hook. If I knew before hand the Par was a No....... then I wouldl have to choose from my Buddipole Deluxe, Superantenna MP-1, or Miracle Whip. My favorite is still the Par, can't be beat for quick and stealth deployment.

73
Art
Have fun...............
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KATEKEBO
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Posts: 117




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« Reply #31 on: December 16, 2010, 11:51:10 AM »

Here is what I use:
- three MFJ mobile whips (similar to Hamsticks) for 40, 20 and 15 m.
- one Buddistic "deluxe" 9 ft telescopic whip for 10m
- Super Antennas MP1 tripod
- four 1/4-wave resonant counterpoises (for 40, 20, 15 and 10m)
- one set of 8 radials (about 8' long each)

The MFJ "sticks" and the telescopic whip fit nicely on the MP1 tripod.  I use the 1/4-wave counterpoises when I operate the antenna elevated (on a wooden deck) or on concrete / paved surface.  I use the radials when the antenna sits to reasonably conductive surface (for example wet grass).

The nice thing about this setup is that it fits into a 4'-long, 4"-diameter cardboard tube for easy transportation, and it does not require a tuner.  Once the antennas are initially tuned, it's a "plug-and-play" setup that does not require field tuning.

I have made QSO's as far as 4500 miles with these antennas using 5W on SSB.

I also have the PAR ENDZ 40/20/10, which is great if you have something to hang it from.  It easily outperforms the "sticks", but the downside is that you need some trees to hang it from.

I also have a Miracle Whip which is OK for transmitting on 10m, and for listening on all bands.  I use a random wire extension (about 12' long) for 20m (never tried it on other bands) with the Miracle Whip transformer and a 1/4-wave counterpoise, and it seems to be comparable to the MFJ "stick".

KD8KQH

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KV6O
Member

Posts: 90




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« Reply #32 on: December 19, 2010, 07:33:33 PM »

I have traveled all over using my pac-12 antenna - packs small, lightweight - good for use in the field.  But the best portable antenna I have used is an end fed wire fed with an Emtech ZM-2. I can match just about anything with that tuner!  I operated from Puerto Rico with a IC-703, the ZM-2 and about 90 feet of wire thrown into the trees from my third floor balcony and worked all over Europe on 80M - and got great signal reports!

Once while in Framingham (outside of Boston) I was on the 7th or 8th floor of a hotel with the same setup - outside my window and about 25 feet away was the top of a large tree.  I tied one of the hotel shampoo bottles around the end of the wire (and tied the other end to the desk!) and threw the bottle into the tree, where it dragged the wire out about 25 feet, then down about 60 feet. From ground level if you knew where to look you could see the shampoo bottle hanging there :-)

This setup allowed me to work EU stations, as well as stateside with a pretty good signal. 

The Pac-12 works when there are no supports, and is pretty efficient on the higher bands, but nothing beat the end fed wire. Small, cheap, lightweight.

Steve
KV6O

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WB6BYU
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Posts: 13341




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« Reply #33 on: December 20, 2010, 12:21:17 PM »

 For those of you who use a portable antenna other than a wire - what is the maximum linear dimension
that you would consider practical to carry?  I'm looking at designing a tripod + vertical whip type of
antenna and am wondering what limits I should put on the lengths of the individual pieces.  The last
overseas trip I took I found that my sectional flag pole was slightly too long for my luggage.  At
the moment I'm inclined to aim for 18" or so - small enough that it could go in a carry-on bag.

Thanks!
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WD6GLA
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Posts: 75




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« Reply #34 on: December 21, 2010, 12:08:12 AM »

A collapsable 20 foot fiberglass fishing pole  ( maybe  20 bucks )  and either a dipole fed with 300 ohm twinlead  , or a half wave end fed wire with a homebrew matching unit .  Light , cheap , portable , and it works ...... and very well too. 

The rub is the support to hold up the pole .    Now here you have to be creative ... a tripod is heavy to lug around . You said no trees or rocks and that makes makes it more difficult .  A metal support stake takes a hammer to bang it in the ground .  Its heavy .  If you have a vehicle you can use it to support the pole .  On foot  you dont want to lug all that weight .  So each case is different , play it by ear as to where you will be setting up to operate ........... but those two types of antennas are the best for portable work   ,  hands down .   

Bob
N7BDY
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K2QPN
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Posts: 70




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« Reply #35 on: December 31, 2010, 08:10:55 AM »

I have been a fan of verticals since the 1960's. I had been using a Super Antenna MP-1 vertical for years for portable QRP and QRO operating. I had replaced the 6 foot whip with a 12 foot whip. I added a sturdier tripod from Blue Star antennas. Always worked well.

While operating QRP portable his summer I needed to make a quickie antenna. I went to RadioShack and bought 50 feet of speaker wire. I built a NorCal doublet - cheap, easy, quick. Fortunately, my PFR-3 has a built in tuner. 

While doing an ham radio demo for some Boy Scouts, I had the opportunity to compare the MP-1 vs the doublet. The doublet won hands down. I compared them on 40, 20 and 15 meters and the doublet's signals were a good S unit stronger. I was impressed. I bought a 20 foot crappie pole to support the doublet center in an inverted V configuration. I am going to do another comparison but right now a Norcal doublet is my new portable of choice.

73, Bob K2QPN
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WB6BYU
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Posts: 13341




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« Reply #36 on: December 31, 2010, 09:14:50 AM »

Thanks, Bob.  That's the type of comparison that is useful, though of course it depends on the
stations you are trying to work, the soil type, etc.  It isn't so much that  any one antenna is
always better than another (though that may be true sometimes), but rather that certain
conditions will favor one type of antenna over another, and we need to understand the tradeoffs
in our particular circumstances and make a good choice.

We had an emergency communications event a few years ago with units from two adjacent counties
set up in the same parking lot.  One group had 100 watts to a 5-BTV, the other had 5 watts to a
thin wire dipole fed with RG-174.  It was a "valuable learning experience" when both groups checked
into the state-wide 75m net with the same signal strength:  the group with the vertical brought their
radio over and plugged it into the dipole just to see how much difference it made.  Needless to say,
that group now uses dipoles for NVIS operation.  The situation would have been very different if
they had been set up on a salt marsh trying to work DX.
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ZENKI
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Posts: 960




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« Reply #37 on: January 01, 2011, 04:16:43 AM »

Dont forget the pseudo Brewster angle,  makes or breaks vertical antennas not the type of antenna.

I operate my K2 from all over the place.  My favorite antennas are these.

Low band interstate short skip work a low dipole. You get 6 db ground reflective gain  roughly. I generally use a 80 meter doublet fed with open wire feedline.(light tv ribbon)

For DX work I like the verticals.  I like using the end fed halfwave for  20 meters. I do use it with 2 gull wing radials. It works well when the ground conductivity is average to good. When its poor I use a 9 meter fiberglass pole  fed with a 4:1 unun as a  all band vertical with as many radials as possible. Near saltwater its a killer antenna.

The best 14 to 30 mhz dx antenna that I have ever used is the HF Skeleton  slot antenna. When this antenna is strung up into a tree say at 35 feet its a killer antenna from 7 to 30, best from 14 to 30 mhz.  I use a spiderpole to erect it and feed it will ladder line for all bands.

The best low band portable/semi portable antenna that I have used for low band DXíng  is the single wire double magnetic slot. It does not require a lot of height and will  keep with with a 4 square. The DX pileups on a magnetic on 7mhz is incredible and it requires no radials.

I am mainly a DXér, i dont put up antennas to talk down the road even when operating portable or QRP. I regularly get accused of not being QRP or a being BS artist by stations running home stations with the typical low G5RV stapled to the house gutter. These are the hams who dont really understand how effective  and important a low take off angle is. All these antennas that I have mention all achieve a very low takeoff angle  when installed at modest heights that can be found at many portable QRP locations.

Needles to say I dont mess with low dipoles, kite antennas or longwires. My first priority is always the takeoff angle then the efficiency  combining factors of ground loss or brewster takeoff angle.

 Try the antennas that I have mentioned and you will be impressed. If you  just want to talk to your friend in the next state a wet string will do on 40 meters. For this I carry a end fed wire thats fed with a 9:1  balun.


If I had to chose one location for portable operation it would be a island surrounded by sea water. Even a miracle whip works from a salt water location, however  the above antennas have given me a good feeling of being LOUD when portable.

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WB6BYU
Member

Posts: 13341




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« Reply #38 on: January 01, 2011, 09:17:00 AM »

Quote from: ZENKI

Needles to say I dont mess with low dipoles, kite antennas or longwires. My first priority is always the takeoff angle then the efficiency  combining factors of ground loss or brewster takeoff angle.



Exactly - you have to understand the advantages and limitations of the different antenna types and
how they apply to the communications you are trying to accomplish in your own particular situation.

But don't rule out long wires entirely - they can be quite effective when combined with the proper
topography.  I operated my Argonaut from some logging camps on the islands of southeast Alaska,
and my main antenna was a 130' wire zepp fed with 300 ohm twinlead (since those were the materials
available.)  The best setup I had was for Field Day one year when I hiked to the NW point of the local
salt water sound.  I tossed a rope over a cedar tree at the water's edge then, at low tide, I walked
out on the tide flats and tied off the end of the wire to an improvised support.  When the tide came back
in I had a sloping longwire over salt water pointing Stateside.  That was good enough to break pileups
on KG4 and KZ5 (back when they were DX prefixes.) 

My station was set up on a plank across a driftwood log, operating out of a garbage bag to keep the
rain off the equipment and with the antenna tuner under a plastic hard hat.  I was so busy operating
that I didn't notice the tide had come up to the back side of the log - I almost went Maritime Mobile!
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WB4TJH
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Posts: 192




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« Reply #39 on: January 22, 2011, 07:36:37 AM »

I like my Par Endz fed half wave qrp antenna for 40, 20, and ten meters. I also use a dipole fed with 300 ohm feedline and an MFJ qrp tuner with built in balun. Both are superb antennas systems.
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IZ4KBS
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Posts: 94




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« Reply #40 on: March 01, 2011, 02:02:32 PM »

A couple wires and a small tuner make more sense to me for backpacking.

I've just stumbled upon this interesting thread, so let me step-in. I agree with the two wires and tuner suggestion. I have tried all sorts of setups in the quest for the "perfect" /P antenna: resonant, non-resonant, tree-supported, kite-lifted, basically everything conceivable. Each solution has its pros and cons, of course. In the end I settled on the two-wire-and-tuner, for:

  • Full-size wires: in most practical /P situations they get detuned by the surroundings: think of an hotel room, a balcony, the wire casually hoisted into a convenient tree, etc, so you'll end up needing a tuner anyway. Plus, it's not always (almost never ?) easy to accommodate the 10 meters of wire needed by a full-size dipole, neither vertically (hotel), nor horizontally (crowded beach, hotel room/balcony, etc.).
  • Short whips: terribly inefficient if all you can feed them with is QRP(p). I don't like them.
  • Kites: great fun, but go figure about handiness Smiley .
  • Trees: rarely mother nature places a suitable one where I need it, if at all.
  • Hoisting weaponry: slingshots, guns, crossbows, you name them. All but safe, clumsy to carry/use, forget them (throw-bags are better, but they still need trees: BTW, tree branches and leaves are lossy, too).


I mean, all the above can be used in specific situations where it makes sense, but none of the above can be seen as an all-purpose /P solution, if that's what the OP is asking for. Hence the two wires, both of 25-28 feet in length: one is the radiator, the other one is the (single) counterpoise. The latter doesn't even need to be laid straight, and it can usually be supplemented by a convenient metallic structure nearby, or often by nothing at all if on 20m and up, where capacitive coupling, the body of the operator and all that can provide all the "ground" that is (reasonably) needed. The radiator can be set up more-or-less vertically with a lightweight fishing pole of suitable length, so that you don't need to rely on local supports, that may not be available. The radiator does not need to be vertical, nor straight, so it can be made to lean out of an hotel balcony/window, and that. Of course you need a tuner, which needs to be small and have a built-in SWR indicator, like the fine NorCal BLT (which can handle unbalanced antennas just as well), or an even smaller homebrew one (here's an inner view of my own 20-40m L-network, which is really tiny: http://www.strozzi.it/users/carlo/hamradio/misc/epsn4945.html).

Performance-wise, I do not know of any /P antenna which is not a compromise, and resonant wires are no exception: I believe that a low dipole, albeit resonant, isn't all that more efficient than my own two wires. EFHWAs are fine, and Dale's dipoles are the best ones I know of, but try and set them up half-decently out of a hotel balcony or on a crowded beach (unless it's the 6m version, of course). Plus, I have found that over rocky soil, such as atop high mountains, you do need some sort of counterpoise, be it one (or more) separate wire or a run of feedline providing the same function.

Caveat: I'm only concerned with /P setups. Going pedestrian it's a very different problem I have no experience with.

Just my 2-cent, hope it helps.
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N1JWW
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Posts: 1




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« Reply #41 on: March 02, 2011, 04:11:42 PM »

Par Electronics End Fedz here...  I have several of them..... 

N1JWW  Jeff
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NA7U
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Posts: 72


WWW

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« Reply #42 on: March 22, 2011, 11:40:01 AM »

The simplest pack antenna I ever made and was pleased with was one using a length of 300 ohm twinlead (like Radio Shack sells). You need enough to make a 20 meter dipole plus enough extra length to make a 1/2 wl transformer (can't remember the exact dimensions, but you can calculate it easy enough, be sure to take VF into account). It's all one piece of line. Put a couple of fishing swivels in the end and hoist it up. Works as a 20 M dipole (obviously) and on 40 meters it radiates on the whole line, horizontal and vertical. Light as a feather.
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WB6BYU
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Posts: 13341




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« Reply #43 on: March 22, 2011, 12:30:51 PM »

Quote from: NA7U
... and on 40 meters it radiates on the whole line, horizontal and vertical...


Can you explain this further?  Are you changing the feed system on 40m to make it
unbalanced to get the feedline to radiate?  Otherwise the currents will be equal
and opposite in the two wires of the twinlead and it won't radiate.

While this approach does give a good match to 50 ohms on 20m (half wave dipole fed
with 1/2 wave of 300 ohm twinlead) it won't match on 40.  The impedance at the
center of the dipole is probably around 15 -j1000 or so, and the impedance at the
transmitter end of the line would be about 6 - j100, with over 5dB of power lost in
the twinlead (even using an optimistic model.)
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K9JWV
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Posts: 5




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« Reply #44 on: April 09, 2011, 11:45:41 AM »

I do some hiking to activate Summits On The Air (SOTA) and have tried various portable antennas....the ONE that works the best for me and appears to be the most effective, yet simple to erect is this:

A 28' Jacktite collapsible mast with an End Fed Half Wave (EFHW) hanging from the top.  The tuner is a KI6J EFHW tuner ($27.00 in kit form) that will tune from 40 through 15 meters.  The counterpoise is about six feet of wire.  The length of the coax from the tuner to the rig (either an ATS-3B or ATS-4) is about six feet.

I've worked plenty of EU stations from the summits I've activated out here in s/w Utah.

Let's see....$27.00 for the tuner, couple of bucks for the coax and wire, $55 (or so) for the Jacktite - not a bad total cost for an efficient antenna that can be set up in minutes and doesn't need a tree!

Regards, Jim Rodenkirch, K9JWV
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