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KX2/3 w/tuner owners: what antenna do you use?


#42

One antenna that is gaining popularity here in Austria is the Trekking Pole Antenna. Basically, it is just a BNC to banana plug adapter:

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…with a 7.5m length of wire attached to each terminal. Red goes over your trekking poles and black goes on the ground underneath. It tunes up 40m and above. If you want 80m, use 13.5m for each element; maybe a bit more in winter to get the tune right. Like many antennas, it may not seem like anything special, but it works; so I’m told. Personally I use an OCFD with my KX3.
de OE6FEG / M0FEU
Matt


#43

I typically use a 59’ long end fed sloper that is up about 25’ on a pole at the far end, with a small 9:1 QRP UnUn, 36" of RG-174 and a counterpoise wire laying on the ground that is about 25’ long. Sometimes I run the counterpoise wire out in the opposite direction - sometimes I run it out under the antenna. Seems to work about the same either way. It is 26 gauge wire - light and compact. Tunes 80-10 meters with the KX3 auto-tuner and gets respectable signal reports on all bands. Does not perform as well as my linked 40-30-20 half wave inverted V, but is easier to setup, allows faster band changes, and covers more bands. Jody - K3JZD


#44

Hi Joe,

I saw somebody else mention a speaker wire antenna. I used the concept from the 22nd Edition of the ARRL Antenna book and made mine cut resonate for 20m suing 22 gauge speaker wire. I make YouTube videos of my SOTA activations and I’ve been testing this unit out on my 817 for the last 5 summits with excellent results. My KX2 actually arrives tomorrow, but back to the antenna… I purposefully made a resonant antenna for 20m since that is the most versatile band while activating in my experience. I have worked from CA to FL, NJ and all across the US. I set it up as an inverted V type configuration and instead of the “NorCal Doublett” style I use just regular old speaker wire and cut a total length to include about 18-20’ above ground then I used 486/freq to start my legs. That purposefully gave me some room to wiggle since this calls for an “electricians knot” at the split to prevent it from opening up further causing issues. I then trimmed the antenna down and added insulators on the ends made of zip ties that have holes in them cut to account for threading the end of the wire and string to tie off the ends with whatever terrain I have. Again, go check out my YouTube channel for more on it’s performance but with 5 watts its doing a great job. I do orient it with the legs running NS so it’s broadside is EW facing and sometimes point the broadside a little NE/SW depending on where I’m trying to reach. By next week I should have the special section of the video I recorded on Monday’s activation edited to give you a visual and if you need any other info please let me know and I’d be happy to send my measurements and specific materials your way for consideration. My goal is ultra lightweight; hence why I promptly sold that Buddipole I bought too and have been shrinking my kit down as much as possible. My total pack weight with 3 liters of water, my entire radio kit, double lunch, snivel gear (cold weather stuff) and DJI Mavic drone with 3 batteries and controllers is sub 23 pounds! Hope this helps!

73 - KG6HQD - Jerry

PS - I do have on hand a LNR Trail Friendly 40/20/10 with 15 that’s tiny but the coax needed and antenna outweighs my entire 20m antenna described above but it worked pretty good and is small.


#45

Tell me, what is an EARC antenna.
73 de Geoff vk3sq


#46

Hi Geoff,
Plenty of info on the Web, this is one example;

73, Warren vk3byd


#47

So far so good - BUT according to antenna experts, the permeability 10 of the iron powder material #2 is far from sufficient.
To function as a broadband impedance transformer, the permeability of the UnUn would need to be in the range of about 125-2000, which requires the use of a ferrite material (e.g. mix #61, #43 or #77).


#48

I have been using the SOTABeams Bandspringer end-fed random wire and the 10m telescopic pole. The kx2 does fine tuning it without an unun. The kx2 can be a little picky on placement of the counterpoise on 20m, but it is not all hard to get to or below 2:1 across the band. I have on the to-do list to make a 64:1 unun and make a set of half wave end-fed wires to try, but I am not there yet.

I have built a linked dipole and like the performance at home. What I have realized is that, here in the southeast United States, the summits are not favorable for setting up a dipole mostly because of trees and other obstructions. My last summit, I could barely get the Bandskipper up vertically through the trees and shrubs. A dipole would have been utterly impossible.


#49

Thanks Warren. Appears to be a fancy name for an end fed long wire with a unun.

73 de Geoff vk3sq


#50

I am a relatively new ham radio operator - got my license in 2015. I don’t do much operating from home but I love doing SOTA.

I have a KX3 and have been using a 20m resonant dipole in an inverted vee. I use a telescopic mast about 20 feet high to elevate the feed point. I feed it with 25 feet of RG-316 (it looks silvery gold). The mast is guyed with 3 guy wires. I use SSB since I’m still working on learning CW. This setup has worked great for me. Lots of contacts and a few summit to summits as well. I use a Lipo 4S with a diode soldered between two sets of Anderson Power Poles to drop the fully charged pack down to less than 16 volts. The KX3 will shut off if fed with >16Volts. Once the voltage drops to about 15 volts as shown by the KX3, I can remove the diode. All this to make sure I can Tx on the full 15 watts. By the way the lipo pack is 1400 mA and I have yet to need any more on an activation.

The dipole can be difficult to erect on some summits. So I’m currently looking into an option that can feed the antenna from one end. Random wire, resonant half wave end fed, or vertical are the ones I’m looking into as a second option.

Thanks for all the posts on this subject - useful info.

Paul,
VA6TTX


#51

Paul.
I have played with it some and found for some reason I still pack my dipoles.
I have multiple wire lengths if you want to try them.

Malen
VE6VID


#52

Malen,

With our KX3 and KX2’s I think there is a broader selection of antennas available to us due to the awesome antenna tuner in these rigs. I see many people throwing up random wires directly connected to the rig, tune up and go. I also get the feeling that the performance loss compared to the dipole is minimal if you do it right - I mean you are high up on a summit after all. Slowly over time I will be investigating more options.

I am curious to try a 58 foot wire and a 13 ft counterpoise…should tune up no problem on the KX2/3.

Paul


#53

Since I started this topic back in January, I’ve done a number of activations and tried a variety of antennas before settling on more or less what I started with: a 41’ EF wire radiator, a 9:1unun which is also a winder for the wire, and 25’ of RG174 coax into the KX2. No counterpoise. This tunes down to 60m with good SWR. I’d been using a 16’ fishing pole for support, but I’m experimenting with using embroidery thread and a little weight to get the end of the wire up in a tree. One less thing to carry.

Other things I tried:

  1. Banana to BNC adapter to a wire and a counterpoise. This restricted operating position (doesn’t work well in a bothy bag for instance) and didn’t seem to get out any better than the above.
  2. Longer radiator (60’) with the same setup: allows 80m but not very well (spots were always very low s/r and signal reports bad). Not worth the extra hassle of 20’ more wire.
  3. Various counterpoises of various lengths and orientations with the above setup. These didn’t seem to affect s/n on spots appreciably.
  4. Linked 40-30-20 dipole. In a clear area this takes me 3x as long to set up. Practically, it was nearly impossible to deploy on a heavily wooded summit (I tried) and took much longer.

Most of my warm-weather activations will likely be done via trail running, so speed/ease of setup is paramount. To that end, I’ve also begun using my ATS radio (i.e. predecessor of the MTR radios) for the weight and size reduction. That demands a different antenna entirely, but that is another topic/thread!


#54

I use the linked dipole, EFHW, and any type of vertical be it a SuperAntenna, Buddistcik or Fishing Pole version.

I also have the Chameleon Antennas in different types. My last SOTA was using the Chameleon HYbrid as a NVIS antenna using 4 watts on SSB.

The KX antenna tuner seems to work great as well with a long wire and a radial hanging off the back with a bnc to binding post adapter for the minimalist using #26 silky wire. I challenge anyone to try any wire thinner without a mess of trying to unravel it all
john ve3ips

rememebr VE3 SOTA is activate now


#55

Been using a linked dipole must of the time or a doublet with the KX2/atu.
On a busy summit I used the dipole as an OFCD type using the 40m section at one end and 17m section on the other side.

I have got a two random wires I want to use on my next activation think they are either between 42 and 52ft long.

73
Graeme


#56

Hi Joe,

I use the PAR trail friendly mountain-topper antenna that covers 20-30-40. I used to use the SOTAbeams 30’ fiberglass mast with it - and sometimes still do - but lately tend to toss a line over a nearby tree branch, so the antenna far end is usually no more than 15-20’ off the ground at the high point. I’ve found that a really short coax connection between the matchbox end and the KX3 has a higher than desirable SWR, but when I use 25’ of RG-174u I am fine. There’s probably some interaction between the coax and antenna causing this, but the bottom line is as the ads say: “It just works.” Plus, in many AZs, it has been very useful to have a 25’ feedline.

For 20 and 40, I usually don’t need to use the tuner unless the setup is really compromised, for example, in some AZs, I’ve just strung the antenna atop the high brush growth and gotten out. If I removed the shorting SMA male connector from the “center” insulator for 30M operation, I probably wouldn’t need the tuner there either; but often I am lazy ;-), or the insulator is not convenient to access, so I just use the tuner when I switch to 30M. Band changes with this antenna take seconds. If my tosses are decent, setup or take-down can take as little as 15 minutes.

To keep it simple, I’ve avoided any antennas that require more than one tie-off. Most of my activations have occurred during the winter months, so as you’ve noted, I want to make things as easy and fast as possible when the temps are low!

I will add a backup antenna along the lines of what N7RR has described…

73 Paula k9ir


#57

May I respectfully suggest that embroidery thread might be a little thin & thus cut into tree limbs. (Yes, I’m a tree hugger. :heart_eyes:) If you feel it grabbing maybe something like Zing-It, which is made for this very purpose. It’s very lightweight & slippery- so easier to pull through trees & not get tangled. I put a permanent loop in the end with a Brummel splice (McDonald Brummel) to hook weight on.


#58

I am very happy with the KX2 tuner, it tunes everything. Avoid some lenghts. Tunes a lot better than my IC7300.I tested that a few weeks ago. When I have a pole with me I prefer my 10 mtr hyendfed vertical. No tuner needed for 10/20/40 mtr and it tunes easy on 30 mtr if you are CW-man. Small footprint on busy places, and there is always some support, where I go anyway. I am qrv in 7-8 minutes. I never use it, but I have also a spare endfed with jumpers, so I can use other bands as well. The transformer is ok for 80-10 mtr.
Did >700 summits and 18 countries with the hyendfed !!!
73 de Hans PA3FYG


#59

Using here an EFHW for 20 and 40 with a HB9BCB coupler and 1 m of Coax. It was my starter device and still is and runs well mostly, except for Jürg, HB9BIN, hi. (This will take me some time to resolve since that way particular!)

Vy 73 de Markus, HB9DIZ


#60

I got to playing with wire antennas today while hanging on a summit while a few others were activating. The 58 / 13 wire at about 7.5 to 8’ tuned 40-10 1.1-1 while 80 metres tuned slightly higher. I figure I would see if I could get any S2S’s and managed 1 from the Black Hills SD (Thanks Donald). 10 metres was sort of open, I heard the human beacon on 28.425 mHz, but as per normal he won’t answer me. So it seems to work for me.

Malen
VE6VID


#61

Gene, where did you buy the 49:1? Or find the plans? Thx! Scott kw4jm