Field Report: Let’s build a super simple antenna on-site and activate this park!

Until 2016, I had never purchased a commercial field antenna; I built all the ones I had ever used.

These days, I take a number of commercial antennas to the field and use them in my real-time videos and I really enjoy deploying and using them. My buddy Eric (WD8RIF) reminded me, though, that I hadn’t actually used a homebrew antenna in ages. He was right!

You see, while I believe commercial field antennas can be incredibly durable and compact, it’s important to note that antennas are one of the easiest components of an amateur radio system to build yourself. They require only the most simple of tools and are very affordable. And the best part? They can perform as well as those that are available commercially.

I also get a great deal of pleasure out of building things.

A simple goal

I’ve mentioned in previous posts that I often set a little goal that runs in the back of my mind for each park or summit activation I make.

On Monday, June 14, 2021, I made a simple goal: buy my antenna wire en route to Lake James State Park, build the antenna on site, and complete a valid Parks On The Air (POTA) activation.

A very simple antenna

I also decided to employ my Xiegu X5105 since 1.) it’s one of the most affordable general coverage QRP transceivers I own and 2.) it has a built-in antenna tuner (ATU).

One of the cool things about having an ATU is that, if it has the matching range, you can allow it to do the “heavy lifting” in terms of matching impedance.

Although I’d never put the X5105 to the test, I suspected its internal ATU would have the matching range to forgo building a 4:1 or 9:1 transformer and simply pair it directly with a random wire.

All I would need was a 28.5 foot length of wire for a radiator, at least a 17 foot length for a counterpoise, and a BNC to binding post adapter.

The antenna would benefit from multiple 17′ counterpoises, but I really wanted to keep this setup dead simple to prove that anyone can build an effective field antenna with a very minimum amount of components.

Even though I have plenty of wire lying around the house to build this simple antenna, I wanted to pretend I had none to prove that any wire would work.

And to add just a wee bit more challenge, I also limited myself to shopping for antenna wire between my home and the park without making a serious detour from my route. That really limited my options because there isn’t much in terms of commercial areas between me and Lake James State Park.

The wire

As I left the QTH, I decided that the best spot to shop was a Walmart in Marion, NC. It would only be a four minute round-trip detour at most.  I had a hunch that Walmart would even have speaker wire which would be ideal for this application.

In my head, I imagined I would have at least three or four choices in speaker wire (various gauges and lengths), but turns out I had a difficult time finding some at Walmart. We live in such a Bluetooth world, I suppose there isn’t much demand for it these days. A store associate helped me find the only speaker wire they had which was basically a 100 foot roll of the “premium” stuff for $17 US.

While I would like to have paid a fraction of that, in the end it’s not a bad price because once you separate the two conductors, you have double the amount of wire: 200 feet.

Although the frugal guy in me cringed, I bit the bullet and purchased their speaker wire. To be clear, though, I could have found another source of wire in that Walmart, but I preferred speaker wire for this application. And $17 to (hopefully!) prove a point? That’s a deal! 🙂

Lake James State Park (K-2739)

Once I arrived on site, I found a picnic site I’d used before with some tall trees around it.

Here’s how I prepared the antenna:

First, I cut 28.5 feet of the speaker wire from the roll and split the paired wires so that I’d have two full 28.5 foot lengths.

Next, I stripped the ends of the wire and attached banana jacks I found in my junk drawer. Although these aren’t necessary as the binding post adapter can pair directly with the wire, I though it might make for a cleaner install. In the end, though, I wasn’t pleased with the connection to the radiator, so dispensed with one of the banana jacks on site, and later dispensed with the other one as well. The connection is actually stronger without the banana jacks.

I then deployed the 28.5 radiator with my arborist throw line, and laid the other 28.5 half on the ground (the ground of this antenna would pair with the black binding post, the radiator with the red post).  I only needed 17 feet of counterpoise, but once it couples with the ground, I don’t think any extra length makes a difference (although less than 17 feet likely would).

The antenna was essentially set up as a vertical random wire with one counterpoise.

I then plugged the BNC binding post adapter into the rig, hit the ATU button, and was on the air.

It’s that simple!

My new speaker wire antenna in all its glory.

Gear:

On The Air

I’ll admit: I was a bit nervous putting this antenna on the air. Although I felt the X5105 ATU *should* match this antenna, I had no idea if it actually would.

Fortunately? It did.

At this point, if you don’t want any spoilers, I suggest you watch my real-time, real-life, no-edit, no-ad, video of the entire activation (including buying and building the antenna!).

Click here to watch the video.

Otherwise, scroll for my activation summary…

I was very pleased that the X5105 found a match on the 40 meter band.

I started calling CQ in CW and validated my activation by logging 10 stations in 13 minutes.

Honestly: it doesn’t get much better than this.

I logged three more stations on 40 meters CW, then moved up to the 30 meter band where the X5105 easily found a match.

I worked one station on 30 meters before heading back down to the 40 meter band to do a little SSB. I logged three SSB stations in five minutes.

Mission accomplished!

In the end, I logged a total of 17 stations including a P2P with K4NYM.

Not bad at all for speaker wire!

After the activation, I tested the X5105 ATU by trying to find matches on other bands–I was able to find great matches from 60 meters to 6 meters. Most impressive!

X5105 battery

You might recall that I attempted to deplete my X5105 internal battery at my last (rather long) activation of Lake Norman State Park.  I wasn’t able to deplete the battery at that activation, but I finally did at this one.

All I can say is that I’m incredibly impressed with the X5105 internal battery.  This was my fourth activation from one initial charge on May 16.  The battery lasted for 20 minutes, taking me well beyond the 10 contacts needed to validate this park. I’ll now consider taking the X5105 on a multiple SOTA summit run!

Short Hike

Even thought the heat was intense and the humidity even more intense, I decided to take in a 2 mile hike post-activation. I snapped a few shots along the way.

This is the Christmas Fern which derives its name from a few characteristics: its resilience to early season snows maintaining a dark green color beyond Christmas, and because folks believe its leaves are shaped like Santa’s boots or even Santa on his sleigh.

Improvements

I’ll plan to add more counterpoises to the speaker wire antenna as I know this will only help efficiency.

In addition, I’ll plan to build even more antennas with this roll of speaker wire. If you have some suggestions, feel free to comment!

Thank you for reading this field report!

Cheers,

Thomas (K4SWL)


Do you enjoy QRPer.com?

Please consider supporting us via Patreon or our Coffee Fund!

Your support makes articles like this one possible. Thank you!

23 thoughts on “Field Report: Let’s build a super simple antenna on-site and activate this park!”

  1. Thomas,

    Other good sources of emergency antenna wire is your local hardware store. They should have a roll of basically speaker wire for use in repairing table lamp cords. They may have other sizes for home repairs/construction, depending if there is a nearby box store (Home Depot, Lowes, etc.). You should be able to buy it by the foot. Another good lightweight insulated wire is doorbell wire, usually 18 ga solid copper as a lightly twisted pair. I found that at a Lowes in a 100 ft spool for less than $25. Although heavier, 25 to 100 ft AC power extension cords and some alligator clip leads make great radials. Used ones are usually real cheap at yard/garage sales and thrift stores.

    1. Very sound advice!

      And, yes, my hardware store actually does have decent wire options. There was also a Lowes Hardware in the area–maybe a 20 minute detour–and occasionally you can pick up good deals from their scraps and returns.

      Thanks for sharing!

      Cheers,
      Thomas

  2. Thomas what is the name of the “All Band HF Transceiver” at the top of the page. It has a gray face . Nice looking rig. 73 John W3JJB

  3. Thomas,
    Why the 28.5 length. I assume it is to avoid a half wave or multiple thereof on all the bands? What about the 17 ft counterpoise? Is that a calculation or just through experimentation?

    Bill
    W8BC

    1. Exactly, Bill.

      I used 28.5 feet because that’s the length my buddy WD8RIF has used with his wire vertical (which has four 17′ counterpoises). There’s a list somewhere of non-resonant lengths that make for good random wires.

      I should think that the counterpoise length of 17′ is essentially a reliable minimum amount. If longer and lying on (coupled to) the ground, it really shouldn’t matter.

      Cheers,
      Thomas

  4. Thomas,
    I have been out of the radio loop since I got sick over a year ago. It totally obliterated my desire to do anything in the hobby besides read this and a few other blogs. I have a Yeasu 450D and was never really happy with it. I realized after spending some time with it that I really only had fun with QRP level activations and I didn’t know much about more portable options at the time (it was my first HF radio after getting my General ticket).

    I am really considering getting a Xiegu X5105 based off the reviews you have given while actually using the radio. I just have to start saving up! I would like to one day learn CW because it seems very interesting to me. I will have to look into a way to learn it that works for me of course and figure a way to practice at some point but first Ill need a radio.

    I have to tear down my set up anytime I want to use the radio due to where I live so a base station was not the answer to begin with, live and learn I guess lol.

    Anyway, thank you so much for your amazing writeups and keep doing what your doing!

    John
    KN4ESP

    1. Hi, John,

      You bring up a good point: the radio model can have a lot to do with your enjoyment of field radio.

      Being honest here, the FT-450 is one of my least favorite late model 100w transceivers. Much of this has to do with the design and ergonomics, but also the fact that it easily overloads in the presence of strong signals. It’s one of the worst Field Day radios I’ve ever used (I operated in 2 field day events where the club stations were all the 450).

      The X5105 is not a perfect radio, that’s for sure. But I like it nonetheless. It gets the job done, is completely self-contained, and works well in the field. Like the FT-450D, I wouldn’t try using it on Field day or in the CQWW contest, but for 98% of my operating? It’s great.

      I’m writing a full review of the radio for The Spectrum Monitor magazine. In that article, I’ll take a deep die into what I like and some of the cons. Overall, though, I recommend it. I think it hits the sweet spot of performance and utility and an incredibly affordable price.

      Cheers,
      Thomas
      K4SWL

    2. There are tuned single-band whip antennas, with BNC connectors, available from MFJ and probably other sources. I have gotten a 20 meter one and also a set of 8 loading and coils and one telescoping whip, all through ebay. The antenna will mount right on the radio, and with the built-in mic and speaker, you have an HF walkie-talkie.
      There is a youtube video of operation like this by OM0ET called
      “Great Walkie Talkie QRP contact! with XIEGU X5105 – YouTube”

  5. Right up my alley (well…again)!

    Some thoughts I had while watching:

    – You live in a great landscape there! When you drove down that road I expected you for a split-second to stop at Ike Godsey’s general store to get the wire (wrong state, wrong time, fictional store, I know). 🙂

    – Of course you know that, just acting like the wise guy here: If there’s a connector/adapter/transition you can avoid between output and antenna, avoid it. Banana plugs, particularly cheap screw-on types can be full of surprises, when sizeable currents are involved they can even become a bit hazardous . Now here’s something you don’t know yet:

    – I believe the FCC (or was it the FAA? AMA? BMW? PETA?) recently issued regulations re ham radio related YT videos: There is now a mandatory quota of 1 minute of Hazel per video in effect. Just kidding, but everything is even better with a dog (or cheese), right? She’s so cute and the lingering possibility that she suddenly relocates the antenna, the radio or the OP adds a subtle thrill ! 🙂

    Seriously, I think I really learned a few things by watching these videos, keep ’em coming!

    1. Ha ha!

      Your point about avoiding an unnecessary transition is well taken and you’re correct. I’ve already removed the other banana jack, in fact.

      I was recently sent a notice by the FCC stating that Hazel must be in 57% more of my videos to meet minimum requirements. 🙂 She loved going with me to parks and on hikes and just chilling by the radio waiting for a squirrel to appear. Sadly, though, her ear surgery is now scheduled for next week and she’ll be out of commish for 2 weeks or so and wearing “the cone of shame.” But in the long run, this procedure should really help her hearing and comfort. Maybe once she hears my CW properly, she’ll want to stuff her ears with cotton! 🙂

      Thanks for your comment, OM!

  6. Aw, sad to hear she needs surgery, crossing my fingers for her! I’m sure she’ll be fine with your CW though! 🙂

  7. Thanks Thomas.

    I made one today. It only took about 10 minutes and was extremely easy to do. I haven’t tested it with my G90 as it is already packed away for my NC trip.

    Since I don’t have an arborist throw line and bag I will deploy it as a sloper using my 21’ telescoping fishing pole. The only difference is I have to use a BNC to PL-259 as the G90 has a SO-239 connection. No big deal.

  8. Random wire suggested lengths are here

    https://udel.edu/~mm/ham/randomWire/

    the counterpoise is usually about 1/3 or 1/4 of the antenna, to improve things it would be a good idea picking a pair of FT140-43 (ok for 100W) and use them to wind a 9:1 unun and a guanella choke

    https://vk6ysf.com/unun_9-1_v2.htm

    https://vk6ysf.com/balun_choke_balun_hf_reisert.htm
    the two may then be hosted inside the same plastic box offering wire binding posts, coax connector and possibly a post to hang the box

    The UnUn will ease the ATU job and the choke will avoid using the coax as part of the antenna

    my 2 cents 🙂

  9. Good morning,

    Another fine complete report, I love it,
    After reading this one, I checked in my junk box, and I have found
    many speaker wire, and the double banana connector like the one you have. So sure will try it this fall, , Ir looks like it is a good performing antenna.

    But I have a 100$$ dollars question.

    I like very much when you put a small map with all that QSO you worked.

    What happened with ham radio in Canada ?

    When you work one it looks like it is very rare one!!

    Where are they ? Even for me, it is really difficult to work some Canadian station except during some contest. It seems to me that over the years, it is becoming harder to work some chaser
    in the POTA/WFFF/SOTA .

    My impression, is here in Canada this is really not un fun game for the vast majority of amateurs radio .

    What do you think about that ?

    Thank you again for all that very good, instructive articles.

    Keep on this very good complete works, I like that.

    Best 73, Mike VE2TH The QRP’er

  10. Having now soundly achieved the majority of my portable (park) contacts with a speaker wire antenna matching yours, I’d back to thank you for this post. I found my 100′ coil of 18 AWG speaker wire for just a couple bucks at a thrift store, plus a little more to keep a nice number of BNC/banana adapters on hand. It definitely takes a little wobbling of the counterpoise end to get resonance on 40m, but will casually tune 20/17/15/12/10 with my Z-817! The whole assembly coils up nicely, is adequately tangle-avoidant, and goes up promptly with a throw line or fiberglass pole. Absolutely must recommend for a portable HF operator to have one.

    1. I was just telling someone this weekend that the speaker wire antenna is one of my useful antennas. It’s so flexible and durable, too and easily covers 40-10 M with my KX2, KX3, X5105, X6100–or with the T1 to match. So glad it’s working out for you!

  11. I tried a 28.5 ft wire up a telescopic mast with a radial. It was a noisy day and getting late but got in a contact on 40.
    By the way, the 5105 doesn’t seem to have a backlight since I upgraded to 3.0 firmware. Am I doing something wrong? I can adjust contrast fine but the backlight settings don’t seem to do anything. Maybe it just failed.
    73 John N4HNO

Leave a Reply to Frank ON6UU Cancel reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.