Portable Antenna Masts
Almost all antennas need something to get them up in the air. Trees are commonly used for dipoles, wire verticals, slopers, Inverted Vee's and so forth. Towers, poles and roof tripods are often used for multi-element "beams" or verticals as well. Portable operation often raises the need for some kind of transportable mast as trees or other supports may not be available or convenient. Enter the fiberglass push-up pole or mast. I've used two such masts with good results. This page and the links discuss those.
2022-07-25 Until several days ago I have only used my 10 meter Spiderbeams mast with my drive-on mast stand shown below. But last week I wanted to use it in a park while I sat at a picnic table in the shade at POTA park k-4265 so the mast needed to be free standing out in the grass about 60 feet away and not near my car. Based on my experience with the shorter 20ft masts I knew what to do. I added a cross piece on the "foot" I've been parking on. But a issue was that this mast is ten feet longer and considerably heavier. Using three bricks on the stand as pictured I did manage to keep it upright while it was calm but as a breeze started picking up I knew it wouldn't take much to topple it.
My temporary solution is to rig up some guy ropes. Pictured above is the result. I say temporary because I'd like the guys and the way I "attached" them to the mast to be a bit more elegant. But they work. It would take quite a wind to bring it down. And best of all, I didn't spend any money on it - yet! I really do like collapsible masts and this one is a good addition to my kit. It's solid, easy to erect and with its 28" collapsed length is easy to transport. With it supporting my KM4ACK 40 meter EFHW, set up either as an inverted vee or sloper, I think I have an effective, reasonably portable antenna system.
2021-11-03 A few days ago I purchased a Spiderbeams 10 meter fiberglass pole/mast. I had not anticipated how large it would be! The collapsed length of about 28 inches made me think it would be more-or-less like the 20 ft fishing poles I already have. It weighs almost 5 lbs and its bottom section diameter is 2-1/4 inches! Thirty two feet (10m) is tall compared with my 20 ft poles!
So, how to hold it upright. Guy ropes would clearly work and would be easy to DIY. But winter is approaching and the ground will soon be frozen, so I need something that does NOT need to be put into the ground. A drive-on stand seemed like the best option to me which seemed verified by feedback I got on the POTA Facebook Group. Great, I've done that before as you can see in my previous posts. So off to our local home store to buy some PCV and a floor flange to essentially duplicate my previous drive-on stands. But... they didn't have any floor flanges for 3 inch PVC pipe! But the Facebook group came to my rescue again by suggesting a toilet flange. So the two pictures below show the result. It is a 2 ft piece of and of a retired book shelf with the toilet flange screwed upside down onto it with 1/4 lag screws and a 2 foot piece of 3 inch PVC cemented to the flange. It works. I had two QSOs this afternoon using my 40/30/20 link dipole.
2021-07-04 An improvement to my drive on mast mount was to put a cross piece on it so it can be used free standing. Turns out that is the primary way I use it now. I carry a couple bricks with me to give it more stability in windy conditions. It makes deploying a wire antenna such as an EFHW inverted vee or non resonant end fed really quick and easy and quick. I attach the inverted vee antenna by passing the wire through the loop formed by the bungee cord. The wire can slip easily through it. For tying off the end of a sloper I simply tie it to the loop in the bungee cord. Again, quick and easy.
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2020-11-03 OK, last(?) change to my drive-on winter antenna system. Until now I've only thought about the mast support on frozen ground or other ground that can't be happily penetrated by a stake or guy lines and tent pegs. But then I realized I haven't really thought about what to do in the same situation if there are not bushes or trees available or reasonably accessible. Since my portable wire antennas are made with light weight wire, #24 or smaller, The ends don't need very strong anchors. Short tent pegs or even flimsy shrubs work just fine. So, I thought, why not just have a couple small buckets filled with sand or cement, weighing maybe 3 or four pounds. Tie my bungee cords to those. As I kicked the idea around with my wife last evening she suggested gallon water jugs. Brilliant! Of course in very cold weather they might need to contain antifreeze or alcohol or something but the idea is great.
Today was a perfect weather day especially for Wisconsin. About 70 and sunny. Should have gone to a park but instead I set up my cold weather kit in my driveway and made 3 POTA contacts as a hunter in about 15 minutes plus one SKCC. Was running 5 watts SSB except for teh SKCC contact which was CW. Rig was Xiegu x5105 using internal mic. Antenna was a QRPGuys 40-10 EFHW inverted vee. Center support was a 20' carbon fiber fishing pole off Amazon held erect with my DIY drive-on support. Ends of the inverted vee were anchored with 1 gallon water jugs. And RG-8x coax entered my vehicle through a window topped by a 1" foam pipe tube from local home store. All worked well. Can set up even with frozen ground! May need jugs of antifreeze rather than water! Thanks to the activators who humored me!
2020-11-02 When I went out to Richard Bong State Recreation Area for a POTA activation this past Saturday, it took long enough to put up my mast that my hands were getting cold. And the temperature was around 40 degrees with a strong wind. That got me to thinking I need a quicker way to get the mast up. Why I didn't think about this before I don't know, but I rebuilt it using a larger floor mount pipe flange and 1-1/4" PVC for the stand pipe rather than the 1" one previously. Now I can just drop my push-up mast into the pipe and be done! Literally just seconds required once the car wheel is on the drive-on board. I haven't actually used it yet but I'm sure it is in improvement.
2020-10-30 I live in Wisconsin and winter is a force to be reckoned with. One issue is how to deploy a portable antenna mast when the ground is frozen. I learned last winter that you can't even extract a tent peg after a couple days of below zero temperatures! So guy lines, stakes driven in the ground, etc., may not be options.
It occurred to me a couple days ago that the drive-on mount could be one option. So I found a 1x6 oak board about two feet long and bought an 18 inch threaded piece of 3/4 PVC water pipe and a mating pipe flange. It only took a half hour or so to mount the flange and screw in the pipe. To mount my fiberglass or carbon fiber push-up fishing pole I simply strapped it to the pipe with several turns of 1/8 inch bungee cord held fast with a cord lock to hold the cord tight. I put one at the bottom and one at the top. That was last night when it was dark and cold.
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This morning, when it was cold and light, I backed the car out of the garage and drove the front wheel onto the 1x6. Then I tied my 20 ft push up Carbon Fiber Ultralight Telescopic Fishing Rod to it using two pieces of 1/8 bungee cord and a couple cord locks. Then I attached the tip of my QRPGuys 29ft end fed wire to it and pushed it up. I tossed the transformer/winder into the shrubs at the front of our house and laid out the 17' counterpoise. Then I ran a 25ft piece of RG-174 coax from the transformer through a nearby window to my Xiegu X5105 and fired it up. right away I heard N4MTE on 7.278 calling CQ POTA from K-4172 Jackson on Patoka Lake State Recreation Area, 348 miles away and answered him. To my surprise he came back immediately giving me a 55. He was 55 in here! I then went on to have one more contact on 40 meters and two others on 20 meters. All were sideband except with KB5QFU on 20m in Saginaw Texas, 840 miles south. I was happy with the antenna, the drive-on mount and my x5105!
2019-07-18 My son accuses me of buying something cheap only to later have to replace it. It is probably a valid accusation! And I may have done it yet again with a new "fishing pole" I got via UPS yesterday. It's a Goture 1 Piece Carp Fishing Pole, Carbon Fiber Ultralight Telescopic Fishing Rod that collapses down to 28 inches. It weighs ten ounces and extends to 24 ft. I got it off Amazon, of course.
When it came yesterday I was shocked how small it is, the bottom section just 3/4 inch in diameter! And the tip section is tiny! I was sure I had wasted my money. But as I looked at I noticed that it is actually pretty strong and decided if I left the tip section inside the next one down even the tip was strong and it only shortened the pole by about 20 inches.
So this morning I set it up in the yard. My 29 ft end fed non-resonant antenna uses very light weight wire so doesn't put much demand on the support. And the pole holds it up very well. The photo doesn't do a very good job of showing it but it bends far less than the Shakespear Wonderpole I've used previously. So I'm very pleased. It may well be my goto portable mast from now on.
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2019-02-05 This morning while "working out" on the treadmill I was watching a YouTube video of a ham going into the woods near his house, setting up and making a contact over 3000 miles away with just a couple watts. The thing that intrigued me was that he had so much trouble trying to put up his fiberglass push-up mast that he gave up. It appeared that like many others I've watched he was extending his mast on the ground, attaching the antenna connection and then trying to stand up the unwieldy thing!
I remember trying that when I first got my push-up mast and thinking, there has to be a better way! My "better way" was to come up with a way to stand the pole up collapsed or at least partially collapsed, and guy it in the vertical position. Then I attach the antenna, leaving its ends and the coax (if it is fed at the top of the mast) hanging down and then push up the mast section by section. Once fully extended I can attach the loose ends to surrounding trees or whatever.
To guy the partially pushed-up mast I came up with a collar that would fit somewhat loosely on the section above the guy point, sitting on top of that lower section. I found that if the collar was about three or four feet up and the three guy lines went out about four to six feet the mast is stable. One does need to extent enough top sections that the tip is above the guy point or you won't be able to extract it from the partially pushed-up mast.
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Using this approach I can have my mast up with antenna furled in just a few minutes by myself and avoid balancing it like a broom on your nose in the process!
Attaching a wire antenna to a fishing pole
2018-08-10 This afternoon I decided to try the 40/20 meter trap inverted vee with my 5.4 meter Bamboo Pattern 11 Section Telescoping Fishing Rod and see if I could make some contacts. As expected the FT817nd liked the low swr on both bands and put out full power on both 40 and 20. There were very few QSOs on either band but I did finally snag one 40 meter CW QSO with KC0M in Branson, MO, just under 400 miles away for a brief but solid QSO. He gave me a 579 and he was a strong 589 in here. The antenna set up easily using the shock cord arrangement described and shown below. I think it is a keeper. Sorry the picture at right isn't clearer but hopefully it shows how it all goes together. As it shows the pole coming in from the bottom left corner flexes quite a bit.
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2018-08-10 One issue I faced with both of my fiberglass fishing pole masts is how to attach an antenna to them. The Wonderpole came with an eyelet on the tip which worked fine for attaching my 32 ft wire. I simply formed a loop at the end of the wire, attached a small clip sort of like a safety pin and clipped the antenna on. As mentioned below, the 5.4 meter fishing pole did not have anything on its tip. So I bought a fishing pole eyelet and attached it. That worked well for the 32 ft. antenna.
But an inverted vee presents a different problem as you have to support the center. I describe my solution for the Wonderpole on my pages about both the 40/20 meter fan inverted vee and the 40/20 meter trap inverted vee using a piece of pc board and a grommet. But that won't work on the 5.4 meter pole as it is way to small near the tip.
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So, after thinking about it for a while I came up with the idea of using a short piece of shock cord and a cord lock. The photos show the result. Very simple. Just tie a knot in the shock cord near one end and pass the cord through the center insulator from the bottom. Then put the upper end of the shock cord through the eyelet on the fishing pole with the cord lock above it to keep the cord from pulling through. It is simple to make and to attach both of which I like.
Shakespeare TSP20 Six-Piece Wonderpole
2018-08-08 I've played with two portable masts. I have the most experience with a Shakespeare TSP20 Six-Piece Wonderpole fishing pole with the top element removed so the antenna center is 16 ft. 6 in. from the ground. It's pretty sturdy, easy to erect and fairly light weight at just over 1.3 lbs. My friend and I used two of them on the recent 2018 ARRL Field Day. One to hold the center of a 40/20 meter fan inverted vee and one to hold the center of a 40/20 meter trap inverted vee. Since then I've played in my back yard with a 35 ft. end fed wire antenna. It works well with all of them. If it has any down side it is its collapsed length of 45 inches. That is not an issue when driving to your site and it can even be lashed to a backpack for a walk-in site. But it is a bit unwieldy for that.
5.4 meter (17.7 ft) Bamboo Pattern 11 Section Telescoping Fishing Rod
2018-08-09 This afternoon just before a rain started I quickly put up my 5.4 meter mast from China and rigged a way to tie the center of my 40/20 meter inverted vee to it. I wanted to see if the foot or so shorter mast would have any appreciable impact on the SWR of the antenna. As nearly as I could determine using the mfj 259b antenna analyzer, which is what I've used for my other tests, there is no noticeable difference.
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Of course the antenna may be even more of an NVIS antenna with the center angle being a bit flatter and thus the ends approaching the ground quicker. Not sure how I might test that. The photos show the mast in my back yard with the antenna on it.
2018-08-08 Just this week after waiting for over a month, I received from China another fishing pole mast, a 5.4 meter Bamboo Pattern 11 Section Telescoping Fishing Rod. It measures just 22-1/2 inches when collapsed and stands about 15 feet when opened up with the top section removed. It weighs just slightly over a half pound. It clearly is not as robust as the Shakespeare one but seems to support my 35 ft wire antenna OK. This pole came without anything on the tip to connect the antenna to. So I got a Danielson Rot Tip Repair Kit at the local Dunham's Sports store and cemented it to the rod tip using an instant cure cyanoarcrylate cement from a local hobby store.
How to guy the mast
With most portable masts you are going to need some way to guy it to keep it upright. In some cases the antenna wires themselves can serve at least in part as guy wires. SOTAbeams has a video showing how to erect and guy their pole with the antenna. They use the two legs of an inverted vee, the feedline and a single guy wire which is a very good approach in some cases. It is worth watching as their "business" is gear for operators going to mountain summits to make contacts. They have a lot of experience, some in fairly challenging antenna situations.
I decided to fabricated collars for my fiberglass masts from scrap PVC pipe and fittings that seem to work. I've yet to really test the smaller one in the field but my collar arrangement worked on Field Day for the Shakespeare masts. The two masts and my fabricated collars with guy lines are shown below. The guy lines themselves are five to six feet long. The collar fits on top of the bottom section of the larger mast and the third one on the smaller one. Finding PVC pipes and fittings that just slip over the upper section of the mast and sit nicely on top of a lower segment is part of the fun!
I'm still experimenting with both masts at this stage but have had both supporting wire antennas which would work in the field. More to come. Probably the simplest approach would be to simply buy one of the Sotabeams masts. I just like playing around to see what I can rig up, thinking I'm saving money. In the end I'm probably spending more! :-)