Dave Richards AA7EE

May 24, 2010

Telescopic Fiberglass Masts – A Must for Every Ham

Well, I’ve been settled into my new place for a while now.  I’ve done a little bit of amateur radio (though not much) and embarked on a new project which, although not a ham radio project, is still radio related.  More on that in a subsequent post.

My new digs are in a 100 year-old house with an easy-going landlord.  The landlord part is key, as I have already erected one antenna, and have plans for one or two more.  I’ve often noticed that a shake-up in my lifestyle will cause a change in the interests I pursue, and this move was no exception.  Even though I felt that ham radio was about to take second place to something else, I still wanted to put up some kind of antenna for the HF bands.  A quick scout around the internet led me to the website of The Mast Co (link opens in a new window) with a great selection of telescopic fiberglass poles. The 32 foot heavy duty model seemed ideal for mounting on my balcony and attaching some kind of vertical to  so a few mouse-clicks, a few days of waiting, and an hour fiddling around on the balcony led me to this:

This is the pole in it’s retracted position with the top cap in place. I strapped it to the balcony with large plastic ties that I got from Home Depot. You can see that I’ve used cut-up pieces of old bicycle inner tube to protect the paint finish on the pole from being chafed by the ties and to cushion the pole against the faucet.  This is a first floor balcony at about 11 feet above ground, so the top of the pole is about 43 feet above ground.  The top of the pole is a little higher than the sloping roof of the house and the house is at the top of a small hill (Oakland is quite hilly), which works out quite well.  Anything sitting at the top of the pole (like an antenna) will have a good view of the east bay.

This doesn’t really show you much, but here’s a shot taken from ground level of the pole fully extended:

I ran a length of 26 gauge magnet wire from my window to the top of the pole and then down again to the other end of the balcony – a total length of about 75 feet. As soon as the wire gets through the window into my room it connects to a 4:1 balun after which about 15 feet of RG8 goes to the Z11 tuner and then the radio. I draped about 40 feet of wire around the perimeter of the balcony as a counterpoise and what do you know – it tunes up on all HF bands 80 thru 10.

Of course, just because an antenna tunes up doesn’t mean that it radiates well. To this date I haven’t done extensive testing, only having had 4 or 5 QSO’s. The furthest was on 40M (CW of course) with AD5WI in Pea Ridge, AR – a distance of 1547 miles. He gave my 5 watts a 599, so I might be on to something with this antenna.

The great thing about the telescopic pole is that it is very much a multi-purpose item.   According to Henry K4TMC, the proprietor of The Mast Co, this pole can support a lightweight HF dipole fed by RG8X (lightweight meaning made out of fairly light gauge wire with no traps).  You can also support a small beam if you attach it part-way down the mast.  This is a great all-purpose experimental antenna mast. To extend the pole, you just pull out the sections and twist them a little so that they stay extended – they hold together by friction.  It retracts just as easily. My mast has been up continuously for 3 weeks now with no problems. The poles are made to hold windsocks, and this one seems to handle wind quite well, flexing when it gets gusty, but staying up.

There are so many uses I can think of for a lightweight extending pole like this. Because it’s lightweight (5lbs for the heavy duty 32 foot pole), it doesn’t take a whole lot to support it. This particular one will most likely stay on my balcony and be used to support a variety of different antennas.  The next plan is to mount a vertical antenna for the MURS band at the top and use it to test the coverage of a couple of MURS handhelds that will be arriving here in a few days.  My friend lives a mile away and isn’t licensed, so we decided to play around with MURS as a way of keeping in touch.

If you have any questions about this mast, please don’t hesitate to ask.  I’m quite enamored with it. Henry mentions that this particular pole isn’t being made any more so when he runs out of his current stock, that’s it. Think what you could do with a lightweight and very portable 32 foot telescoping mast………

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13 Comments »

  1. Nice to see you are setup…ship shape! I am hoping we will be able to QSP soon.

    73 Brad WF7T
    Nashville, TN

    Comment by Brad WF7T — May 28, 2010 @ 8:32 pm | Reply

  2. Looks like a great idea to get a dipole or a vertical up quickly.
    Ka7niq

    Comment by roofcleaningtampa — February 12, 2011 @ 10:06 pm | Reply

  3. It is Chris. I’m currently using it to support an inverted vee for 40M which is getting out well.

    Comment by AA7EE — February 13, 2011 @ 3:41 am | Reply

  4. No, it doesn’t have to be that lightweight – at least not for the 40M inverted vee. I used thin insulated stranded wire – about 22 gauge. Mine has white plastic insulation, which seems to be better than darker colors for not standing out too much when viewed against the sky. Instead of using insulators at the antenna ends, they are tied to nylon fishing line (40lB test) – no need for insulators, which saves on weight. I run the RG8X coax down the mast and secure it with velcro straps. This antenna has been up about 6 weeks through some pretty strong winds and hasn’t come down, so it looks like the mast is supporting the weight of the coax and antenna wire fine. For a longer antenna, you might have to use a thinner gauge.

    Comment by AA7EE — February 13, 2011 @ 3:16 pm | Reply

  5. I am weighing my options. I live in Tampa, not deed restrited, but on a very small lot. No trees to speak of, and little room or desire for guy wires. I may just get a trapped vertical, and hang it on a chain link fence ? I really need a self supporting structure to hang an inverted v from. I have been looking at heavy wall PVC Pipe, ever looked at that ?
    I wonder how high I could go with it, and have it truly be self supporting to support an inverted v ? Stealth is not a problem in my Tampa location, we are not deed restricted. They make heavy wall PVC sewer pipe in all kinds of large sizes.

    Comment by roofcleaningtampa — February 13, 2011 @ 3:29 pm | Reply

  6. Here is some preliminary stuff on telescoping PVC Pipe I found http://flexpvc.com/PVC-Telescoping-Pipe.shtml
    UV rays are supposed to be hard on PVC, but that can be solved easy enough if it turns out to be a real problem. Remember, they use PVC pipe in sewers in place of concrete in some areas. If you get the heavy wall stuff, it is really strong, unlike the flimsy stuff commonly seen. Do you remember any of the metal or aluminum self supporting masts sold for ham radio use ? They were simply large diameter pipes at the base, with progressively smaller sections added. The bottom sections went into concrete, and used a winch to pull the top sections up. I don’t recall how the top sections locked into place ? They required NO guy wires!
    Most were really expensive, but they did what they said. I have always wondered if it would be possible, or cost effective to duplicate them out of heavy wall, large diameter PVC Pipe ?

    Comment by roofcleaningtampa — February 13, 2011 @ 3:52 pm | Reply

  7. Interesting stuff Chris, and I have no experience with PVC pipe other than using about 15 feet to support a VHF antenna a couple of years ago.

    The problem with any kind of dipole fed with coax is that it is a single band antenna. You could add extra sets of dipole wires at the top for multiband operation, or you could feed the dipole with balanced line and tune it with an ATU. There is a variation of the G5RV developed by ZS6BKW that looks interesting also.

    Good luck and let me know how you fare with the PVC piping if you decide to go that way. I do seem to remember an article in QST in the last few years about a 160M vertical made from PVC pipe. It was wound on the pipe helical style.

    Comment by AA7EE — February 13, 2011 @ 4:01 pm | Reply

  8. The article I was thinking of is in the June 2009 issue of QST Chris. It’s called “The No Excuses 160 Meter Vertical. I’m not sure if it’s supposed to be available on this site, but I found it here:

    http://www.hamuniverse.com/k6mm160metervertical.html

    He guys this antenna, so it may not be off too much interest to you though. I know you said that you don’t want to use guys. Sounds like you’re looking to make a kind of self-supporting mini-tower with PVC pipe. Let me know how it goes!

    Comment by AA7EE — February 13, 2011 @ 4:21 pm | Reply

  9. LOL, I read that article you provided, got to LOVE that Ham! I used to live in Seattle, and had a 110 foot tree at my home. I hung a 20 meter vertical dipole in it fed with open wire feeders. It was great on 20 through 10 meters, especially for DX. In that article, the guy has a huge tree next to the PVC Vertical. IF I had some trees to use, my problems would be over. But trees in the part of Tampa I live in are almost non existent, or they are very small. Or, they belong to my neighbors who hate me, because my kids have car stereo’s with bass. I was just looking at prices of large diameter, heavy wall PVC or CPVC pipe. It is about 4 dollars a foot for 3′ diameter schedule 80.

    Comment by roofcleaningtampa — February 13, 2011 @ 4:32 pm | Reply

  10. A 100 foot tree? I’m drooling at the thought. I bet you miss that tree!

    Comment by AA7EE — February 13, 2011 @ 4:37 pm | Reply

  11. I have had a LOT of success with trees! I once bought a surplus spool of wire, it was over 5000 feet. I spent a weekend pulling it through trees at a previous location here outside Tampa. It made a huge loop from 30 to 50 feet in height. It broke all the “rules” as the wire was supported by laying on tree limbs! Never measured where it was resonant, LOL
    I fed it with 450 ohm wire, about 140 feet of it. It loaded easily on all bands, and was insane on some bands. On 17 meters, from Tampa I was 20 over 9 into northern europe, yet into southern europe I never got above S9.
    I guess it had wicked gain lobes ? But if you happened to be in one of the monster loops favored directions, watch out! It got out real well on 75 and 40 meters too, but not too good on 40 meter local. It seemed to favor 40 meter DX over local. Actually, the monster loop broke, but stayed up. It was just a random length wire, but still worked well. It was just more touchy to tune. I am a big believer in what my long departed Elmers taught me, get as much wire up as high as possible, and open wire feed it.

    Comment by roofcleaningtampa — February 13, 2011 @ 4:48 pm | Reply

  12. Hey Dave – good to find this article about your Telescopic Fiberglass Mast. Mine arrived this morning – a mere 27ft tall and light as a feather. I’ve no deck to strap it against so I’ll have to rig up something on the side of the house, to get a little more height. I’ll probably need to put 3 guy ropes about 14ft up. It gets pretty windy here when the southerlies arrive off the Winter Antarctic ice cap. It will be a good test for it.

    I’m also doing away with porcelain egg insulators and will try strips of PVC white or grey pipe to reduce weight and wind resistance. The heaviest items will be the braided copper dipole wire and the 1:1 balun that sits right at the top of the inverted V pole.

    If this combo works it will be a practical way to get some antenna height without towers and handy trees etc.

    My first version, not as high, was a piece of pipe strapped to a J support that once held a TV antenna, bolted to the side of the house. Alas it had an encounter with a courier truck which snagged one of the inverted V legs and dragged the whole shebang to the ground. The event sounded like an earthquake and out of the corner of my eye I saw my studio mixer (caught in the feedline coax) rocketing against the wall of the shack. Man, that was a baaaad day!

    Dave, how’re you doing? Are you well and contented? What are you up to these days.

    73 – John – ZL1AZS

    Comment by John S — February 26, 2013 @ 1:04 am | Reply


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