Stacked Dipole for 11M

Stacked Perpendicular Dipoles for 11M

I'm fairly new to radio but I am already hooked.  One of the aspects I really enjoy is building my own antennas.  I had already built a 1/4 wave ground plane vertical that worked quite well, I was able to get contacts out nearly 1000mi when conditions were good.  However, I wanted something with a bit more punch so I decided to build a dipole which would double my gain.

The only problem with a dipole is that it is directional so I would always have a deaf spot of about 30 degrees on each side of the dipole.  I wanted to eliminate that as much as possible so I began to try to work out different ideas.  At first I wanted to run two dipoles that were phased together but I wasn't sure how well it would work and the modeling software really only showed good signal propagation when the two dipoles where half a wavelength apart.  This meant that they needed to be 5.5 m or 18 ft apart.  This would make the antenna quite large and I had a max height of 65 ft as I would be hanging this from a tree outside of my shack.  That wasn't going to work.

Plan B: I dropped the top dipole down to just a couple of feet above the bottom and modeled that in software running only one dipole at a time.  This gave me about 8db gain and solved my 'deaf' problem.  Here is the antenna in the modeling software.

Here is the SWR prediction and gain for several frequencies (26.155 was a typo) with the bottom of the antenna at 18m/60ft 

This is the far field plot of one of the dipoles, you can see at the height of 18m/60ft we get several lobes and a very low take-off angle

2D version of the far field, here I have the bottom most lobe marked and you can see it has 8db of gain @ 8 degrees

Now that my concept was proved I just needed to build it.  The next question was what to build it with.  I figured I could use PVC and pipe to build a structure that would hold up and perform well.  I had initially decided on copper pipe but I found that 1/2 copper pipe was a bit too flimsy for this application and 3/4 pipe was going to be too expensive.  I settled on 1/2 EMT electrical tubing.  This also saved me about $32 just on the elements alone as the 3/4 copper pipe is about $12 and the EMT is about $4.  For the structure of the antenna I decided to use 1" PVC pipe.  In fact, the only elements with metal in them are the small ring I use to connect the antenna to the rope, the elements and the coax.  Everything else is PVC and rigging.

The Build

 Here are all of the parts that I used for this build.

• 4 - 1/2" EMT electrical conduit @ 10 feet
• 4 - 1/2" EMT compression fittings
• 3 - 1" PVC pipe sections @ 2 feet
• 2 - 1" PVC cross connectors
• 2 - 1 1/4" PVC cross connectors
• 4 - 1" PVC plug with 1/2" threaded connection
• 4 - Metal screws
• 1 - Stainless Steel quick link (3/16 I believe)
• Paracord 550lb test, 160lb working load
• 2 - 1" PVC threaded connector (not pictured)
• PVC cement (not pictured)

Additional Misc items

• zip ties
• heat shrink wrap
• hot glue

First step is to build the main body of the antenna.  We will use one 2' section of the PVC pipe and both 1" PVC cross connectors.  We will glue these perpendicular to each other.  This is rather important to the build so I recommend dry fitting them, marking the alignment and then gluing.

Next, we will glue the 1" plug with 1/2" thread into each of the horizontal openings in the cross connectors.

Now we need to drill holes in the top/bottom of the 1 1/4" cross connectors.  Originally I had intended to fit the 1" pipe in snug and glue it in place but found my hole to be a little too large.  Ultimately I ended up using the threaded 1" connector (which I happened to have on hand) to glue into the hole instead.  I think this was the better option.

1 1/4" cross connector with 1" threaded fitting glued in.

This would not work well except that the force we are going to be putting on this connection is going to be in favor of the glue and not working against it.  With that in mind, we move on to the next step.  We will glue the 2' sections of PVC into our fittings that we glued into our 1 1/4" cross. 

For the base we will then take that section and glue it in place opposite of our crosses that the antenna elements will screw into.  This was my attempt at picturing what I am saying.  It will become more apparent later in the build.

Now we can add the top section to match the element fittings. They will be inline with each other to allow the support rigging.  This is what your finished body should look like.

Hopefully here you can see that the top of the body is inline with the element sections and the bottom is offset.

Now we will add the compression fittings to the EMT pipe.  First, prep the end of the pipe with some sand paper to allow for a good electrical connection.  Next, put on the fitting discarding the lock ring as it won't be needed. This is a two wrench job, you'll need something with teeth to grab the fitting and a wrench to get a good tight on the locking nut. **Do this for all four elements**

Now we will cut the EMT pipe to the appropriate length.  My modeling software told me that my element needed to be 2.675m long which is about 105.5 inches so I measured from the end of the fitting to the pipe 106.5 inches to allow myself a bit of room to adjust.  Once they are cut, you just need to screw them into the pvc connector.  Get some help with this part as the antenna quickly becomes a bit unruly.  In fact, so much so that I forgot to take pictures of this part of the build so I'll use some later photos to show what I did.  Work on one set of elements at a time.  Have someone hold one side while you screw in the other.

Next take some of your rope and tie a clove hitch (or your favorite constrictor knot) near the end,I did about 1ft, of the pipe, run the rope through the top cross and tie the other end on the opposite element. I also tied an overhand knot with the slack end of the clove hitch to the main rope to prevent it from working loose.  This will allow the weight of the pipe to be carried by the structure and not put strain on the compression fittings and pvc connectors.  The type of knot is important because you want it to lock onto the pipe and not slide as this will be under constant tension.  Adjust the knots until the two elements are hanging at 90 degrees to the body.  Here is a photo that shows the elements rigged up.

The next step is to add the rigging for hanging the antenna.  I used two separate runs of rope through the bottom cross, up the sides of the body and through the 'elbows' of the top cross.  Where they cross over at the top, I added my quick link.  The ropes are tied together using fisherman's knots on each end so that when they slide together they put tension on each other. Take time to make these as close to the same length as is possible so that you have the best resutls.

Bottom of the antenna body with rigging ran through bottom cross connector.  All of the weight is carried from the bottom.

Top of the rigging showing how the lines pass through the elbow of the top cross and connect with the quick link.

At this point I hung the antenna low to the ground to make it easier to work on.  With the rigging set up this way, all of the weight is carried from the bottom of the antenna.  It is being lifted up into the tree, not pulled.

In the conduit, drill one hole (appropriate size for your screws) in each element.

I am using RG6Q coax for this build.  I was able to get a 500' spool of coax at Home depot for $60.  It's hard to find good numbers on this stuff, but best I can figure, it's somewhere between RG8X and RG213.  I prepped the coax by removing about 5" of sheath from the outside and then began to work back the braid. RG6Q is the quad shield and it has two braids, I used both for the best possible connection.  I recommend gently pushing the braid toward the sheath so that it bunches up then taking a small tool to carefully pull individual sections of the braid out.  I did not do this on the first connection and it took me quite a while longer to deal with the rats nest I created.

At the end of the center conductor I bent it over to allow me to attach it with the screw to the element.  On the braid side, I used a crimp fitting with a appropriately sized hole for my screw.  I attached the coax with zip ties from the top down to help prevent water intrusion, I also used heat shrink wrap to further seal the coax.

Now I zip tied a small loop above the connections and ran the wire down the side into an air choke.  The choke is wrapped around a 4" PVC pipe that I happened to have from a previous build (this can be anything about 4" round which is why it is not included in the parts list.  You could even do this by hand if you want.  The coax is wrapped 6 times and the whole assembly ends up to be about 2.5" wide.

The top of this loop was pulled toward the middle and tied in place before raising the antenna.

Both antennas connected, chokes installed and coax tied to mast with zip ties.

The final touch to prevent water intrusion was to hot glue over top of the connections to the elements.

Here is the finished antenna, ready to be raised.

The antenna is 'done' and could be raised at this point, but I like mine to be a bit more hidden up in the tree so I always cover my antennas with a bit of rust-oleum camouflage paint.

Here is what it looks like after:

And here it is up in the tree:

Additional guy lines are used to prevent/discourage twisting so I have a better idea of which way the antenna is facing.

Now for the testing.  Once I had all of my coax connections made, I moved on to SWR testing.  Here are the results:

• CH1 26.965 - 1.3:1
• CH40 27.405 - 1:1
• CH16 27.155 - 1.2:1

For some anecdotal, non-scientific results I can tell you that last night May 19, 2020 I got reports from Ontario Canada (about 650mi) that I was 7x9 loud and clear.  I'd say she's working.  I use an antenna switch to switch between each of the dipoles.  

Gettin' Fit

The dreaded workout, the 10, 20, 30 more than 30? minutes each day that so many people wish would happen by just watching their favorite workout video.

Well, call me weird, but I really am enjoying my workouts now that I'm back into them.  Of course, I'm trying to keep variety and trying to keep the workout reasonably short (I go longer when I have the time).  The longest I've done is 45 minutes.  I think that is pretty good, it's 'nearly' manageable to get it done in the morning before going to work and it typically makes me feel good for the rest of the day.

So, what do I do?  Well, mostly bodyweight exercises, I do have some resistance bands that I picked up from Target and a TRX style device that I made myself following some of the points from these two YouTube videos: Vid1 Vid2.

Here's a quick look at my 'TRX':


It ain't pretty but it get's the job done.  All in it cost me about $15.

I use a couple of phone apps for my workouts.  One is called Updown Fitness, this is by far my favorite app.  You can set up your exercise area dimensions, add in what equipment you have and set your intensity, then the app will generate a workout for you on the fly.  It will do cardio, strength, cross (probably crossfit without having to worry about getting sued) and core.  Let me just tell you that these workouts can and will kick your tail end if you want them to.  I did a 45 minute core workout not too long ago that had my abs tense for days.  It was great.  The other apps I'm still in the process of testing, so I'm not ready to endorse those just yet.  However, do yourself a favor and download updown fitness, you will not regret it.

Currently I'm 'working out' six days a week.  It's not as intense as it might sound, I'm basically doing 3 days of strength training and 3 days of yoga to stretch out.  I'm not a trainer nor am I in super fantastic shape, so take what I say with a grain of salt, but ultimately I think you need to do what will work for you that will also help you to achieve your goal.  I'm thinking about switching this up so I can get some cardio in to help burn fat and increase my overall fitness, but I have to figure out what that will look like.  I'm thinking probably a triple deuce.  Two strength days, two cardio days and two days of yoga to get me limber.

Yoga is a spot where I'm struggling, I'm finding it hard to find a program that I like that provides me with what I'm looking for.  The last one I just deleted off of my phone was called Yoga Monkey and I was pretty good with it until it started telling me that my body isn't mine and I don't exist or some strange thing like that.  Uh? No thanks, just here for the workout and the stretch you can keep your mysticism.  Anyway, trying out a couple of others and will update here when I find something useful.

So, the take away from this is that I think it doesn't matter too much what you do (to a degree) so long as you are doing something.  If you only can carve out 10 minutes each day for a workout, then rock those 10 minutes and get yourself moving, you may find that you want to increase the time you work out as you begin to see results.  I started off at about 15 minutes and now 45 to an hour is what I am trying to shoot for.  I love it and it has definitely improved my mental and physical state.

The Very First Post

Well, before I came up with a name for this blog I totally knew what I was going to write for this first post, now that I'm actually here, I'm struggling.  Go figure.  Did you read the name?  

Who am I?  Nobody special, just some guy who has an opinion on almost everything.  Who doesn't right?  I like to write things out, it seems that I communicate better that way.  My hope is that this will be a place where I can offload some of the hundreds of things I think about on a daily basis.  Some will be interesting, some won't.  I'm 100% certain that some of the things I will likely write about and my stance or opinion on them will make some people angry.

For the last decade or so I've been working in the IT field, while it is very good work and pays extremely well, I find myself struggling to remain focused in my work.  It is also very difficult to remain interested in the copious amount of training and studying that must be done to stay relevant in this field.  All of that to say that my hope is this shotgun approach to offloading things that happen inside my cranial cavity will help me to see where I should focus the bulk of my energy in regard to my path forward.  Maybe I'll find that I gravitate toward politics, maybe homesteading, theology, history, entertainment, law and so on.  Perhaps writing will create a recognizable pattern that I can then use to regain focus in my career and make a change if necessary.  You're fully welcome to come along for the ride, that is all.