Finding PE4BAS

Fellow blogger and radio addict Bas, PE4BAS is on holiday. To keep his followers busy he created a little puzzle to solve: where am I?

I am always in for solving puzzles.. so here goes.

As he is a WSPR user (I think our first conversation was about visualising WSPR contacts), he can of course be found in the database. 

He is being spotted as we speak:
2017-04-26 12:26 OZ/PE4BAS 7.040044 -2 0 JO56jl 5 OH2EAT KP20xw 1003 54

So, Bas is in OZ and in JO56jl to be more precisely.  That square is not that big and there is not a lot going on there. So I sneaked around and took a picture of his place while he was not looking:

OZ/PE4BAS

Looks familiar?

I had a look around (I hope Bas doesn't mind) and it indeed is a cosy place.

Cosy place Bas has chosen as temporay QTH

I left him alone again to enjoy the rest of his holidays. Thanks for the puzzle Bas & have fun!

Spending a lot of time at PAFF-0097

Just got home from a nice activity at PAFF-0097 as PC44FF. I brought my hexbeam but the parking I had in mind when planning the activity was too crowded. Driving around I was lucky to find a nice open space to set it up. There were some rain and hail clouds around and I was just in time setting up the beam to stay dry.

/P DX antenna

The skies cleared later on

I started out on 20m with the hexbeam pointing to NA. The band was not in a very good shape so the going was slow but I did copy a lot of NA stations (relatively). I tried a sked with VK4FW but the band was just not good enough. After 2 hours mostly on 20m - I tried 17m but that was no fun - I had logged 106 QSOs. 36 of those were with NA stations from 14 US states and 3 VE provinces. Quite a lot of familiar NA chasers in the meantime.

Personally I am OK with an activity once I reach 100 QSOs. However, as 20m was rather slow and I had not copied a lot of the familiar EU chasers, I decided to stay a little longer to try 40m. I took down the hexbeam and set up a 40m vertical (EFHW) on my 18m Spiderbeam pole. In about 45 minutes I was good to go again.

18m Spiderbeam pole with an EFHW for 40m

40m was very noisy where I was. It was due to splatter (a combination of a good rx antenna and poor filters in my FT857d) but also QRN. I changed frequencies a few times but then decided I would have to just bear the noise. It was really busy though. As signals were rather strong I could copy a lot of stations above all the noise. As chasers kept on calling there was no way for me to leave. It was getting dark and far past my negotiated return time but you can't just ignore a pile-up of chasers (well, I can't).

After 2 hours the pile up thinned and the signals dropped below the QRM level. By then I had logged 238 QSOs on 40m - apart from 4Z and SU all of them EU chasers. This makes for a total of 344 QSOs for this activity with 6 park to park contacts. A lot more than I had anticipated. 

Driving home in the dark I saw a lot of huge bonfires and remembered that in this part of the country it is tradition to make large Easter fires. It made it a magical drive home with my ears still buzzing from all the noise.

Magical views driving home

YNOMY LX-pedition planned for May

In preparation of our expedition to BS7 or P5 sometime in the future, YNOMY DX group has planned its first group expedition. So far we have all been active from various places outside of PA individually. As a contest team we have shown to be able to work together for a couple of years already with rather acceptable results.

So now we are off to our first team expedition on May 20 and 21. We chose LX as a convenient location and we chose WWFF as the focus of our operation. Working together with the LXFF coordinator, Mill LX1CC, we have made some draft plans and acquired a special callsign to be used for this expedition: LX44FF.

Our goal is to work as many chasers as we can from Saturday morning till Sunday evening using multiple stations both on phone and CW on whatever band is open between 80m - 2m. We will also issue an award to the most active chasers - check out: LX44FF Award

Really looking forward to a whole weekend of LXFF. Let's hope conditions are acceptable or better.

Project - Mast support for heavy masts

For my portable endeavors I have built an aluminum push up mast and I have bought various fiberglass poles from Spiderbeam. I actually started out with a 10m pole from Spieth. That was rather thin, so I went for the 12m HD version from Spiderbeam.
To get my inverted v's for the low bands up higher I then bought the 18m version and recently I went even further and got myself the tallest pole they sell - 26m.  

Heavy masts present a challenge when working /P. I can manage to set up the 18m pole in the open field on my own but it is quite a bit of work and it would be a really daunting task with the aluminum mast and the 26m pole. [Note that I managed to do just that - setting up a 26m pole on my own in the field: https://www.ph0no.net/2017/10/one-man-set-up-for-26m-spiderbeam-pole.html]

When I built the aluminum mast I went looking for a proper mast support that I could use with my car. Typically this would mean a drive-on support. The ones I found on the internet however were too light for my sturdy (and heavy) mast.

Not having any welding tools available to me at the time (I now have an arc welding machine), I decided to build something myself out of wood. After some experimentation I went for a design where I attach the support to the wheel using lashing strap, instead of driving on the support.

If you are reading this to try something yourself, keep in mind this design only works if you have spoke rims on your car.

I never got around to write something about this support, even though I got questions about the design. After buying the 26m pole I had to build a new support - for a much larger diameter mast - so I decided to take some pictures in the process.

The end result looks something like this (showing my first version):

The tried and trusted version from different angles - note the rubber pads that go between the support and the car tire:

I constructed the old one for my aluminum mast that has a diameter of 70mm. It can also hold the 18m Spiderbeam fiberglass pole. Conveniently the tall vertical wooden beams are the same width as the bottom segment of the mast. This means that the only spacing that is critical when you build it, is the spacing between the two vertical wooden beams.

Now for the 26m I built the same support but I could not find wooden beams of the desired width, so I used the nearest (smaller) width and added planks to end up with the correct width - as you can see in the picture below.

Wooden parts cut to desired lengths 

Now that the vertical beams are of the correct width, the only spacing you have to worry about is the one between the two vertical wooden beams. I used the bottom segment of the Spiderbeam pole to define the space, as shown below.

The length of the horizontal wooden beams is not critical. They define the space between the car tire and the mast / pole. I use an extra 130 mm to leave enough room for my shoes - so that I can use the support to position myself higher when I push out the mast segments.

The height of the upper horizontal beam is critical in the sense that you need to make sure it stays within the height of the car tire (more about that later).

Once all the horizontal beams have been added the support looks something like this:

What is left, is adding the frame that you can tie to your car rim. I use 44x44mm wooden beam for this frame. The height and width for this last rectangular frame have already been defined by the structure you have created so far. It is therefore important that the upper horizontal beam I referred to earlier, is positioned at a height that puts the top of the frame we are now going to add right against the rubber of your car tire.

When I completed this stage I took two more steps: a piece of (ply)wood on the bottom of the support - this keeps the mast / pole from getting stuck in the ground (e.g. in case of a muddy underground). And I add pieces of rubber that go between the car tire and the wooden frame (refer to the pictures above of the old version).

Now you have the lower support for your mast. This might be enough to keep your mast straight up. In my case I added a second support on the roof of the car. This helps keep the heavier masts (like my aluminum mast and the 26m Spiderbeam pole) straight up without guying. 

This roof support is nothing magical. It is simply a wooden beam (44x44mm) that is longer than the width of your car + the distance to the mast. At one end I add two pieces of wood at a distance that equals the width of the mast. Through these pieces of wood I put a threaded rod (M8). This rod is positioned at such a distance that it keeps the mast in place. I use some pvc pipe to keep the keep the sharpish threads from damaging my mast / pole. This roof support looks like this:

I use lashing strap to attach the support to a roof rack on my car.  

Project - DIY aluminium push up mast

Working portable a lot I was looking for a set up that could help me work the DX that I could mostly copy on my vertical end fed wire antennas but that I had a hard time working - especially in a pile-up situation.

I bought the CB yagi first and changed that into a 4 element 10m yagi. Later I bought the folding hexbeam. Both are very nice antennas to work DX.
Of course I could not put these antennas up with the fiberglass poles I use for the end fed wires.

So I set out to find a portable mast that was sturdy enough to set up without guying (under low wind conditions) and could reach at least 10m high.
This turned out to be a challenge. There is not much out there that is strong enough to set up without extensive guying or it is outrageously expensive.

DIY decision
After a while I decided to build a mast myself from aluminium tubes. I could not find the right material around where I live. The challenge is that you need a nice series of diameters with 1-2mm in between the sections. The other challenge is that you do not want to buy 6 meters of each section (which is the default "industry length"). Luckily it turned out there is a webshop for aluminium stuff in The Netherlands that stocks almost all diameters and sells custom lengths.
 
Dimensions
What would be the dimensions to choose if you want a sturdy but still portable mast?
After some experimentation I decided to go for the following series (diameter x thickness in mm): 70x2 - 65x2 - 60x2 - 55x2,5 - 48x2 - 42x2 - 35x2,5

The widest tube is 2 meters long - running up to 2,4 meters length for the last tube. I did this to make sure they collapse together nicely with each narrower tube sticking out the previous one.

Okay. So far, so good.
 
Clamping
Now how do you clamp the tubes together when you want to extend the mast?
For this I used my angle grinder to grind slits into the top of each section. In the most narrow tube I used 4 slits (the gap between the 42 and 35 is larger), for the other sections I used 2 slits. Note: be sure to carefully file the metal afterwards or you will find that the tubes "stick" when you want to extend the mast.

Tube clamps - right one is the new and more durable version

Over this upper part of each section I slid a heavy duty tube clamp. I started using a version I found in a boat shop but they are made of stainless steel. As this is slightly softer the threads of the bolt used to open and tighten the clamp tend to damage quickly. Now I am using a different kind that seem to be more durable (see the picture above).

The end result: mast of 7 aluminium tubes with 6 cable clamps (5 old types, 1 new type)

Proof of the pudding

How does it work in practice?
Well, the mast is a fully manual operation version :)
Extending the tubes can be hard work, especially under windy conditions. In those conditions the mast tends to bend putting a force sideways on the tube you want to extend. This increases the friction.
The best way to extend the mast is to make sure you position yourself on top of anything practical that brings you on a height where the top of the mast is just above your waist. That way you can extend the mast  

Does it need guying?
In conditions of low winds the mast can be extended completely without guying. It needs to be on a level surface though.
When the wind is somewhat stronger I do not extend the last section and still use the mast without guying. At some point it will need guying, either to compensate for not setting the mast perfectly upright or for windy conditions. For this I added a simple and low cost guy ring out of PVC (as can be seen in the picture). It does what it needs to do: act as an attachment point for the guy wires and stay in place while the mast rotates.

I have been using this mast now for more than a year and I am happy with it. When I set it up, I secure it at the base (I built a mast foot from wood that attaches to the wheel of my car) and at the roof of the car (again using a wood construction) I am still considering changing the base I use. I will write about that one another time.

Tips - Setting up the Hexbeam by Folding Antennas

HOW TO FOLD AND UNFOLD THE HEXBEAM IN THE MOST CONVENIENT WAY

As blogged before I got myself the 6 band portable hexbeam by DL1ELU. 

Curious about my experiences? Check out these posts: more experiences with the portable hexbeam (December 2012)  out with the hexbeam, having fun (December 2012)  more hexbeam activity in the sun (March 2013) out with the "hex" again - logging a lot of "new ones" (August 2013) a few hours fishing DX - catching new ones (October 2013)  is it worth taking the hexbeam on short activities? (April 2014)

His manual is very detailed so there is no way that I can add anything useful to that. There are however some tricks to learn about the folding and unfolding of the antenna once you have built it from the kit.

What I want to do here is add my experiences with the setting up of the antenna hoping it will help others who like myself did not really get it right first time. If you have tips that speed up this process, please let me know.

I have added a short YouTube video in which I set up the hexbeam: http://www.ph0no.net/2016/10/ph0no-goes-vlogging.html

Assuming you have put the hexbeam together for the first time, your first challenge is to fold it for storage. So let's start with the folding process.

FOLDING
One important tip: do use a stand of some sort so you can keep the beam upright when folding. I tried it without and ended up with a big wire mess. If you're lucky and your mast goes low enough than leave it on there (mine doesn't - it doesn't go lower than 2m, which means I can't reach the top of the beam). I bring a parasol stand just for the (un)folding.

UPDATE: after a tip of another OM I now use a view pieces of PVC pipe connected to a 5 way fitting (four legs on the ground and one up). This works well, is light and easily transportable. In fact they pipes fit neatly in the Hexbeam bag.
 

Folding 1: Hexbeam unfolded with all wires attached

 Now the first thing I do is to loosen all the joints of the spreaders and fold them down, like so:

Folding 2: Loosening the joints and folding the support elements one by one

I start with the two spreaders where the driving wires run towards the centre post. I try to keep the wires together by guiding them through the nearest joint, like so:

Folding 3: Keeping the wires together

If all joints have been loosened I fold the inner spreaders up and keep them (inner and middle spreaders) in place with a Velcro strap. Like so:

Folding 4: inner and middle spreaders fixed

The parasol stand does a very important job at this point: it keeps wires from ending up on the wrong side of the antenna. If that happens you are in for a nice untangling job later.
The next step I take is folding up the outer spreaders and fixing them with another Velco strap. If you do that you will have something like this:

Folding 5: all spreaders folded

The wires still look like a mess but that will turn out all right. The next step I take is to secure the bottom of the antenna with a Velcro strap. I use this lowest secured point to fold all the wires over and up. Then when I got all the wires up (you would like to have 4 hands at this point, dropping wires all the time) I secure the wires with another Velcro strap somewhere half way up. Now I have a package that looks like this:

Folding 6: wires secured using to straps

Important to check is whether all wire loops are clear from the bottom end of the antenna. If they are not, you will certainly find that a wire has ended up at the wrong side of the antenna, the next time you try to unfold it. So the bottom end of the antenna should look something like this:

Folding 7: no wire loops near the bottom end of the antenna

Okay, now you can put the antenna in the handy bag Christian provides and leave it there till the next activity.

UNFOLDING
So how about unfolding the antenna?

I use the parasol stand as described above. It keeps the wires nicely on the right side of the antenna. When unfolding I unstrap the first two Velcro straps and loosen the wires a bit, making sure they hang freely.
The I unstrap the outer spreaders and let them fold downwards. Like so:

Then I remove the last Velcro strap and fold the inner spreaders down, pushing the outer spreaders outwards. It takes a bit of walking around the antenna and freeing wires that are stuck in joints but in 1 to 2 minutes the antenna looks like this:

The next thing I do is to close the joint between the outer and middle spreaders. Again you need to walk around to free any wires that are stuck in joints or on wire clamps. You end up with a large spider looking structure if you do it like this:

The last step is closing the joints between the inner and middle spreader and moving the completed Hexbeam on to my push up mast. As the antenna weighs next to nothing this is not a very difficult move. It is like walking around with a rather large umbrella.

This process took 15 minutes including taking the pictures. If I solve the folding issue described below I think it can be done faster.

FOLDING ISSUE
I still need to address one issue. I have not fixed the position of the wire clamps. With the folding and unfolding they tend to move a bit. This distorts the delicate balance I created when I first put on all the wires. So now all spreaders bend in different shapes (see the picture below). It is difficult to rebalance the whole antenna and straighten all the spreaders. So in the near future I will remove all the wires and put them on again one by one making sure I fix the wire clamps when I am done (Christian remarked btw that it is wise to fix the wire clamps when you use the antenna for portable operations regularly).

The issue of the bending spreaders

Project - Changing a CB beam into a 10m beam

USING A CHEAP 11M YAGI TO GET A HIGH PERFORMANCE 10M YAGI
(originally posted in June 2012)

As blogged before I got myself a cheap 11 meter 4 element yagi (Sirio SY27-4). I am now in the process of making a manageable yet strong and high enough mast to use in a portable set-up as well as optimising the antenna itself.

Today I started using a modelling program called 4nec2. It took me some time to figure out how to use it but in the meantime I have modelled a few different configurations of the Sirio.

This is what the antenna radiation pattern looks like when used in its original configuration on 27.2Mhz

Horizontal pattern (original)	3d pattern (original)

The main figures for this original configuration @ 27.2Mhz: Gain: 8.39dB, F/B: 18.5dB and beamwidth: 60 degrees.

Paul MM0ZBH advised me to shorten all elements by moving all sections in by fixing them with only one screw (they are normally held by 2 screws per section). This means a reduction of the elements lengths by 8cm. This slightly changes the relative size of the elements (relative to eachother). So I was wondering what would happen to the radiation pattern. It looks like this:

Horizontal pattern (one hole shorter)	3d pattern (one hole shorter)

The main figures for this shortened configuration @ 28.45Mhz: Gain: 8.59dB, F/B: 13.9dB and beam-width: 60 degrees.

Gain is up a bit but F/B ratio suffered from this change. F/B ratio is however not a main concern for me in the portable set-up. To be sure that this configuration would be a good one I also compared this to a completely scaled down version of the antenna - changing the element lengths and boom position by x% based on the higher target frequency. The outcome of this exercise:

Horizontal pattern (scaled down)	3d pattern (scaled down)

The main figures for this scaled down configuration @ 28.45Mhz: Gain: 8.41dB, F/B: 18dB and beam-width: 60 degrees.

The F/B ratio is back up to 18dB. Gain is roughly the same. To me this does not seem like a worthwhile change as it involves adding new holes to the elements. It might be a good step when F/B ratio is relevant.

While researching antenna models I also came across a model designed by DF9CY. Christophe apparently also changed an 11m beam into a 10m one. The radiation pattern of his antenna also looks very good. The position of the elements along the boom is a bit different: the dipole is much closer to the reflector.

The radiation pattern of the DF9CY yagi:

Horizontal pattern (DF9CY)	3d pattern (DF9CY)

Christophe's version performance @ 28.45Mhz: Gain: 8.64dB, F/B: 16.3dB and beam width 60 degrees.
The performance looks a lot like the scaled down version of the Sirio. Christophe achieved a bit more gain while opting for a bit lower F/B ratio.

All in all this tells me that taking the Sirio and changing it by just moving all sections in by one screw hole leads to a very acceptable 10m beam that is hard to beat by any other configuration (if you take the 4m length of the boom as a given). The sigma match for this configuration needs to be 22cm extended for the SWR to be flat around 28.4Mhz.

Another advantage of taking the "one screw hole"-approach is that you can use it the other way around and create a rather decent 12m antenna. If you keep the boom positions as they are and move all sections of all elements out by one screw hole (from the original two screw connection) you get a 12m antenna that works as shown below.

Horizontal pattern (one hole larger, 12m)	3d pattern (one hole larger, 12m)

The performance @ 24.65Mhz: Gain: 7.61dB, F/B: 9.02dB and beam width 60 degrees.
This is not brilliant - especially the F/B ratio is low - but compared to my vertical wire this should deliver a better performance. The question is whether I will be able to tune this antenna using the standard gamma match. Will have to find that out later.

Note that all models above are based on an antenna in free space. If you take the chosen configuration for 10m ("one screw hole shorter") and put it on 6m height (what I am aiming for). You get the following performance:

Horizontal pattern	Vertical pattern

The performance @ 28.45Mhz: Gain: 12.58dB (at 25 degrees), F/B: 15.4dB
At 15 degrees elevation (more relevant for DX) the gain is still 12dB. This should help me to get in touch with some DX.

Update November 2012: In the meantime I built the portable alu mast to hold this antenna. The mast goes up to approx. 13m (43ft) without the need for guying (even with the beam). I used this combination during CQWW SSB 2012. The beam was at that time around 11m (37ft) high. It then has a theoretical gain of 13.6dB at 15 degrees. Perfect for DX-ing on paper but also in practise. Check out my experiences here.