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Little Harbour Cay – NA-054

I activated this cay again this year from the. Shelter on top of the hill. It has good takeoff for both NA and Europe. Unfortunately, after the first day of our activity, the sun decided to let go a huge magnetic storm and the K9 conditions wiped out all of one day and much of the next. However, we got on and made the QSOs that we could.

Here are a few pictures of the QTH and the station.





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Fish Cay – NA-113

I was QRV from Fish Cay today on 15m. What a beautiful place!

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I had a sked with Gordon, G3USR, and managed to work some Russian stations who needed NA–113 as well.

To be honest it was a difficult day. The band was very sporadic with some patchy openings but I made the best of it. I wasn’t helped by my vertical dipole having an

SWR of 1.7:1 up from its usual 1.1:1 😩. I suspect also helped distort my audio later in the session as the battery ran down. Must fiddle with it and see what’s wrong.

Anyway, here are the picture of the working conditions – K3, vertical dipole, 100W from a 35Ah battery. Oh, and the obligatory GPS coordinates to prove I was there 😃

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So that’s NA-113 for another year! I had a blast even though the weather held us hostage for over 1/2 our stay!

CSI – Jamaica Cay

So, if you’ve been following along you’ll know that we’ve been in Acklins Island for nearly a week and, to be honest, I’ve not achieved a lot. You’ll also know that the last 3 or 4 days have been net sheltering from the weather.

That’s the challenging thing about activating islands when you are on your own boat. You are firstly the captain and responsible for your own safety as well as those who are with you. It would also be nice to be able to sleep well and use the boat year after year, so keeping it safe is first and foremost. Amateur Radio comes a distant 3rd or 4th after keeping the XYL happy and other trivia like making sure we have food to eat and complying with local and national administration requirements.

So, if you have google maps or a marine chart to hand, we’ve been to Spring Point, Snug Corner and finally, Jamaica Cay to hide from the
latest round of wind, this time from the east, forecast for 25kt. The forecast was almost right, in fact, it exceeded 30kt at one time.

Now those of you who know the sea will also know that wind acts on water more than just to create waves. The friction actually drives the water downwind. And so it was here too. The Bight of Acklins, where we are, FL22wi, is shallow, very shallow being only up to 5m deep over a vast area.

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So when the wind blows from the east as it has been, the water begins to empty out. We were lucky – over the 2 days of bad easterlies, we only lost 30cm of water but I have a friend that spent 4 days sitting on the bottom at low time since the water left and didn’t come back!

Anyway, things have moderated now so we could actually lower the dinghy safely so it was time to explore Jamaica Cay. We went with our friends Bruce and Val who are accompanying us on this trip. We walked round the island looking for places that might be suitable to plant an antenna and do some IOTA tomorrow. So we find this….

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Yes, it is (or at least seems to be) a human skull. With a hole in it, that seems to have been caused by an impact. There are a few other bones around too! Some leg bones and what looks like part of a pelvis. The police have been called so we will see what happens tomorrow.

To be honest, with the history of the Bahamas, we understand this isn’t that uncommon. We speak to a lot of people, here in the Family Islands. The history is fascinating, the modern history I mean…. There is another Jamaica Cay about 100 mile east of here – it has 2 abandoned tanker lorries on the island – it was a refuelling station for high speed drug smuggling boats I the past.

Maybe catch you on the air this week – band conditions permitting.

73

QRV Hog Cay

imageI was QRV 17m at Hog Cay in the Ragged Islands yesterday (18 Jan) and hope to be again today. Sadly, my first QSO was also my last since my wife fainted but happily she has since recovered. It’s nice and quiet down here – we call it the Hog Cay Yacht Club – the Bahamas tourist authority built the permanent structure for local events and the boaters built the older structure from the flotsam and jetsam that washes up on the other side of the island. Sadly, the takeoff for Europe is not ideal but for the USA, Oceania, Japan and the antipodes it’s great – that also means I don’t have to get up too early 😀 NA-001 isn’t greatly in demand on SSB so I will concentrate on datamodes here with the occasional voice contact.

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A Convenient 10m Antenna

I had an email from, Francesco, IK0FUX, who was interested in the antenna I was using for my 10m QSOs. So I thought I’d just put it here for everyone to see.

It’s a cheeky little number made from 75 ohm coax. I got the design I an email from the RSGB a few years ago and it has been my travelling antenna since then. I recently discovered that I could also use it at low power on 12m as I captured a cheeky RTTY QSO with another DXpedition – I don’t recommend this – my K3 was tolerant – your mileage may vary as they say. I’ve taken the liberty of copying some parts of the RSGB article below.

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Anyway, here is the design. Apparently it’s called an RFD (Resonant Feedline Dipole) and it consists of a quarter wave wire connected to the inner of a 1/4 wave of coax and fed through a choke at the base of the coax. The current on the inner conductor of the coax continues right on up the quarter-wave wire. The current on the inside of the shield now goes back down the outside of the shield.
Now, we want it to stop after going a quarter-wave down the shield.
To do that we put a high impedance choke in its path by winding the
coax into a coil. This does not affect the signal coming down the inside of the cable, but it stops the flow on the outside of the shield. You can also use a choke from G3TXQs web site.

The quarter wave wire cut for 28.5MHz should in theory be 2.63m long. In reality, and if we are using PVC-coated wire (which has a lower
velocity factor) you should really cut it at about 2.5m. You may find that you need to fold it over a little to bring the low SWR point to where you want it in the 10m band once it is installed.
We then solder the quarter wave wire to the INNER of the coax feedline, leaving the outer braid connected to nothing.

Now, we measure 2.5m down the coax and start to create our choke. At this point get hold of a cylinder with a diameter of about about 4.25 inches (112 mm). I used a plastic container I found in the kitchen. Now lay some pre-cut eight-inch strips of gaffer or duct tape on the container with the
adhesive side pointing outwards. You now start winding your choke onto the former – keeping it nice and neat with no space between the turns. In total you need five turns and then you can tape the whole thing neatly together using the gaffer tape. I also superglue the turns together since I found tape tends to stretch and move in high temperatures.

I use this antenna on a 12m spiderpole to elevate it as high as possible, in 9H I use it on top of out block of Flats on an 8m pole. It should have a very low takeoff angle on 10m and I’ve had success working VK long path from C6 (his claim – I guess he has a beam 😃). Either way, signal reports are consistently good but better than the signal reports I can give from it which indicates it may be a little deaf. However, it’s an excellent, robust, portable antenna and if you seal the coax ends then it should not degrade in the weather it’s moisture ingress and the like.

Good luck and Merry Christmas!

NA-048 Activation Approved

I was pleased to have confirmation this evening that the recent activation of NA-048 has been approved by the IOTA Manager, Roger, G3KMA. QSL cards are being printed and Buzz, NI5DX will be distributing them as soon as they arrive.

Buzz has recently been ill and has a significant backlog of QSLs but knowing Buzz, he will clear it as quickly as he is able.

Thank you to those who used OQRS, it really helps streamline the process and get the cards out quicker. Thank you also to those who made donations! That was most unexpected – I hope you won’t be offended if I forward them to a charity.

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Here’s a picture of the QTH at Bimini Sands resort on South Bimini. The place was deserted since its low season. Unfortunately there was no decent shade close to the beach so I had to compromise between optimal antenna position and decent operating conditions. This position worked out well and I was able to work some VK and JA as well as western USA. Takeoff towards Europe was also compromised by the westerly aspect but even so, the vast majority of contacts were with Europe and Western Asia on short path.

Equipment: K3/100, barefoot, vertical dipole on a 12m Spiderpole. Tascam audio interface and N1MM+ with MMTTY. 35Ah battery.

Thanks for all the QSOs – it was fun!

JT-65 and all that…

I’ve been playing a bit with JT over the last few weeks and found it quite enjoyable although since the tempo is not, shall we say, ‘dynamic’ it sometimes quite hard to keep track of whether I’ve saved the QSO or not. That aside, it’s quite fun! Thanks JT.

Now, I subscribe to the Elecraft reflector and a few days ago there was a discussion over whether JT was a weak signal mode or a low power mode. Apparently, there are stations running QRO levels of power in these modes in order to try and ‘force’ some distant wanted DXCC entity into answering them so they can get another tick in the box. Naturally the thread descended into disagreement and accusations of QRM etc.

Never having experienced this style of operating, I was a bit skeptical. However, this afternoon, I got more than I bargained for!
Here is a series of pictures that demonstrate what happens to QRP-level QSOs when the QRO stations ‘forget’ to turn the power down.

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Now, someone is sure to say, I should have my AGC on. Well, yes, I tried that but the effect is that I can’t receive the weak signal that I was working half way round the world. What I can say is that I’m amazed at how robust JT 65 is being able to pick out the weak signal despite the overwhelming strength of signals over 1000 km away. Of course, after a while, it got a bit tiresome for both the DX and myself and we have up. After all extending a 7 minute QSO to something nearer 15 due to QRM is a bit ridiculous!

Most of these pictures were taken when the QSO seemed no longer viable or had been abandoned.

I guess the only guy with an excuse is the 9H station which is on a hilltop within about 8 miles of here – I would totally expect to see a strong signal from him.

In summary, I’m not a bit put off. I had a really nice run much of the morning and look forward to working a few more but I do wonder how workable the mode will be in the long run if people keep throwing power at the DX ‘problem’ rather than patience.