Itinerant Ham

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Monthly Archives: December 2014

Who’s been visiting?

The WordPress.com people prepared a report for the year on blog visitors. I thought it might be interesting to share since it’s not so often you get to discover who else visits particular sites.

since the blog is for informational purposes (as well as the occasional rant), the number of visitors isn’t really too important – at least is not a goal – I just want people to be informed. It’s hardly likely that there will be anything groundbreaking here but on the other hand, if you want to get a new island (rather than island group) in the log then perhaps it’s worth keeping an eye open here.

Happy New Year for 2015 and I hope to work you from somewhere!

Here’s an excerpt:

A New York City subway train holds 1,200 people. This blog was viewed about 4,300 times in 2014. If it were a NYC subway train, it would take about 4 trips to carry that many people.

Click here to see the complete report.

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 โ€“ 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 ๐Ÿ˜ƒ). 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!

NA-048

Today should be the last day on South Bimini island. The weather has finally changed and will allow a departure late tonight or tomorrow morning. Unfortunately the SFI is falling but I am still hopeful for a few hours on 10m this morning preceded by a few skeds.

The conditions over the last few days have been excellent with good openings to Europe and even deep into Eastern Europe after their sunset. Of course, the ‘euro-wall’ effect has been there but working a wide split has allowed more productivity and kept the DQRMers at bay! It also allowed me to deal with the Dutch station that managed to get his rig stuck on transmit repeating his callsign at infinitum and the U.S. Station that managed to use the listening frequency to call CQ! ๐Ÿ˜ฑ

A wide split does not allow the operator to quickly recover from the shock of a gecko biting his big toe mid-pileup! Happily no blood but it definitely caused a pregnant pause!

I have a simple set up here. K3, a 10m vertical dipole and and lead-acid battery in a Tesco bag!

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Thank You

So you’ll have got the idea I was pretty pissed off yesterday by the antics of ‘LA-LA’. ๐Ÿ˜ (even more so when he attempted to say that english wasn’t his mother tongue but no one could have been offended by such constructive comments) ๐Ÿ˜ณ

Happily, I had a bunch of emails that were a lot more encouraging, to say the least! So I set up a bunch of skeds for later in the day and went for a walk with my XYL.

Later, I was tuning about and discovered M0VKC on 12m RTTY. Tempting but I only had my 17m vertical – and by the way, this winter’s challenge is to use only monoband antennas – I don’t have a tuner with me. (By the way #2 is that I only have one spiderpole). So I changed frequency and reduced power to 40w – only 3-1 SWR and no complaints from the K3. Back to M0VKC and a quick QSO ensued! (Shortly followed by an email thanking me for a new one on NA-048).

Back to 17m and I had 2 skeds with UK stations in difficult conditions as the band was closing for them and then a nice run of NA interspersed with some European stations and much to my surprise a VK – long path all the way from Sydney – and louder than the UK stations and many US stations! Well done Nick, VK2DX! Hope you didn’t miss the bus to work!

So thanks for a nice end to the day guys and all your encouraging messages! I’m only slightlyย sorry that I had to quit at 5pm since our neighbour invited us to a (terminal) rum tasting session… Well – I did say ‘vacation-style’ ๐Ÿ˜€

73 – till tomorrow!IMG_0637.JPG

Fan Mail…

I posted this update to the IOTA Chasers group:

“Hi guys,
Hopefully I’ll be QRV again today. I spent several periods on Saturday and Sunday calling CQ on 10m without generating many QSOs so I took the time to do vacation stuff and some antenna work.

When the rain goes off, I’ll be QRV on either 10 or 17m today. I’ll try to send an email to this group before I go.”

I was somewhat surprised to receive this response in the same group.

“CQ WW on CW was last weekend, so It would have been smart to stay on the so called WARC-bands.
The high bands close at abt 17 UTC here. Have you ever tried 30 m ? It is a most reliable band here.

73 Rag la5he”

Well thanks buddy! Few people wouldn’t have noticed the contest – but wait, I don’t do CW so why would that affect me? Oh, maybe it was because the CW contesters like to use the RTTY portion of the bands ๐Ÿ˜

Anyway, apparently I’m not very smart since I didn’t use the WARC bands. Well that may be but why would a CW contest affect me doing SSB on 10m? Why wouldn’t I be just fine when propagation was so good? I don’t really know so I took the time over the last few days to check my antennas and to build a new one.

However, I’ve taken a step back from all that in the light of my “fan” mail and am examining why I am bothering to get all my gear out of the bottom of the boat, drag it 1/2 a mile to a less-than-ideal QTH and sit there in the heat and sand flies.

I mean – really, I doubt I’d get the same amount of abuse if I just sat and drank beer. So I have written to my QSL manager and asked him to put a hold on printing QSL cards for the time being.

So for now, I’m QRT. And for the avoidance of any doubt, it’s not all about propagation to LA-LA land and neither is it all about 30m or CW – a bit of research on Clublog by a not-very-smart ham established that a long time ago.

73