Dipole antenna-center, part 2.

I received the antenna-centers from Shapeways today, it didn´t take more than a week from idea to actual device in hand. Initial testing show them to be a success, and just as I expected them. Now I can easily make portable antennas, without having to tie wires in knots and rats-nests to make them. The weight go them is around 5 grams each, so they´re not really noticeable even on hikes in the wilderness with a heavy backpack.

They are made in what Shapeways calls "Strong & Flexible Plastic", which is laser-sintered nylon. How they will stand up to UV I have no idea, but these things are for portable use mostly, and they´ll last for years anyway.

Threading 300 ohm twin-lead inside the dipole-center.

A very simple dipole setup. 

If you want one, they are available online from Shapeways here :

http://www.shapeways.com/shops/gisles

Dipole antenna-center design

A while ago I needed to make myself a new portable mulitband dipole for field use. I decided that I wanted to try twin-lead feeder, giving me an antenna similar to the G5RV. I cut out a dipole center out of some plastic I had lying around, and used strips to fasten the feeder to it. Needless to say it didn't look very good, but it worked. An excellent companion for my Elecraft KX3.

To be able to make more of those antennas, I designed a dipole center in CAD, and had it manufactured by Shapeways. I will receive the first samples in a few weeks, and will post a review when I get them.

If you want to try one for yourself, you can actually also order one directly from Shapeways here:
http://www.shapeways.com/shops/gisles

Cushcraft R8 vertical - five years on.

In 2007 I moved into a new house. I didn't get the chance to put up any real antennas until the summer of 2008. I had already decided on a vertical, i addition to a small beam (MA5B) and a Windom (FD-4). I spent quite a bit of time figuring out which antenna to get, and I at last decided on the Cushcraft R8. Mostly because it had 40 and 30, and also because it is made up of halfwave endfed dipoles needing no radials. The only thing that kept coming back in reviews was the antenna "going banana" after a while if not guyed properly - meaning it started to sag to the shape of a banana. Of course the only people writing reviews, often seem to be the ones that have something to complain about, so I decided to give it a go. I mounted it on the apex of my roof, and used thin braided nylon flagropes as guys to "de-banana" it on two sides. Setting up proper guying on all sides was out of the question, and the nylon ropes I used are not very tight.

R8 - no banana.

The antenna has been up for five years as I write this , and there have been no problems whatsoever. No "bananaing", no corrosion, no breakage, no nothing. I assembled it, put it up, and there it still is. The climate up here in Norway is harsh, ranging from severe rain- and windstorms, via hot very sunny summer days to severe ice-storms - and all in between.

The braided nylon "guys"

Closeup of the matching box

LA5EKA/MM QRV in the Barents Sea

I am QRV in the Barents Sea until October 8th aboard the HU Sverdrup II. Equipment is the Elecraft KX3, LA1IC 2x12.5m trap (W3DZZ) antenna and the Begali Magnetic Traveller Light. Conditions are so so, but right now there is an opening on ten to Southern Europe. 

I had forgotten to bring my KXUSB cable for this trip, so I had to make a serialcable following this pinout :

Image by Elecraft. Works like a charm. Luckily we had a bunch of serial to USB converters onboard, so I can use it with my laptop. I use Logger32 for logging by the way. 

Migrating from website to blog.

I will slowly migrate my almost 16 year old website to the blog-format. Hopefully this will be easier to maintain, and also be more interesting to the readers. See pages with LA-HamBase 2012 for info about and download of the software.

Delorme InReach SE

I decided to retire my trusty old Iridium 9505A and replace it with a Delorme InReach SE. I seldom needed the phone part of the 9505A, and the messaging was cumbersome (and the subscription expensive).

Ordering the unit was a breeze, it arrived by courier here in Norway after five days.

My initial impressions were that the system is a bit unusual, since all the messages are sent through a Delorme server, and you can´t actually send text messages or emails directly. The receiving end of the message must have a broadband internet connection to be able to see your position and interact with you. It is possible to send SMS-messages to mobile phones, but the position isn´t added in the message, leaving you to type it in manually. This all means, that to be able to send a message from the InReach SE to anyone in the field, the receiver either needs an internet connection, or mobile phone coverage at the least. The only possibility to send messages between two stations outside mobile coverage, would be if they both have an InReach SE unit.

Anyway, I mostly use the unit for telling my wife and friends where I am and that I´m OK, so for me the unit fulfills my needs. The subscription fee is acceptable, and I have unlimited tracking points available.

InReach SE mounted on my bike saddlebag

The battery life expectancy is around 100 hours, and it´s easy to charge it in the field if you bring along a external battery. It´s lightweight, waterproof and easy to carry around, either on my backpack while hiking, my belt while running or on my bike saddlebag while biking. That way my wife or friends can easily track me and get in touch with me when I´m out and about.

To see where I am (if the system is enabled) check out my MapShare page. You might need a password, depending on time and situation.