15-40 Meter Spring Loaded Linked Dipole V 2.0

After the trial run of the Linked Dipole over the Easter weekend, several problems emerged, the main one being water entering the feedpoint, the other was not having a clear view as to whether the antenna was on the 15 or 40 meter band.

The water problem was an easy fix, I just changed the feedpoint to a multi purpose one that I had made a few months ago. It can be used either with coax via a SO-239 or fed by Open Wire Feeder using banana plugs. The whole assembly is enclosed in a weatherproof box.

DSCF0013

The second problem was also an easy fix. The original automotive fuse holders have been replaced with heavier duty ones, the type that screw together. These also have a heavier spring in them, requiring a bit more tension to break the connection. They are also a bit easier to waterproof by sealing the top section with Araldite or Silicon sealer.

I also replaced the free floating aluminium connectors with pieces of copper cable that has been soldered to the connection at one end. I have made these 5 mm longer than the original glass fuse to increase the tension needed to break the connection, making it more reliable when the antenna is moving about in the wind.

DSCF0006

Visual indicators were added as well. A strip of reflective tape was added to the 40 meter section so it can be seen at night if the antenna is set for the 15 meter band & is not visible when using 40 meters.

DSCF0011

DSCF0012

After the modifications were made it was back on the MJF antenna analyzer for a check, with both bands reading 1.1:1. Now all that is needed to change bands is increase the tension on the guy rope at one end. A difference of 150 mm is all that is needed to change between 15 & 40 meters. This eliminates the need to lower the whole antenna to change the links.

DSCF0015

Hopefully this version will perform well, I will be giving it a test over the weekend. It will only work as an Inverted V, the weight of the coax when hung as a flatop is too much for the spring loaded connections, but it was designed to be used as an Inverted V, so that is how it will be used.

Feel free to use this design, let me know how it goes!

73`s

Link to Version V.1

Advertisements

4 thoughts on “15-40 Meter Spring Loaded Linked Dipole V 2.0

  1. Pingback: Gwydir River National Park VKFF-593 | VK2FMIA.COM

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

A Nomadic Life

An Australian Travel Blog

MELTING ICE TOWERS

SPARKLING THE CULTURE OF READING AND WRITING

My Garden Biodiversity

My Garden Bio-Diversity

Night Sky in Focus

Astrophotography, visual observation, and equipment modification

HB9DUR

I love ham radio contesting

VK1VIC / VK2VIC Amateur Radio Blog

Summits of the Air , World Wide Flora & Fauna activations, CW (Fists #14192), (SKCC #14993)

VK4FFAB

Photography, Amateur Radio, World Wide Flora & Fauna, 4WDing & Camping

Betweening

Lost, unnoticed and left behind the scenes.

ON TRAIL AND TRACK

Walking Hiking and Photography

Pix to Words

Image ~ Inspiration ~ Insight

Tanza-Longs

Our African Adventure in Mwanza and Beyond

penbookcamera

Discovering photography, writing, and life

Wild Radiance Photography

To photograph, to educate, and to preserve.

Becoming is Superior to Being

I come closest to succeeding by sharing.

CJ BANE & PEARL

Leave nothing but footsteps. Take nothing but photos. Kill nothing but time.

Cristina Stamate Photography

"Your first 10.000 photographs are your worst." Henri Cartier-Bresson

eeva-maria

snapshot

Picture Perfect Memories for life

Myriad memories frozen in time

%d bloggers like this: