The vertical has had a number of runs since the first post.
I have not actively compared its performance to my end fed antenna. But it seems to be no less efficient as I have worked a few JA station on 18MHz when using it.
The design remains similar with the exception of adding a 1:1 current balun. This was introduced to isolate the coax from the antenna system, as I noted some variation in VSWR as the coax was moved. This was discussed here on the SOTA reflector (look for post #7)
I have remained with the3.7m radials but I have increased the number to 8 (yet to be tested).
After reading An experimental look at ground systems for HF verticals (second link below) I may increase that number to 16.
Naturally the internet is most people go to when it comes to research, to date I have turned up three items of interest
Some Rules of Thumb for Ground Radials
I have also found some interesting reading by Rudy N6LF, Rudy has done a huge amount of work with antennas. two articles caught my with regard to radials for vertical antennas;
First one, on this page look for Series of QEX articles on ground system experiments
The summary of these articles are covered in this document Download QST March 2010 Ground Systems
The second one looks at radial length for shorter verticals, one this page look for Are the lengths of radials related to the height of a vertical? to find the article Vertical height versus radial system
I spotted this on the ABC’s news feed and thought it was worth sharing.
Next Fridays forecast below;
I have often thought of adding a vertical antenna to my SOTA kit for DX use.
This interest was re-kindled when I spotted this kit from Qrp Guys.
The kit also generated discussion on the SOTA Reflector here.
After some thought I settle on a vertical that would cover 15, 17 and 20m with 30m as a maybe.
Base of Antenna
Two SOTA’s and a Park
St Mary Peak vk5/ne-001
St Mary Peak is the highest peak in the Flinders Ranges. It is also one of the few SOTA peaks in the Flinders that is accessible via marked walking track.
Whilst it may only 14.6 Km return via the outside trail, it is still a fair walk with two steep sections which involve a bit of rock scrambling.
Whilst planning a family trip to Eyre Peninsula I was looking for suitable sota summits to activate.
One summit stood out, the unnamed vk5/sw-039 this summit is located within the Lincoln National Park VKFF 0286, but behind the lock gate that allows access to Memory Cove.
Gate to Memory Cove
Andrew VK1AD had posted some VK SOTA stats for the year 2016, looking these it was obvious that no one had activated on 160m in VK.
I made comment about this on the VK SOTA yahoo group, this then turn into a challenge with a weekend selected for 160m activating.
I have used four different radios for my Parks and Summit activation’s.
By far the majority have been done with either of my two KD1JV rigs the MTR and ATS4. Both these rigs run on little power and their compact size makes them quite portable. Batteries are external and if required the ATU is also external. This does make set up a little more time consuming but does provide other advantages such as rig cannot be turn on by accident in the pack, and an external ATU allows the active part of the antenna to be placed a little bit further away from the operator.
ATS4a and MTR 2 bander