Tuesday, December 13, 2011

Chipping away slowly at 80 metres

The ground-mounted Butternut.
Recently I took it upon myself to have another look at the old Butternut HFV6, which has been a major performer for me here at the shack over the past two years. It had snapped for a second time during a wind storm and this time I had written it off, but something told me I should try to get it back up and running again, especially as it might be helpful to me on 80m.

So I ground-mounted it this time. Previously it had been bolted to a garden wall about 5ft off the ground. I put in a good ground spike and also ran a couple of radials, one of which was approximately one quarter wave on 80m. After a session of RTFM (Reading The Feckin Manual!) I discovered that I was able to tune the Butternut quite flat in the middle of the 80m band. 3.650 is not a great frequency to be resonant on. If there were going to be new countries to be worked, they would either be on the CW portion just above 3.500 or at the DX end of the band near 3.800.

After some experimenting with the 80m coil, plus the Q coil, I found I was able to get a 1.5:1 SWR around 3.515. This was fantastic. I could tune up the Acom 1000 and managed to get 400 watts out. So over the past week or so since I finally got back up and running on 80m, I have increased my tally of countries worked from 87 to 95. Eight new ones in a week!!

Now,  tonight, I have discovered the exact right settings for the 80m coil for both the CW end and the DX end. I nabbed SV9IOM just a few moments ago on the top end of the band with 400 watts for a new one. It's not the most practical thing in the world to have to adjust a nut on a coil in the dark every time I want to jump from CW to SSB, but it's a solution nonetheless and allows me 80m action whether I'm in the mood for CW or SSB. All I need is a torch and a small pair of pliers!!

I am thrilled to be back up and running finally on 80m. I hope to work DXCC on that band and maybe get my total number of confirmations up from the current 55, which is quite low. We'll see how it goes. I need some solution for listening though. At just 26ft tall, the Butternut HFV6 is not very sufficient for picking up weak DX on 80 so I will maybe have to put up a long listening wire or make some sort of loop. Suggestions welcome. Bear in mind that my garden is 35ft long x 25ft wide!!

6 comments:

  1. Good morning Anthony, good to hear you were able to fix the antenna and get it up and going. Hopefully this new location will get you much longer life out of the antenna with it getting damaged.

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  2. It does not bend quite so badly during windy conditions now because it is partly shielded by garden walls. It's definitely not in an ideal location still, plus it only has two radials, but it seems to be getting out well with a few hundred watts. All I need now is a decent listening antenna!

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  3. True it may not be the best place but then again it's better to have the antenna up in a so so place than in the best place and blown down.

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  4. Interesting stuff, Anthony! I had worked 40+ countries with windom-type antennas until this autumn. Just a few weeks ago I installed my first real antenna for 80m, which is a full band vertical delta loop, with the top of the triangle downwards. The antenna is fed from the bottom. Immediately I started working DX, NA, UA0, UA9, Africa. Now I have those 55 DXCC on the band, but the number is increasing all the time. Especially the listening is very easy with a loop...almost no QRN!

    My next experiment would be using a GP (I have high trees), and comparing loops and GPs.

    My blog: http://oh3ggq.blogspot.com

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  5. Karhu, how big is the loop? Do you have pictures that I can see? I would love to be able to hear the weak DX on 80 with low QRN !

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  6. Difficult to take pictures of the whole, but something here: http://oh3ggq.blogspot.com/2011/11/inverted-delta-loop-for-80m-and-other.html

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