Saturday, October 29, 2011

Butternut back in action, and resonant on 80, 40 and 30

The new ground-mounted configuration
Following another recent wind storm in which the Butternut HFV6 was snapped again, I decided that I would reinstall it, but this time mounted in the ground. Because the short evenings have returned, the weekend is the only time this work can really be done now, so I tackled it today.

I found a piece of galvanise pipe which just happened to fit snugly into the bottom "mounting pole" of the Butternut, so I hammered this into the ground at the bottom of the garden using a lump hammer. If course this flattened the top of the pipe a bit so after a small amount of sanding I was able to slide the Butternut mounting pole down over it as far as ground level. Then the somewhat shortened Butternut (only about 3cm) was positioned onto the insulator and the Q Base Matching Coil was attached. I also ran one 25ft radial attached to the bottom connector of the Q coil. I know ideally I should have a decent ground system, but a small garden, coupled with the fact the Butternut is in a corner, coupled with the fact I have young kids, means that having wires running all around the garden is simply not practical.

Anyway, I did a small amount of guying work with 50kg fishing tackle, but will look at something more durable down the line. I made a couple of contacts on 80m and 40m after tuning with the FT-1000MP's internal ATU. But then I took it upon myself to do something I have not done properly before - to try to get the Butternut resonant on some of the bands!!

First I tackled 80m by adjusting the large 80m coil assembly to see if I could get a lower SWR somewhere in the middle of the band. As I use both CW and SSB it was not practical to flatten it at one end of the band or the other. I also compressed the Q Base Matching Coil significantly and this brought VSWR to about 1.6:1 on 3.690. Then I decided to try 40m and a small adjustment of the 40m coil gave me a VSWR of about 1.7:1 between 7.100 and 7.200. The SWR rises below this, to a 2:1 at 7.050 and 2.5:1 on 7.005. Not too bad, and nothing the tuner won't handle!!

Then it was onto 30m, where analysis found the Butternut was resonant on about 9.9Mhz. A quick read of the manual revealed that to raise the resonant frequency, the wing nut on the 30m coil assembly should be loosened and the coil stretched. This was done, although there was only a few centimetres available. I came back to the shack to find the antenna resonant without a tuner on the whole band (admittedly 30m is a narrow band). The VSWR reads about 1.3:1 over most of the band, but 1.4:1 at 10.100.

I later checked 20 metres only to find, to my delight, that the Butternut is resonant over the ENTIRE 20m band!!It is also quite flat on much of 15m, although it's 1.9:1 on 21.001 and 1.2:1 on 21.350.

Anyway, I am thrilled to have the Butternut back in action. Admittedly it has not had much use lately since the installation of the MA5B, and the Antron 99 is better on 12m and 10m where conditions have been great. But I have had nothing on 80m recently and missed a chance to work MU/PA9M on that band over the past few nights. So maybe I will nab some new ones on 80m again this winter. I currently have 87 DXCC worked. I would be thrilled to get over the 100 mark this winter.

In the meantime, I will let you know of any interesting contacts I make on the lower bands with the Butternut, which has seen over 20 years of action at various QTHs and is now on its third resurrection at this station!!

PS: Just ran a test with the Reverse Beacon Network on 30m. On the Butternut I was being received by TF3Y at 29dB snr and by KM3T at 9db. On the resonant inverted V I was 31dB with TF3Y and 12dB with KM3T. It's very marginal.

PPS: Worked Japan on 30m CW with the Butternut.

1 comment:

  1. Good Morning Anthony,
    I have recently decided to take my life long passion for radio serious and have started investing in some equipment to get up and running. I hope to be in a position to sit the exam in the new year. For now I am more than satisfied just to listen in and get familiar with the protocol. I purchased two Yaesu sets, FT-757GX for the 10-160 bands and a Yaesu FT-8900R for the 70cms upto the 10mtr. (Quad band set, mobile/base). I also acquired the FC-757AT Yaesu ATU from a friend in the UK and a Kenwood AT-230 manual tuner on ebay.
    Like yourself I have limited space so the best possible Antenna deployment became a no.1 priority. I have a technical background (Electrician & Electronics Technician) but I have absolutely no experience with Radio or Antenna systems. After weeks of research, reading many ARRL publications and basically Googling every site I possibly could I finally came across one of great interest. I decided on purchasing an Alpha Antenna 6-160, which is marketed as "The 6-160 Meter HFJ-Pole". This can be used as a "Fixed" or "Mobile" Antenna & to be honest I am astounded with it's performance.
    It can be deployed in various configurations, mine is strung along under the eves of my roof & finally unto a pole. I paid about Euro 120 or there a bouts and that included shipping from the US. More info from
    It weighs 1.2Kg, configuration is Vertical, Inverted L, or Horizontal or a mix of each as it's pretty forgiving over most bands. Frequency coverage 1.8 to 54 MHz. Power rating 200W and total length 75' but remember in can be deployed in various configurations. Comes complete with feeder line, balun etc.
    More than happy to send you on official specs & pics. if you want. I am on Hotmail,
    Anyway other than that I thoroughly enjoy your blogs, fantastic website to say the least and wish you and all the folks in Dundalk all the best.

    Best Regards & hope to meet you on the waves next year.


    Kieron Riordan, Youghal, Co.Cork.


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