Saturday, 2 May 2015

Buddipole Experiments

A dirty truck bed!!
It’s a beautiful day here in Kingston, blue skies and 17C, just a great spring day.  In fact it was so nice I decided that today would be a good day to conduct some trials with my stockpile of Buddipole parts.

I have been looking on the internet over the past few months for information on the new shock corded adjustable whips, and have found almost nothing on them, including just minimal information on the Buddipole site itself.  I did talk to Chris Drummond, W6HFP, the owner of Buddipole about the lack of resources and he agreed that there was very little out there.  I did ask Chris if he could put some baseline seeing on the company website to at least give us all a starting point to start our experiments, and he said he would.

So, armed with a copy of the book written by Scott, NE1RD, “Buddipole in the Field” I collected all my antenna parts and off to the garage and my gravel driveway I went.  If you have not downloaded a copy of Scott’s book I recommend you do.  It’s available as a free download from the Buddipole website.  This book is a great place to pick up the information to build better Buddipole antennas, and it also gives you a basis for experimenting with the extra parts.

My Buddipole parts box consists of a Standard Buddipole kit, two extra 22” arms, a TRSB, a 12’ Shock cord whip, a 9 section mini-shock cord whip, and a 5 section rigid shock cord adjustable whip.  I also have a mini-coil, two regular coils and a low band coil, and a set of 9.5’ long whips.  More than enough to build any antenna I will need.

My goal today was to figure out some workable ¼ wave vertical antennas where I didn’t have to use any coils. I wanted full sized antennas with no compromises.  Today I looked at 10m, 12m, 15m, 17m, and 20m. 

The standard items that remained constant throughout the tests were each antenna was mounted on an 8’ painter pole, and it was done over average ground.

The first test, on 10m, was done using the mini shock corded whip.  It took several attempts to get this antenna to the point it was useable.  Here are some numbers:

Using the mini shock corded whip, with no stinger used, at 28.500 the SWR was 5.7:1 with a counterpoise of 8’ 4”.

Using the mini shock corded whip, with the 9” stinger extended, at 28.500 the SWR was 7.0:1 with a counterpoise of 8’ 4”.

Using the mini shock corded whip, with the 9” stinger extended, the small coil at tap 3, and at 28.500 the SWR was 8.4:1 with a counterpoise of 8’ 4”.
 
Obviously the standard setting was just not working for me today, so I changed things up.  I used the mini shock corded whip, with no stinger used.  At 28.500 the SWR was 2.6:1 with a counterpoise of 6’ 11”.   And that was as low as I could get the SWR on 10m, but to be fair the antenna is a bit long for the band.

The next test was for 12m, not a band I use very often but I have made some great DX contacts there.

Using a 5-section rigid shock cord adjustable whip, with no stinger used, at 24.950 the SWR was 1.4:1 with a counterpoise of 8’ 4”.  No point messing with this one as I don’t think I could get it closer to one to one.

Next up was 15m, a band I use quite a bit for chasing European DX. 

The Buddipole TRSB
Using a 5-section rigid shock cord adjustable whip, with 4.5” of the top stinger used, one 22” arm and the TRSB set at 2:1.  At 21.175 the SWR was 2.1:1 with a counterpoise of 12’. 

Next was 17m and a band I like and use a lot,

Using a 5-section rigid shock cord adjustable whip, with 5.0” of the top stinger used, two 22” arms and the TRSB set at 2:1.  At 18.136 the SWR was 1.9:1 with a counterpoise of 12’.   I messed with this antenna for quite some time moving the counterpoise length up and down, and I could not get a better SWR reading.

Last up was the 20m antenna.

Using the 12’ shock cord whip, two 22” arms and the TRSB set at 4:1.  At 14.150 the SWR was 3.3:1 with a counterpoise of 15.6’.   No matter what I did with the counterpoise length I could not get the SWR any better.


It was interesting that most of my counterpoise lengths are very different from what is recommended in “Buddipole in the Field” by Scott, NE1RD, by a good margin.  It would be interesting to hear what sort of ground Scott as using when he did his experiments.  From what I saw today it is very true that the counterpoise lengths are very critical to the tuning of these verticals.

Obviously there is still some more experimenting to do, but these are a starting point and  enough to get me on the air quickly.  Still to come are the 40m, 60m, and 80m antenna configurations.

If anyone has any ideas to make these settings better, I'd love to hear about them!


1 comment:

  1. I've helped a friend setup his buddistick a few times. We didn't use a counterpoise, a wire laying against the ground. Using a radial about 1 meter above the ground at 1/4 wave length was like night vs day. And yes, adjusting the tap on the coil was very touchy too. I've buying loving their buddistick and I'm not convinced myself. I'm looking for a shorter option to my trail end fed as some more compact would be nice. 73, chuck/aa0na

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