Tag Archives: end fed antenna

Field Day Antenna Selection

Working on Field Day antenna selection this week. I am down to using the Homebrew Buddipole, Buddistick or end fed vertical antenna this year. I plan to operate as 1B battery operation so I am limited to 5W on SSB. This will be my main challenge  this year given the worsening band conditions as the solar cycle continues the drop.

A previous post showed some data on the homebrew Buddipole mounted at 16 ft with a painters pole. I am working on a few tweaks now that will bring resonance into the band and simplify the azimuth adjustments.

The Homebrew Buddistick served me well in 2015 but band conditions are shifting. Here is some modeling data comparing the Buddipole at various heights vs the Buddistick on 20m:

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The Buddipole at 16ft and 20 ft outperforms the Buddistick down to about 25 to 20 degrees. The Buddistick has more gain below these take off angles. At 30 ft the Buddipole is better or equal to the Buddistick from 60 degrees all the way way down to zero.

One thing I could do is use both antennas and switch back and forth as needed. This would not be overly complex to do. My challenge is getting the Buddipole up above 16 ft. If I can get setup using the military poles I can get the Buddipole up to 30 ft and only use the one antenna.

 

 

Testing End Fed on WSPR

I am now testing a variation of the end fed antenna on 20m WSPR. I am using the same length of wire as the EFHW but am now using the 9:1 matchbox. I have 50 ft of coax running to the shack where I am using an autotuner to match. I have an air choke of 6 turns of coax not at the feedpoint but at the shack entrance. This configuration uses the feedline coax as counterpoise.

So far results are very similar to the EFHW but I will wait for two days to collect the final data. Meanwhile, I am going to require the EFHW matchbox to try and get a better match to try again.

Testing End Fed Verticals

I installed a piece of 2″x2″ angle aluminum in the ground outside the shack to support my vertical travel mast. This works very nicely with the tie down straps.

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I tested the EFHW on 20m yesterday on WSPR and found that it was hearing and being heard quite well on 1W. I shifted this to the end fed matchbox that I have had for some time. This requires the tuner but allows for multi-band operation. I used the same wire as the EFHW of around 30 feet. I modified the coax arrangement so that the air chock is at the window panel instead of the feedpoint. This gives the remaining feed line as part of the counterpoise. This seems to work well. I am getting reports comparable to the EFHW on 20m with this antenna. I was able to have a good ragchew with a station in AZ on 100W SSB using this antenna. I am keeping this up through 00UTC today and see if I score in the WSPR Challenge.