Tag Archives: end fed vertical

Fixes to the EFHW Matchbox

I have decided to use the EFHW antenna as my primary portable antenna. My previous reports on this antenna have centered around testing on 20m which performed quite well. I want to set this up now for multi-band operation using connection links to add or remove wire as needed to tune it on a specific band. The capacitor I used tested between 9.5pF and 310pF which would let me operate between 40m and 10m. I was disappointed to find the matchbox would barely tune up 10m and would not come even close to 40m. I originally suspected stray capacitance and yes some did exist but what I found today solved the mystery. Turns out that I had connected to the wrong lug of the capacitor which limited the upper capacitance to around 100pF. I changed the connection point and am now able to tune down to 40m but have lost 12m and 10m as there is added capacitance on the low end as well. So my plan now is to run this match box on 40m, 20m, 17m and 15m which should be a pretty good range for this point in the solar cycle. The 40m half wave will be ~ 66 feet long so I’ll likely figure a way to configure that as either an inverted L or as an inverted V.  All other configurations will be as verticals. Next step is to cut a wire length for 15m then add wire to get to each of the successive bands. Band changes will require taking it up and down but it will be resonant. The backup antenna will be the end fed 9:1 matchbox and a tuner. Both will fit nicely into the soon to be reconfigured go-box.

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Next Iteration of the Vertical Antenna – End Fed with Radial Field

I reconfigured the 40m 1/4 wave vertical as and end fed vertical by removing the 1:1 choke balun and installing the 9:1 matchbox as before. One big difference was that I connected the radial field to the ground lug of the matchbox. I have run 24 hours WSPR on 20m with the following results:

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Not bad at all with 132 unique spots thus far (on a fairly bad day of propagation indices). Will try this on other bands soon.

Annual Yard Clean Up is Finished…Well Almost

Took some time over the last few days to get the yard cleaned up and trees pruned. Although the National Weather Service shows our precipitation year to date tracking as normal for the area, it just seems dry. April May and June are wet months for us so hopefully it will pick up. The impact all thi shas on my ham radio activities is that I had to pull up my test vertical antenna and the ground radials in order to cut the grass. Now that all this is done I can look at installing the radials permanently. All of this is in advance of testing some more verticals before I install the S9V31 antenna permanently. Currently I am planning to try the vertical as a resonant 40m/15m antenna with radials, the end fed antenna with the 9:1 matchbox connected to the ground radial field and finally the s9v31 with a remote tuner and the radial field. Overall I am getting close to completing my tests and getting my final configuration on the air.

Vertical End Fed Antenna on 40m

The vertical end fed antenna using the 9:1 matchbox and 30 feet of wire has looks like a winner on 40m WSPR. It did not make the WSPR challenge board but has shown a respectable 120 unique contacts and a nice spread of DX stations.The mast has held up nicely with a bit of electrical tape at the joints. Here is the 24-hour WSPR map:

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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 proceeds on the 30 foot Vertical

I setup the travel mast as before with 30 ft of #16 wire strung up vertically. This time I connected it to a 4:1 balun and added 12, 16 ft radials layed out on the grass. Where there is little space I just wrapped and folded the radials to fit the available space. It is located about 20 feet from the house. This is a temporary rig to evaluate its performance versus the end feed version. Right now I am running 1W WSPR on the 20m band. Here is the 24 hour performance:

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This worked out to 108 unique spots…not enough to make the challenge board but still respectable. Will complete these next 24 houyrs at 00:00 UTC and then switch to 40m for two days. I’ll then do the same with the end fed match box.

New Antenna Shootout in the Works

We are sinking into the low period of the sun cycle and the bands have been reflecting the changes. 12m and 10m are largely closed these days. 15m opens sporadically. 17m is ok during the day but isn’t what it was a few months ago. 40m and 20m are the workhorses these days so I am looking at getting an antenna up that will help run on those bands in particular. I was very enthused by the results on WSPR on 20m of the end fed vertical. I am looking at making this a bit more permanent. I have an S9V31+ that has been gathering dust since I bought it. My plan is to set it up here at the QTH. The thing I am going to be evaluating is whether to run it as an end fed or a 1/4 wave vertical with radials. The only reason I am considering the end fed version is that I don’t have a lot of room for radials thanks to some landscaping and pavers in the backyard. I have setup the travel mast again as an end fed vertical using the Ultimax 100 matchbox. I am running WSPR on it over the next few days on various bands to collect some data. I’ll then lay some short radials and run the same length as a 1/4 wave vertical with a 4:1 balun.I expect very similar performance but the data will tell the tale.Whatever works best will be how I configure the S9V31+.

I ran some SSB contacts with it this afternoon on 20m with some good signals reports coming from Nebraska. Also running A vs B against my horizontal end fed was showing about a 2-3 S unit difference in the noise floor with the vertical. I’ll be working to evaluate that as well.

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.

Test of 45W portable solar Station

I finally got my solar powered portable station out for a full power test. For this test I used the DXextreme 100 with a 33 foot wire setup in vertical configuration. The SOTAbeams portable mast was used to hold the wire up. This was feed with 50 feet of RG-8X coax. I used the FT-817ND with the amplifier and ran it this time on the full power 45W. This was powered as before with the two 12V 7Ahr gel cells and the 55W folding solar panel. Band conditions were not too bad today but there were few stations on the air. I worked outside for about 2 hours today and made four solid contacts. My signal was reported between 53 and 59 depending on the station I contacted. All were domestic contacts. I did hear some stations in South America on 15m but they could not hear me.

Power wise, I consumed 1.1Ahr and put in .3Ahr from the solar supply.That being said I was able to transmit fine with the batteries peaking at about 8.5A. Overall a successful test! Next step is to try this with the Buddipole/Buddistick as well.

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Magnetic Loop vs Vertical Shootout

Had a shootout test between the magnetic loop antenna and a 30ft end fed vertical using the Ultimax 100 matchbox. I configured the magnetic loop antenna for operation between 15 and 20m. The vertical used the SOTA beams 30 ft travel mast lashed to a chain link fence post. The radiating wire was a 30 foot length of stranded 16 gauge speaker wire.50 ft of RG-8X was run to the rig. Both antennas were run through a manual A/B antenna switch. The End fed used the Z817 autotuner to find a match.

The first thing I noticed is that there is considerably less noise using the magnetic loop.This is likely due to the nulls that are broadside to the loop while the vertical has an omni pattern. The lower noise makes it easier to hear weak stations on the mag loop.

I made a contact with a station in Washington state and asked him to let me switch back and forth. The signal report was 53 on both antennas. This was with 5W in on 17m. Overall, did not detect much different between the two except for the noise levels.

So for portable use, the Magnetic loop antenna has a few advanatages:

  1. Easy setup (less than 5 minutes)
  2. Low receive noise
  3. Some directionality
  4. No External tuner required (tuner built in to antenna)

For the end fed vertical:

  1. Easy band change from 80m thru 10m using the external autotuner
  2. Can run higher power than current Mag loop
  3. Broadband: generally does not require retuning within the band.

I will still likely favor the magnetic loop over the end fed vertical due to its ease of setup. It is good to know that the vertical works just as well.