Tag Archives: Field Day

40-20-15m EFHW Round 2 – Update

WSPR results o 40m and 20m WSPR look good with the EFHW. here is 40m during nightime hours:

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And 20m for just a few hours yesterday and so far this morning:

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On 40m there have been 103 unique heard vs 106 heard by (@1/2 W). On 20m, this is 124 unique heard vs. 74 heard by (also @1/2 W). These numbers indicate good overall performance.

I found a great write up on how to build one of these antennas titled “A Shortened Multi-band End-Fed half Wave (EFHW) Antenna for 80-10m” by Steve Nichols, G0KYA.

I am going to do some work on how to best deploy this in the field given my typical situation (i.e. lack of tall trees). this could be a great Field Day antenna.

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2017 Field Day Results

New QST came in with the results of this years Field Day. Here is my score. My score is #3 on the following list:

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I was only one of two stations claiming a 1B1 class in the STX section and I had the higher score. Out of all STX stations reportiong across all classes I came in 54 out of 72 stations. In the 1B1 class, I came in at 60 out of 102 stations. Top score had 1371 Q’s! Overall happy with these results considering I only worked FD for about 8 hours and was running 45W on solar charged battery power. Looking forward to improving the score in 2018!

Post Field Day Report

I got a late start to field day this year due to a late breaking family commitment. Our club tried to setup at the local weather station but cancelled operations due to a large noise source crashing the bands at that location.

I started operating about 19:30 UTC. I started at 5W on SSB but over the first hour only made one contact. The band conditions were not good on 20m with lots of QRM and QSB. I added the amplifier and started to work on 45W. My power draw was significantly higher but my Q rate increased. The solar panel kept up with the power consumption even though there was quite a bit of cloudiness. I continued to operate on 20m until dusk when I switched to 40m. Overall I made 60 Phone contacts over the course of about 8 hours. My score this year will be lower even with more Q’s due to the higher power I ran. I did not get a chance to run digital.

What worked:

  1. Digital logging – netbook needed one charge cycle during this period. The 12V to 18V DC-DC converter was running at abou 2.2A during the charging cycle. I used a 7Ahr for this through a spare Solar Charge controller. I am going to look at a tablet for next year.
  2. The EFHW antenna worked great on 20m.
  3. SOTAbeams travel mast + TV tripod worked great to support antenna with no guy lines.
  4. Solar generator box had enough juice to supply the day’s activity even at the higher power consumption and had some power to spare.
  5. Tube Tarp came in real handy as shade. Luckily no rain on Saturday. I’ll do better with the depolyment next time as I figured out how to guy it better.

What did not work so good:

  1. Can’t run digital mode while using an amp. The amp uses the ACC port on the radio but provides no pass through. I am looking at how I can accomplish this for next time.
  2. I don’t have the battery budget to run 45W phone for 24 hours. I figure I would have run out of power after about 12 hours. Partly cloudy day didn’t help.
  3. Didn’t take advantage of more 6 stations to raise Q count.
  4. Calling CQ consumes a lot of power. Need to refactor the power budget.

So I figure my score this year for 60 SSB QSO’s + bonus points for emergency power will work out to 310 for my 1B station. I am convinced now that I have to finish learning CW so that next year I can run 5W on CW and up my point count. A more directional antenna would be nice but a portable beam antenna remains elusive. For some reason I seemed to be doing better with stations in California than on the more densely populated east coast.

In summary, A great afternoon of outdoor radio fun and already looking forward to next year.

Field Day Preps Complete!

My Field Day preps are done. Tested the EFHW and its ready to roll on 20m and 15m. There is 12Ahr of solar charged battery ready as well. I won’t be able to join the club at the NWS office as I have a commitment in the morning I have to deal with. I may start late but I am ready for operations in the backyard. Will get some water bottles and snacks for daytime ops. There is a 30% of rain tomorrow afternoon so I’ll keep an eye on that as well to see if I need to deploy the tarp tent. Rain means clouds so that may help moderate the heat. Today the NWS is advising people to stay indoors between 1pm and 5pm!

Tested the EFHW a bit and am finding Common Mode Current issues if I run higher than 90W. The SWR increases with power and foldback starts kicking in if I try and run at 100W. This should not be a problem on FD as I’ll be running at 5W where everything behaves itself. I’ll be trying computer logging this year as well. If things get real tough on Phone I plan to try PSK31 and have setup some DM78- macros for that.

Looking forward to a great Field Day in the outdoors!

Completed Linked EFHW

I completed the linked EFHW later yesterday afternoon and tuned the 15m, 17m & 20m bands. I removed about 6″ of wire to tune 15m, 2″ to tune 17m and about 3″ to tune 20m. The antenna is deployed vertically on a SOTAbeams Travel pole up 30 feet. I am using a TV mast tripod as a base. In the field I would lash the mast to a fence post or other similar support.

I tested the antenna on my base rig at 100W and made three easy SSB contacts. Two of these were EU DX contacts. I  left it tuned for 20m and ran WSPR for the last 12 hours. Here is the map:

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This works out to 112 unique heard spots with 66 unique heard by spots when running 1/2W. Looks like the antenna is a winner for Field Day! Only thing I will likely try today is adding a 1:1 choke as I am seeing the SWR swing a bit on SSB transmit.

Linked EFHW Coming Together

I purchased the following for $1 at Home Depot yesterday to form links for the EFHW I plan to use for Field Day:

Photo Jun 21, 10 47 20 AM

These are buckles to make paracord bracelets. Here is how the resulting link looks like using these, a couple of cable ties and a pair of Anderson Power Poles:

Photo Jun 21, 11 01 22 AMPhoto Jun 21, 11 01 32 AM

I have made initial wire cuts for 15m, 17m, 20m and 40m. I also cut 1/10 wavelength counterpoise wires for each band. I have also prepped the Travel Mast and the TV Tripod so I will hopefully setup later this afternoon (when it cools off a bit) and tune the wires. I’ll run 15m-20m as a vertical and 40m as an inverted V.

The only other prep I am working on today is I’ve taken the solar generator box I built last year and set it up outside with the two 15W panels to charge them up.

Update: Just did the calculations on the 40m inverted V and found that I probably don’t have enough space to lay that out in the backyard due to obstacles. Will configure the first half as a vertical and then the remaining half as a sloper which I’ll aim towards the north and terminate 4 feet off the ground. Only need a radius of about 16ft. A quick run on EZNEC show the following pattern:

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Plan B for Field Day Antennas

I was pondering what I would do for a Field Day antenna after yesterday’s debacle with the Homebrew Buddipole and military mast. It just hit me a few minutes ago. I’ll run the EFHW antenna as a vertical on 20m and 15m. It is a proven performer and it is resonant thus no tuner needed. I’ll use the TV Mast tripod Cliff gave me to support it during the contest on the SOTABeams Travel mast.  What I will do this week is set that up and cut some links for 15m, 20m and possibly even 40m. Will be much more manageable as a vertical. I have 5 days to work out the details. Tomorrow morning I’ll put put the battery packs and solar panels to top off the charge. This should work!

Epic Fail! – Homebrew Buddipole on Military Mast

I took out the military poles and tripod today for the first time with the intent of getting the homebrew Buddipole up around 30 ft. The mast itself works pretty well with the tripod hub. I mounted the Buddipole on top as I have before with the painters pole except this time I replaced the thread adapter with a 3/4″ PVC pipe adapter and used a length of pipe to fit inside the mast section. I guyed it near the top. I sent it up and it promptly got swung around in the wind and tangled in a tree. After twisting and turning awhile I got it clear and up to 28 ft then tied off the guys. I left the last section off as I did not have enough coax to get it in the shack.

Started operating on SSB and made a strong 59 contact into Arizona then noticed that my SWR was swinging around. Looked outside and saw that one half of the dipole was swinging into more of a v-beam. Moments later it fell off completely. Doh!

Photo Jun 17, 1 25 23 PM

The section landed cleanly and did no damage but I had to take the whole thing down. Guy lines get tangled, the aluminum mast sections are burning hot to the touch and my temper starts flaring. Did I mention it’s 97 degrees outside with 51% humidity?

So I carefully sort out the guy lines, move the tripod a few feet away from the tree and place a wedge in to keep it from swinging as much. Sent it up again and adjusted the guy lines. Went back inside the shack and hooked up the SWR meter. It started a sweep and was looking good when I heard a SNAP and the meter SWR reading went full scale. I looked out the window and sure enough the half of the dipole fell again. On inspection I was not so lucky as I broke the whip off at the base. Doh!

So thus ends my Field Day Preps today.I am goign to use something much simpler next week. Either the Homebrew Buddistick which I have used before, an end fed vertical up about 30 feet or a 1/4 wave vertical for 20m with four ground radials. The Buddipole is going to be limited to lower heights using the painters pole. If I had more time I’d try an inverted V for 20m using the Spiderbeam mast.

 

Buddipole 1:1 Current Balun

Here is the 1:1 Current Balun for the Homebrew Buddipole antenna. I sourced the parts kit from Ebay and just had to assemble it as before. This is ready to test as soon as tomorrow. I am planning to setup the 30 ft military pole with the Buddipole for the first time tomorrow if the wind cooperates. This should work very well at 30 ft!

Photo Jun 13, 2 49 18 PM

Photo Jun 14, 5 25 02 PM

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.