Field Day Antenna Plans

aerial photo of the field day site with antenna and ropes superimposed
80/20cw is at lower, righthand corner

Several of the people involved in planning for the VWS field day event came over to my house on Wednesday evening to brainstorm about antennas and setup for the 80/20cw station. By the end of the evening, we had run through quite a few possible configurations, some fancier than others, but in the end we decided to use two dipole antennas. I’ve updated the map showing the layout. Ian’s Buckmaster OCF dipole will run roughly East/West, between ropes suspended from the tree at the top of the hill next to the 80/20 SSB station, and to a tree across the road on the other end.  To help support the antenna, a 40′ double-guyed pole will be positioned near the 80/20cw tent. The same pole will also support one end of a multiband dipole oriented more or less North/South. Between the two antennas, we should have broad coverage (10-80m on the OCF, and 40/20/15/10 on the multiband).

At the station, we’ll have two radios, but only one will be used for transmit (according to the 2011 FD rules, class is determined by number of transmitters). Byron has made available his TenTec Argo VII transceiver, which I believe has been used in previous years as well. At the other position, we will have Jim Nagle’s ICOM 7000. If we have adequate staffing, the other radio can spot, populating the band map, while the other runs a frequency. After the bandmap is full, the second position can efficiently S&P the marked sites, while the other position marks another band.  Since all the band map information is shared on the LAN, we could also mark spots on 40/15, if desired.

I’m still looking for some CW operators for the 80/20cw station — if interested, sign up online or email me.

VWS Field Day 2011: 80/20 Station Planning

It’s about two weeks until Field Day. I’m captain of the 80/20 cw station, and I’m trying to pull together plans for the station. The club has done this event many times in the past, and there is plenty of experience to tap into, which is good, since this is my first time running anything at Field Day. Pete K6BFA is the top boss for the event, but there are a large number of people involved in logistics. A large chunk of the planning took place last month during a walk-through at the site, Burke Lake Park (see map of proposed station locations and antenna deployment). Due to work commitments, I was out of the area on that day, and on every weekend since then. Earlier today, I had a chance to scope out the site for myself. Tomorrow night, I’ve invited people who have signed up to work the station during the contest plus a few members of the planning committee over to my house to talk about antennas for the 80/20cw station, but I wanted to get the lay of the land before the meeting.

The present plan is relatively limited — to run a long wire antenna from a mast near the 80/20 station to a tall tree. It sounds like this would be reasonable for the 80m, although maybe not optimally high near the station end. I’m not sure it would work well for 20m. We have a number of other antennas available to us, plus a push-up 40-foot mast. Also, the station is near the spider beam, which is designated for the ssb station, but perhaps could be shared (?). In pow-wowing about antennas tomorrow night, my goals are:

  1. Put up a single and reliable antenna so we are ready to go when FD starts.
  2. Not interfere with the other stations.
  3. Lay out a strategy for best use of our resources at different times during FD.
  4. Incorporate any experimental suggestions that are not likely to interfere with #1-3.

I went to the site of the 80/20 station, and spun around, capturing the landscape around the site with my cell phone’s camera. The site is a bit lower then the surrounding area, and there is a slight grade upwards to the west. I am initially facing west. At 0:03 seconds, facing the non-40SSB. At 0:06, facing 40/15SSB support tree. At 0:09, facing the tall tree planned to support? the 80/20. Another potential support tree is masked in background at around 0:11 seconds.

I also took some still photos, thinking about trees that might make good antenna supports. Starting with the current plan, there is a really tall oak tree just across the road to the East, in the direction of the minigolf course. We could use a 40 foot mast towards the station end to give it some height. I counted 132 paces over to the tree, so something like 130 meters. A view towards the big oakAccording to the layout picture on google maps, the antenna is about 160 feet, and the support rope about 185 feet (but considerably longer in practice, since it has to go up to the top of the tree and the antenna wire will slope upwards, so not all of its run will contribute to the horizontal distance).

The advantage of this layout is that it should be dead simple to set up. An ICOM AH-4 antenna tuner would be at the tent, tied to a ground, and the single long wire would run up to the mast and then over to the tree.

A number of people have volunteers other antennas for the effort as well, including Ian N0IMB’s Buckmaster OCF dipole, my G5RV, or Byron W4SSY’s 80/20 fan dipole. Of these, the fan dipole may be the most attractive because it is resonant, and perhaps to least likely to interfere with other nearby stations. The difficulty with these antennas is getting the feed point near the 80/20 station.

 

There is another large tree to the South of the large oak, pictured above. On the aerial, the tree is just west of the run of three smaller trees near the road:Another large tree

 

 

A large tree at the top of a slight gradeThe other end of a dipole could be suspended from the large tree just up the hill from the station. According to the site layout, this tree would also support an antenna for the non-40 ssb station. The tree could be used to support a rope, so the two antennas would not be so near each other. Additionally, the two antennas would be near right angles to each other. This end of the antenna would also be near the spiderpole, though, so perhaps that would be a problem.

A view across the field towards the taller trees in the eastLooking eastward from the site of the non-40 ssb station, the “long wire” tree is to the left, and the tree proposed as the other end of the dipole is on the right in the background. Closer, the trees on the right are the site for the 80/20 cw station, so the dipole would run in a straight line past the station, requiring a 50-100 foot feedline if we played it right with the ropes on each end.

In addition to these antennas, Byron has volunteers the use of his 20-meter Moxon, which has been used several previous times at Field Day. John K4US has also made available a 40 foot push-up mast. We’ll have to figure out how to best use all of this equipment tomorrow night.

Guess I should get some soda and chips for tomorrow night…

Chicago, Boxen, and Heil

A view out the window of the Marriott Courtyard downtown hotel. In the foreground: a tentec 1320, straight key, and Hendricks SLT+ longwire tuner
A view towards the lake

This week as the American Society of Clinical Oncology’s annual meeting in Chicago, and I spent five days just north of the river, at the Marriott on S. Ontario Street. When I arrived, I was quite excited to see that my 23rd floor window opened ever so slightly, meaning I could get an antenna out. For the next several days, though, I was busy around the clock, and only on the final day did I get a chance to try to operate from the hotel. As seems to be a trend with these hotel operations, it failed miserably.

The rig was the TenTec 1320, so I was looking at day time operation, but I had a slight problem – the side of the hotel was white and my antenna wire was black. I wasn’t so much worried about someone noticing my antenna from the street level, after all, 30 feet of black wire up about 200+ feet is pretty difficult to see, but I was worried about neighbors hearing something tapping at their window and then seeing the black, insulated wire dangling. One good pull, and various pieces of my station would be headed towards the pavement.

There is a Radio Shack on Michigan, just south of the river, and as Ben informed me, they are unusually competent. I walked in, asked for antenna wire, and they knew where it was!

When I got back to the room, I figured that since I was so high up, I might as well put up as long a wire as possible. I doubled the 31.5′ length recommended by the SLT+ tuner manual to make a full wave longwire. It would have been nice to have had a tape measure, but I was able to work it out in multiples of 8.5 and 11 inches, which was doable with what I had on hand. I weighted the far end down with a ring from a keychain. I ran the counterpoise wire along the floor of the hotel room, and yes, tripped over it several times.

I looked around for something to protect and insulate the wire as it passed through the window sash, and decided that one of the throw-away ASCO newspapers could be rolled into a tube, and would help get the wire a little bit away from the building.

Not far enough, though. Although I had two of the elements of the magical formula for antennas (lots of wire, high up), I think the wire’s proximity to the building killed it. I was able to tune the antenna to fully extinguish the LED on the SLT+ tuner, indicating a good match, but being near the metal structure of the building effectively shielded the antenna. I heard few cw conversations on 20m in the morning. Granted, it was a weekday, but even so, the signals were not loud. I tried calling CQ for a while, but no responses. Now that I’m back in Virginia, I’ll need to double check the radio to make sure it is transmitting correctly, but I’m pretty sure it was the antenna and not the radio.

two large cardboard boxes awaiting unpacking
Total weight: 50 kilos.

I got back late Tuesday night, and had two large boxes waiting for me when I walked in — the equipment that I had shipped out to Operation Sizzling Pork. Tymme had shipped it two days before. Score one for UPS Ground service (and Tymme’s professional-grade packing skillz).

Not really related to any of this travel, but still along the lines of amateur radio, on the way to work yesterday, I noticed that Bob Heil had produced three episodes of the “Ham Nation” podcast. I had enjoyed his interview with Leo Laporte on Triangulation a couple months ago, and I had heard in subsequent weeks that they would be working on a ham radio-specific show for the Twit network.

As much as I appreciate the effort, I can’t say that the first few shows have, pardon the expression, resonated with me. The show may need some time to find itself, but I think it needs more structure. I wonder if it wouldn’t work better to have two hosts, one of whom is not an expert and could ask the questions that might be occurring to the audience. The show also needs to figure out what audience it wants to address. The other shows on Twit presume a sophisticated audience with knowledge of the field (e.g., Security Now), but there is something of a proselytizing aspect to Ham Nation. There is a huge audience of people worldwide who are already hams, and these are the people who most likely have sought out the show (and, from a commercial aspect down the road, probably the best target audience for ham-related ads).

Two contests, one rock

A night time cartoon of a tent and camp fire
Camping

I could say that we selected Rocky Gap State Park (78.65061 W, 39.71315 N) for Memorial Day camping because I knew I would be running a rock-bound transceiver in a QRP contest, but the truth is that as usual we waited until the last minute to make camping reservations, and there weren’t many choices for state parks within a three hours drive of Washington, DC. Despite the  last minute preparations, the camping went off without a hitch (literally, since we shoved everything in the back of one car).

We left early on Saturday morning, had tents up by around noon, and I then spent some time entertaining the neighbors by throwing soda bottles with strings into the high trees. In appreciation, they turned up their country music, which was much appreciated, but not by me.

This was the CQ WW WPX CW contest weekend, so I knew there would be a ton of activity, with a good chance to be heard internationally. For that contest, I brought the TenTec 1320, and ran its ~ 5W into a longwire antenna through my Hendricks SLT+ antenna matcher. That rig only tunes 20m (~14.003 to 14.073), so I was limited to daylight plus a bit. With other camping activities going on, I periodically sampled the band to see what propagation paths were open. I was using a straight key as I don’t have my keyers on hand, but it wasn’t too bad since I wasn’t calling CQ much with such a peashooter station. Logging was performed in the classic style: paper and pen, with a lot of page flipping to avoid dupes.

The late afternoon/early evening both days was my best time. I logged 31 contacts, with DX to Aruba, Canada, France, Germany, Italy, Martinique, Spain, and Venezuela.

The CQ contest was over at 20:00 local time on Sunday, just in time for the ARCI Hoot Owl Sprint to begin. I had brought the 40m rockmite for this contest, since the contest offers bonuses both for QRPp operation and field operation. With the large membership of the ARCI potentially listening, I thought I might have a chance to be heard by someone.

I started at 20:00 EDT (00:00 Z) and stayed at it for 3 and a half hours, before I decided to walk down to the lake and stare at the clear night sky for a while. The rockmite has a built-in picokeyer, so I was able to use my Bencher BY-1 paddles, which was a good thing since I was somewhat zombified that late in the evening after a good night’s sleep on hard ground the night before.

A giant mosquito attacks a running man
Rumors may have exaggerated somewhat

Not only did I log some radio contacts, but I also was visited by many species of insects, who were attracted to the coleman lantern providing light for the log book. In fact, one unlucky bug is a permanent addition to the logbook itself.

In all, I logged nine contacts in six states (MI, NC, NJ, NY, OH, and VA). Five of these contacts were with ARCI members, who gave their member number in exchange, the rest sent me their power, some QRP, some not. I assume for the purposes of the contest in terms of my score, my power matters, but not theirs. Because I was operating on the rockmite at 500 mW output, my score got a 10x multiplier. Even more helpful, I got an additional 5000 points for operating portable (a bonus ~3x bigger than my score itself).

Operating with the Rockmite takes some patience, as the bandpass is large enough to hear many simultaneous conversations. When stations reply, it can be hard to tell if they are zero beat or not, particularly if they send just their call rather than “ai4sv de mycall mycall”.  Infrequently, I also had a touch of broadcast band interference, which faded in and out, and was always too tenuous to pick out specific spoken words.

Rocky Gap State Park was not chosen based on its potential as a contest location, but it worked well as one. The park elevation is about 1200 feet, and we were in site 182, which is at the far end of one loop, at the top of a hill, and surrounded by woods. Our site did not have electrical feeds, which further reduced the noise.  The entire site is in a valley, however, with taller hills to the east and west, so some low angle radiation may not have passed.

I would certainly consider Rocky Gap again for family camping, but I have my eye on some sites that are both closer and more elevated, for instance in West Viriginia, Black Water Falls (elevation 2897 feet) or Pipestem Resort (elevation 2690 feet, plus it has the word “Resort” in the name).

 

No QSOs in Boca Raton

This started as more of an IF (interactive fiction — not intermediate frequency) blog, but it does make a lot of sense to consolidate other topics here as well, since most of the time when I have to list a “blog” or “web site” link, I list this one. So, consider the flood gates opened. That probably means a flurry of excited posts followed by intermittent (on a geological time scale) dry spells. Let’s face it: that’s just how I am about updating websites. Maybe postings will be more regular if I can broaden the scope of the posts to just about everything and if the blog posts are useful to me as a sort of lab notebook.

Along these lines, one topic I’d like to document is ham radio trips, which I will conveniently define as any time I am not at home and get to play radio. Since I take a lot of trips for work, and since I almost always take a radio along, there should be a bunch of these.  Very often, the conditions aren’t optimal, and I don’t have a lot of time on trips, so more often that not, I probably won’t make that many contacts, but it’s more the effort than the QSO count.

Rather than recount projects and outings to date, I’ll just start from here forward. This weekend, I spent a couple days in Boca Raton. Scratch that. That’s how it is listed on the map — it is actually Deerfield Beach, Florida.  It’s only a beach if you consider concrete to be beach-like. It’s inland a few miles, and the view was of route 95. The conference I was attending was held at a resort that actually *is* in Boca Raton and overlooks the the ocean, but  I’m travelling at government rate, and that only goes so far.

My room was on the third floor of the hotel, right near the front entrance, which made antenna placement challenging.  On the first evening, I bid my time until there were no cabs or cars in the oval driveway, and then lobbed a 65′ long wire over a palm tree. I had attached it to a water bottle, and A long wire antenna running from the window to a palm treecouldn’t see where it landed after I gave it a toss. There were a couple tense moments when I went looking for it outside and found it dangling 20′ above the driveway, over the heads of some oblivious guests. I managed to yank it back a bit and get it into the bushes. Later that night, after dark, I guyed it down more substantially. Most of the antennas was elevated at about 35′, with the distant end down lower. I ran a 35′ counterpoise around the room and tuned the whole thing with a Hendricks SLT+ tuner.

The rig du jour was the 40m Rockmite, with the 7028.0/7028.9 crystal, running from a 7.2 Ah absorbed glass fiber lead acid battery. A picokeyer was built into the rockmite, and morse code was generated by a Palm Paddle which was duct taped to the battery. Where the wire crossed the metal window frame, I wrapped some duct tape around the wire as padding and then closed the window snuggly. Luckily, the hotel cleaning crew didn’t mind wires sticking out the window, and left the whole thing intact while I was attending my meeting on Saturday.

So far, I have had two — count them, two — contacts on the rockmite, but considering that it only puts out 300mW, that’s not too bad. Both have been from home using my 43′ vertical antenna (which is nothing more than a vertical wire radiator slung into a tree plus a few ground radials). One contact was across town, the other was to Michigan.  In the Michigan case, I was responding to a CQ call, and it was a difficult QSO.

I had no problem hearing other stations calling on 7.028 plus or minus 1 khz. Powerful stations would cut across both of my frequencies, and I had to wait them out. I heard strong signals from Italy, Slovakia, Slovenia, Germany, Croatia, France, and around sunset, from Columbia. Some strong local signals (SC, GA) were zero beat, but I could not work them. I called for a few hours intermittently, but had no responses. Well, maybe some qrz’s, but I am not sure to whom they were replying.

This was the first I had tried out the SLT tuner with the rockmite. Interestingly, the rockmite is powerful enough to illuminate the LED that tells you when the system is resonant. I would have wondered if my signal were getting out at all, if I had not had some confirmation from the reverse beacon network. Apparently, I was just above noise for a few of the stations, but at times, my signal was pretty decent (also, though, taking into considerations that the receiving systems for some of these reporting stations have high gain antennas).

So, no bites, not even nibbles, but considering that the antenna was somewhat of a compromise, I’m not writing off the rockmite. I am, however, strongly considering finishing the Texas Topper amplifier, which would boost the signal nearer to 5W and give me a fighting chance when my antenna options are limited.