Sunday, November 6, 2011

Good Day for a "Beverage Hike"

After repairing the Monster-L a few days ago, I decided it was time to inspect/repair the Beverage antennas. Tim, K8RRT, strongly suggested I wait until a Sunday to avoid any confrontations with deer hunters so we decided to make our trek today. We loaded up with a 10-foot aluminum tube (two 5-foot pieces) with a wire hook on the top to lift the wire up over branches, small saw, pruning sheers, chain saw, tape, dacron line, split wire nuts, hand tools and fluids for us. As we hiked along the 60° / 240° Beverage (Reversible), we found some small branches over the Beverage and a couple of forearm size trees that we were able to lift by ourselves. At the beginning the Beverage wire was as tight as a Banjo string and would actually "sing" if you tapped it.

After about 650 feet we found the wire on the ground because 3 or 4 LARGE trees had fallen on it. Some of those were bigger around than me! No sense trying to cut those, so Tim went to the far end of this 900-foot long antenna and removed the wire which I then pulled from under the trees. We re-strung the wire over the dead-fall and now had the Beverage back to its original condition. It was amazing that the 2-conductor wire (WD-1A Military wire) had not broken, as tightly has it had been stretched.

On the way back down the ridge, we heard others in the woods! Tim and I stopped and listened and determined it was just some teenagers playing "Paint Ball." We were within 50 yards of them but I do not think they even knew we were there. Tim was armed with a small, pistol-sized shotgun and we wondered what the kids would do if we fired off a round but we decided to just silently drift away. On the way back to the Beverage Hub, we came back the route of the un-terminated North/South 500-foot antenna and found one or two arm-sized trees on it which we removed.

We completed this inspection/repair mission in less than 3 hours. One more Reversible Beverage remains to be inspected but because Tim had to go to work and I needed some "sit-down time", we elected to stop for today. After sundown, I did a quick "check" of the 60° Beverage to see if it was back being the "Killer" receive antenna it was last year. I've posted two small MP3 files below to show how it plays. Click on the callsign and the file will download or be played in your Browser or by using Windows Media Player or other MP3 player on your computer.

EA8DO - He sends "CQ EA8DO EA8DO" then a station starts to answer him. I was listening to him on the Beverage until he sent "EA" the second time and that's when I switched to the Transmit antenna. You hear him send "CQ EA8DO EA" and then he all but disappears in the noise as I switch to the transmit antenna.

S5ØA is in a QSO with N4NN and you can hear him sending "N N4NN TKS 73" and in the middle of the "3" I changed to the transmit antenna, then back to the Beverage then back and forth once more. It is pretty apparent when he is being received on the Beverage wouldn't you say?

I think our little project today was extremely beneficial. Tonight I can hear TU2T weakly, not strong enough to call, but strong enough to copy reports and portions of the stations he is working. Hopefully he will be on Top-Band near his sunrise as with a little enhancement, I think I can work him.

Saturday, November 5, 2011

WVU's Ms. Mountaineer for 2011

May I present West Virginia University's Ms. Mountaineer for 2011, Ms. Katlin Stinespring! Click on any photo to see a larger image.

Katlin is the eldest daughter of Tim Stinespring, K8RRT, and is a senior at West Virginia University. She was chosen today from five finalists all of whom are seniors at WVU.

Below is a description of this award:

The award recognizes students’ exemplary academic achievement and extracurricular involvement. All applicants must be eligible for graduation by May 2011 to be considered.

Here is Katlin's bio:

Katlin Stinespring, a public relations major, is a Hurricane native and is sponsored by the National Society of Collegiate Scholars. Stinespring is the assistant clarinet section leader and woodwind rank leader of the Mountaineer Marching Band and the vice president of public relations and membership of the National Society of Collegiate Scholars among other activities at WVU. She is the daughter of Tim and Pam Stinespring.

The entire West Virginia DX Association is over-joyed that Tim's daughter has achieved such success. As many have said, it is obviously a credit to her abilities and to the parenting she has received. Congratulations, Katlin, you really deserve this!

Thursday, November 3, 2011

K8RRT's Dual-Flag Receive Antenna

The photo at the left shows Tim, K8RRT, standing behind his new Dual-Flag receive antenna. The antenna is made up of two rectangles 30-feet long by 20-feet tall. The telephone pole is set up to accommodate a total of 3 or 4 Flags aimed in different directions. The feedpoint is at the bottom corner next to the far support. That support is made up of military surplus telescoping fiberglass tubes available on eBay. You can see a close-up of the feedpoint in the small photo on the right. Click on any photo to enlarge it then Close the open photo window or use your BACK button to return to this page. The photo of the antenna was adjusted so that the wires showed up a little better against the bright sky.

Below is a Posting by Charlie, N8RR, who has been leading the use of this type of antenna here locally. He gives a fuller description of the antenna.

Yesterday in about 4 or 5 hours W8TN, K8RRT and I built a dual flag receive antenna for the low bands in Tim's field. We continue to refine the process of building these. The next one will have a couple of minor changes to the construction method. It occupies about the same length as a 40-M dipole.

These are pretty effective RX antennas on 160, 80 and even 40 meters. For those without space for a significant beverage, they might be a solution. My 60-degree dual flag held it's own with a 450' NE beverage, and was a bit less noisy most of the time. These antennas can be built to a lot smaller dimensions than this one used, and will still have great directivity. The smaller the antenna, the less output signal it has, and the more pre-amplification that is needed in the receive chain. I would not hesitate to build a small version of this for limited space, as rx pre-amplification is not expensive or difficult to obtain.

The flag antenna has been around a while. Some have even built rotatable flags, which by necessity are a lot smaller than this one. This current design is from the work of others, and I deserve and take no credit for it.

Tim's antenna models to have maximum gain response at 25 degrees elevation, with a f/b ratio of nearly 30 dB. The beam width at -3 dB points is 107.3 degrees. What this means is that Tim's antenna, which is centered on 60 degrees azimuth, will cover from 6.35 degrees azimuth around to 113.65 degrees azimuth before the gain response falls off 3 dB from maximum.

Although the antenna max gain is at 25 degrees above the horizon, it has significant response at lower angles. The local power lines are behind this antenna. At 2 degrees Azimuth, the model shows over 34 dB front to back ratio, so the antenna should really do a good job of rejecting noise from the powerline.

Now for the real world testing. I am anxious to see how this antenna performs for Tim in the real world of DXing!

The horizontal wires are 30', the vertical wires are 20'. VI in the drawing is the matching transformer. The antenna is fed with RG6 TV cable coax.
The terminating resistor is 1222 ohms. The antenna is directional toward the terminating resistor, away from the feedpoint.

If someone wants to build one of these in less space, it can be done at reduced dimensions.

One can also build a single flag version of this. The beam width is broader, the signal output is higher, but the front to back ratio is poorer. I built one of these single flags last year and at times it was useful.

73 Charlie N8RR