Location
I set up my inverted vee antenna in the Rideau Falls park, next to the grounds of the Canada and the World Pavillion, parallel to Sussex drive, part of the Confederation Boulevard. The satellite image below doesn't actually show the Canada and the World Pavillion, because it is an old image.
Satellite View (Click on picture for full size image)
You can see the location on google maps by clicking here or by saving this file and opening it in google earth.
Note: You're probably wondering why I chose to orient my dipole parallel to Sussex drive (labelled Regional Road 93 in the picture above) which runs South-West to North-East. Well, it was a mistake! I had thought that Sussex ran South-East to North-West and therefore my maximum gain would be pointing South-West to North-East (South-West for the majority of U.S. states).
Station
The station was an Elecraft KX1, with optional 30m module and KXAT1 internal tuner, powered by 6 energizer lithium batteries, producing 2 Watts. I used Sony Fontopia earbuds and the Elecraft KXPD1 paddles, for a total station weight of:
| 0.9lbs |
|---|
... including the internal tuner & 30m board. I also had along a camp light and a notepad and pen, plus my Yaesu FT-51R handheld to monitor the local repeaters. In fact I had a chat with Verner, VE3WSZ, before the contest got underway.
Antenna
The antenna was a 20m full wave or 40m half wave (64 feet) inverted vee dipole made from #26AWG teflon coated wire and fed in the center (32 feet) with 22 feet of Radio Shack 300 ohm TV twinlead. The apex of the antenna was at 18 feet, attached to a Shakespeare Wonderpole TPS-20 20ft fishing pole which was held vertical by a four foot length of PVC pipe with 3 steel rods attached to the outside by jubilee clips, and sunk into the ground. The ends of the dipole were supported at 6 feet above the ground by fiberglass driveway markers.
The EZNEC model for this antenna is here.
Looking at the 20m azimuth and elevation plots, this antenna produces maximum useful gain broadside to the dipole, from ~4dBi gain at a 30 degree elevation, through ~6dBi gain at 60 degrees to ~7dBi gain at 90 degrees elevation. There is a ~3dBi gain difference in the 60 degree azimuth plot for the broadside direction compared to off the end of the antenna.
The 40m pattern is also shown on the plots. There is less gain on 40m (~2dBi at 30 degrees, ~3dBi at 60 degrees and ~4dBi at 90 degrees) and the gain lobes have flattened out more in the azimuth plot compared to 20m, there is only about 1dBi difference. This is because I had the apex of the antenna mounted well below a quarter wave at 40m.
20m Azimuth & Elevation Plots
What does that mean? Well there are no deep nulls in either the azimuth or elevation far field plots, so I can expect noise from thunderstorm activity to be strong regardless of where it is in Continental North America! Signals should be weaker on 40m compared to 20m. On 20m, signals from the North-West should be stronger than those from the South-West. This was a bad mistake on my part orienting the antenna in the wrong direction, and I reckon it lost me a good deal of 20m contest points (see later comments).
The modelled impedance at the feed point:
SWR Sweep
...indicates that the antenna is almost resonant on 40m, 30m, 15m and 10m, and should be easily matched to 20m. In practice I actually found that I could achieve a 1.0:1 match on 20m and 40m, but only 2.1:1 on 30m, but there were buildings and trees nearby which probably affected the SWR.
Log
I started listening in to 20m. There were a lot of stations present but signal strengths were really low! Most stations were R1/R2, S1/S2 with me. Suddenly I heard VA6RF really strong, he was in search & pounce mode working stations in the US. At this point I was confused. Remember I thought my gain lobe was going South-West. This was the opposite situation, Alberta was coming in clear as a bell while the mid-states were very weak. I found out why when I got home and looked at a map!
Contest Contacts & Radiation Pattern (Click on picture for full size image)
Anyway, after awhile, VA6RF started calling CQ so I came back to him and got a 559 report from Alberta. Shortly thereafter I heard NG7Z calling CQ so again I came back and got another 559. Now I was sure that I had oriented the antenna wrong; Washington State should have been in the low gain part of my radiation pattern and I couldn't hear TX, AZ, etc. at all! I stayed on 20m until about 0145, sending a few CQs myself and trying to work one or two of the weak mid-states but I was unable to bag any more contacts, so I moved to 40m.
| Call | Time | Freq (MHz) | SPC | RST | km | |
|---|---|---|---|---|---|---|
| VA6RF | 0120 | 14.060 | AB | 559 | 2760 | |
| NG7Z | 0122 | 20m | WA | 559 | 3513 | |
| K0XI | 0150 | 7.042 | MO | 599 | 1680 | |
| WA7LNW | 0215 | 7.039 | UT | 559 | 3220 | |
| VE3AXL | 0229 | 7.041 | ON | 559 | 1098 | |
| VE3XT | 0251 | 7.040 | ON | 559 | 1085 | |
40m was terrible! I had S8 interference from thunderstorms. It sounded like most of Continental North America was experiencing lightning on Monday night! Serves me right for using such an omnidirectional antenna! Well I tuned the filter down to 500Hz and started tuning in sweeps up from 7.037 to 7.043.
I heard the Russian spy station down on 7.038MHz sending 'D... D... D...', it is becoming a constant companion of the 40m QRP contests. I was able to work K0XI after about 5 minutes of trying. I need to check my receiver alignment, a couple of stations tonight weren't hearing me when I zero-beat them, but if I tuned up about 300Hz then I got a response. I saw that K0XI is a club, so I wonder what club member was OP that night!
It was another 25 minutes before I was able to work another station! I returned about 5 different stations calls, both zero-beat, and up/down ~300kHz, but no one was able to hear me, I think the QRN was pretty bad! Finally WA7LNW came back to me - he had a really strong signal here in ON, and he gave me 559.
I closed the contest by alternating between search & pounce, and calling CQ. Both VE3AXL and VE3XT came back to my CQ calls, and we exchanged 559s.
Version: 1.0 (October 5, 2005)
