Tag Archives: 2m Yagi

2el Vertical Beam Antenna WSPR Results

I ran the 2el vertical beam antenna on 20m WSPR for most of the last week. This time I looked at the WSPR challenge data as compared to N5CEY’s station about 15 miles away. During the week we both made the WSPR challenge scoreboard. On some days I had a higher unique count while on others N5CEY did. The WSPR Challenge site provides a list of all the stations heard in a 24 hour period along with their counts. This can be downloaded and sorted to see which stations had the highest counts. The data for a specific station can then be downloaded over the time period. Here is the count comparison:

wspr challenge counts

Here is a plot of the reported SNR vs time to K8JBV in Ohio from both my station (red) and N5CEY (blue):

WSPR comp

This chart is fairly typical and shows that N5CEY has about a 6dB higher SNR at his station vs. mine. I did note at least two stations, one in Georgia and the other in Florida, that had SNR roughly equal at the two receiving stations. This correlates well with the direction I have the vertical beam pointed. Likewise stations on the backside of the beam have a  few dB more separation.

I am pretty happy with the performance of the vertical beam antenna overall. What I would like to do next is operate portable from a more rural location and measure and differences in SNR on WSPR.


Built the 4 element 2m Yagi in Time for “Simplex Sunday”

The 4 element 2m Yagi build when pretty well this afternoon. Here it is up about 18ft on the painters pole:

Photo Aug 02, 5 14 49 PM

This is using an interesting 4:1 balun design using RG-6U coax. I can hit the local repeater quite well with it and am now waiting to try this out on “Simplex Sunday” the local VHF simplex net.

UPDATE: I’d say the Yagi was a fail. I can hit local repeater and local simplex but that was about it. It did seem very sensitive to direction as one would expect from a beam. Biggest evidence that something isn’t working right is that I could not hit the Harlingen or La Feria repeaters. More than likely it needs some tuning and unfortunately I don’t have an antenna analyzer that can deal with VHF. Further evidence that something is not quite right is that 2m Moxon is able to hit both those repeaters without any problems. It will be interesting to see how the Moxon performs on nights with good tropospheric ducting potential.

Next up a 2m 4 element Yagi

I broke down and started working on a 4 element Yagi for 2m. The gain predicted is about 5dB higher than what I had on the moxon albeit with half the beam width. I had enough #8 wire left over from the Moxon build to make this antenna. This afternoon I straightened and cut the wire and drilled holes in the positions on the PVC pipe I will use for a boom. Hope to finish this for tests on tomorrows local “Simplex Sunday”…