Question about radiation pattern of an 11m inverted V dipole

[daronj]

I am very new to the radio hobby and I'm interested in DX communication. I just purchased a President Mckinley SSB radio (all stock) and built a 1/2 wave inverted-V dipole, mounted in my attic. I am in Louisiana and the legs of the dipole are pointed NNE and SSW. My understanding is that the radiation pattern is perpendicular to the direction of the legs, so this should cover the western United States. Surprisingly enough, I have made a number of LSB contacts with this antenna and stock radio, with good audio reports, from 900 to 1200 miles away. The thing I don't quite understand is that ALL of my contacts have been in the north-north east around Pennsylvania, New York, etc. Directly in line with the legs of the dipole. I haven't reached anyone west of my location, even though I can hear them very well.

Is there a particular reason I am seeing this performance from my antenna?

Thanks,
Daron

 

[K7MEM]

A common dipole has major lobes perpendicular to the dipole wire (dipole legs). These lobes are rather ill defined. However, when you bring the end down, to form the Inverted-V, the antenna becomes omnidirectional. Which, for 11 Meters, is what you want. Also, if you are stuffing your antenna into your attic, it is unknown what the actual radiation patter is. You have house wiring, insulation backing, and other metallic objects that could skew your results.

Your antenna should really be out in the open, but I know that that isn't always possible. For 10 meters, I use a old Radio Shack vertical dipole that is 18' in length. I modified the feed point with a open stub to move the input impedance from 11 Meters to 10 Meters.

The best thing you can do for making contacts, is get on when the propagation conditions are good. We are currently in Solar Cycle 25. It is predicted to peak about 33 months from now, in 2025. So enjoy it while you can because it will go away. 11 Meters is much like 10 Meters in that, it is a daylight band. Once the sun goes down propagation disappears. Do a google search on "11 meter propagation" for more information on what to expect of your signal. During a previous Solar Cycle, I found that my best time was about 2 hours before sundown.

One of the tools that I use to check propagation is the NA5B WebSDR system located in Washington. Right now, at 10:45 PM I can hear only one station from Georgia (CH19) making noise. Tune in early in the evening to check for activity.

 

[prcguy]

Yup mostly omni directional but favoring perpendicular to the wires. Since its inverted it will not be absolute horizontal or vertical but slant polarization and when talking to a local horizontal or vertical antenna you will have a little loss compared to matching their pol on the order of 1 to 3dB average. For skip it wont matter.

Your current contacts are probably due more to skip conditions than antenna orientation.

 

[daronj]

Thanks for the information guys. I have noticed that during the morning hours beginning at about 9am, the radio really lights and lasts a good part of the day. then dead at night. I retired a couple of months ago so I have been spending, well, a lot of time listening and calling out during the day along with reading and researching. It's been quite entertaining.

Interesting info about the solar cycles. I guess I picked a good time to take up the hobby. I will say this, when I started tinkering with this stuff a month or so ago, I had no idea how deep the rabbit hole went It's very addictive and there is quite a lot to learn.

Thanks again!
Daron

 

[K7MEM]

It's very addictive and there is quite a lot to learn.

Then you might want to consider Amateur Radio. It would expand your scope to multiple bands of operation, different modes, and contacts all over the world. I have been a ham for almost 60 years. So, yes, it can be quite addictive. Information on getting licensed is readily available, like this on Getting Licensed. Just put "how to become a ham" in a google search. There is lots of information and videos. It's a lot easier to get licensed now than it was in the past.

 

[daronj]

Then you might want to consider Amateur Radio. It would expand your scope to multiple bands of operation, different modes, and contacts all over the world. I have been a ham for almost 60 years. So, yes, it can be quite addictive. Information on getting licensed is readily available, like this on Getting Licensed. Just put "how to become a ham" in a google search. There is lots of information and videos. It's a lot easier to get licensed now than it was in the past.

I am already considering that as well. Quick question about that. Do the Ham bands also depend on solar cycles for propagation like 11 meter?

 

[R0am3r]

I am already considering that as well. Quick question about that. Do the Ham bands also depend on solar cycles for propagation like 11 meter?

@daronj - Welcome to RadioReference! The higher frequency bands 15, 12, and 10 meters are very much dependent on the solar cycle for propagation. You will notice the 12 and 10 meter bands behave much like 11 meters and are often dead during the bottom of the solar cycles. Other bands offer propagation throughout the entire 11 year cycle. The great thing about the amateur radio bands is they are all unique.

The 10 meter band was open (for the east coast) to Europe and Africa this morning at 7am EST.