...... I had decided long ago that the only way I was going to be able to hear (and work) the weak European stations on 160m was to have myself a Beverage. A Beverage antenna that is.
After reading countless articles and watching a YouTube presentation video on Improving 160m and 80m Antenna Performance I finally decided on a Reversible Beverage On the Ground (RBOG). Essentially that would give me the benefit of two directions using the same space as one beverage as well as not needing to be as long nor elevated from the ground. The wire just lays right on the ground, sometimes over a small fallen tree, but otherwise on the ground. Of course this approach does come with an inherent reduction of gain and an increase in angle of reception, however a compromise was the path I chose.
As soon as I had the antenna setup and tuned to 160m I was amazed at the difference I noticed immediately when I flipped the power switch on the pre-amplifier and a Slovania station that I could otherwise not hear well enough to work was now coming in with a strong enough signal that I felt I could now work them. Now actually working them was a different story as I quickly rushed to tune the transmit side of the house (antenna tuner on the doublet and the amplifier) only to find the signal had died out. Solid state amps and tuners do have their advantages, but that is the way it goes sometimes.
No need to worry though as later in the evening after the sun had set I tuned in and worked a Romanian and German station that I otherwise would not have even heard to work before the Beverage. It was already paying off in spades and after going back out today (the day after installing the Beverage) and getting exact coordinates on the feed end as well as the 'terminated' end and plotting on Google Earth, I came to realize that I had only ran a 161 feeet of wire for the antenna. That being just inside the length that they recommend with a BOG (between 160 and 200 feet).
Suffice to say the addage often tossed around; "a short beverage is better than no Beverage at all", seems to be very true. Simply increasing the received signal by approximately 6db (One S-unit) and in turn decreasing the noise floor was the difference in me working Europe and prior to the antenna installation, not even knowing they were there.
Below are various photos of the installation. Yes, it could very well be altered to increase performance, and possibly at a later time I will do just that. Matter of fact, I think I will be experimenting with an additional ground rod placed about 500 feet out and splicing the wires and extending the existing Beverage in the hopes of grabbing the 10db gain listed above. Just depends on whether I think the additional 4db is worth the effort and materials.
The three photos below show GPS positions and distances of the terminating end, feed end, as well the distance from the doublet, my main transmit antenna (long yellow line). The red line represents a planned future RBOG to cover from NW to SE (Alaska). Bear in mind that the distance from the transmitting antenna is approximately 1/4 λ - which is far closer than most would recommend, however I do not seem to have a problem so far (the kenwood TS-590S has a dedicated RX RCA jack and switches the circuit open on transmit) and I am willng to risk it based on my unique sittuation (buildings sheilding path, height of transmit antenna, etc.. ). Generally the further the better for reason other than possible receiver overlaoad as well, such as the transmit antenna transfering noise to the beverage via coupling, re-radiating, etc..
Coax running on the ground, over fallen trees, etc.. over to the feed end of the RBOG. Next photos are of the 16/2 Lanscape Lighting Wire, and finally the far end conection. The ground rods are actually 8 foot long and leaving approximately 1.5 foot above ground will allow me to go back out and paint the upper portion of the rod with white or orange paint so that they are not likely to trip me up when out in the woods hunting or - well - running more antenna wires.
Any of the photos can be enlarged to full resolution using the expand icon in the top right portion of the popup window. ESC key will close the windows.
I will post audio files or videos at a later time to demonstrate how well a modest 160 foot BOG antenna will work.
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You will need to make an adjustment in the "FFT Display" section to the "Shift" parameter to match your offset. In my particular sittuation 140 Hz seems to me the magical number to allow the frequency to line up accurately in the waterfall.
Also you will need to uncheck the "Swap" in the same section as this was what was causing my frequency readout to be extremely innacurate.
See Photo Below
Other notes of interest:
1.) Depending upon your particular type of RTL-SDR Dongle, you will not have the option of using SDRSharp.R820T.dll in the drop down list. Instead I have found that if you use the RTL-SDR/USB for Q Sampling (HF Bands) and RTL-SDR/GUSB for the VHF/UHF and above bands with each set accordingly, you can just switch between the two different DLL's depending upon which spectrum you are targeting.
2.) The particular RTL-SDR Interface unit that I am using is a 100KHz-1.7GHz full band UV HF RTL-SDR USB Tuner Receiver/ R820T+8232 AM FM CW bought off ebay and, of course originating from Hong Kong, China. At the time it was $34.95 which included shipping and it took about 20 days for it to arrive (during the holiday season).
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in 1992 after receiving the novice ticket pictured to the left in the mailbox, the first contact that I had was on 10 meters CW with an Elmer of mine (N5CB - sk). The sunspot cycle at that time was declining however it was not uncommon for the band to be wide open at night and was nearly always open during the day. I had a Uniden HR-2510 - 10 meter rig in my truck at the time with a 150 - 200 watt amplifier feeding a 102" steel whip that I had cut to resonance. I was mainly active in the early mornings on my way to P.T. (U.S. Army) and after work on the ride home. 10 meters was a blast back then. I could routinely count on holding a QSO with many of the same stations every morning and evening on my short commute.
10 meter activity these days is a joke compared to its hayday of many previous sunspot cycles, yet from time to time the band will be open (for the lack of a better term) and you can still work a few DX contacts, but pretty much it is a band that I do not even waste my time on.
Knowing that the ARRL 10 meter Contest was coming up in December I decided I would give it a go with SSB only HP class, limited. I am now glad that I did. Although I am making no claims of great activity I was none the less very surprised that there was any activity at all. MN, WI, and IL contacts to my location were relentless. Other areas would open occasionally and afford access to about 30 of the 50 states for me and my modest setup as well as some South American, Mexico, and varios other locales.
I did spend a good amount of time (14 hrs) in operation and the payoff shoulf have been a little better as far as I am concerned but considering I am not a very good contestor to begin with, the resulting preliminary score 32,760 points was not too bad since I did not expect to work many stations at all. Instead I worked 364 +/- stations. That score paled in comparrison of some of the other SECC scores posted such as Jeff, W4DD, who would post results of 102,912 +/- points with 768 Q's in about the same amount of time. Guess that will really show the difffernce in a 5 ele yagi at 90' vs a HexBeam at 30' or so in height. Regardless I was proud of the performance of my HexBeam as I always am whether it be 20m, 17m, or even 10m. Anyone looking for a good 6 band HexBeam (20m - 6m) they could not do better than the one offered by K4HEX.com in my opinion.
I would say that there is always next year but chances are that the cycle will be at an even worse point and propogation will be essentially non existent. Then again, I could again be very surprised.
How To Calculate The Height Of A Tree Or Some Other Antenna Support Candidate
from Feburary 2014 QST magazine by Richard Fisher (KI6SN)
But How Do I Calculate Tree Height? Length is one challenge. Height, another. Here are four easy steps to calculate the height of any distant object.
• Find a stick that is equal in length to the distance from your cheekbone to your fingertips when your arm is fully extended in front of your face. Breaking a branch to proper length will work just fine. This isn’t rocket science.
• Hold the stick vertical by the tips of your thumb and index finger and put it in front of you with your arm fully extended and parallel to the ground.
• Walk toward or away from the tree until the top of the stick is visually lined up with the top of the tree and the bottom of the stick is lined up with the bottom of the tree. Visually, think of the stick eclipsing the tree — like the Moon covers the Sun in a solar eclipse.
• The distance from where you are standing to the base of the tree is equal to the height of the tree. Use a measuring tape if there’s one handy. If not, measure the approximate distance between your steps as you walk naturally. Count the number of steps you take to the base of the tree and multiply it by the number of feet and inches each of your steps cover.Write comment (1 Comment)