My Experience with Beverages on 40 Meters
Gary Breed, K9AY
In 2001, I entered both the ARRL DX CW contest and CQWW DX CW contest in the Single-Operator Single-Band 40 M category (High Power). I managed to finish #4 US/VE in the ARRL contest, and in the CQWW, my score is #3 among the claimed scores that have been reported.
I am quite pleased with these results, because I do NOT have a 40M super-station! I have two 10-year-old ICOM 765 transceivers and an Alpha 99 amplifier. My main antenna on this band is a homebrew 2-element Yagi that is only 75 feet up. No, I'm not located on a mountaintop, either.
Why was I successful with a modest contest station? Simple--I used three Beverages to help me hear better. That's right--hearing better is an absolute necessity, even when you are running 1.5 kW. You need to hear the other station in the QRM of a pileup; you need to hear weak stations calling you when you are running; you need to focus on the stations you want to work even when running stations with strong signals..
I'm not going to suggest that Beverages will help a "big gun" station with stacked 4-element beams on a 200-foot tower--but for a medium-sized station like mine, they are highly effective.
My 40M Beverages
45 degrees (to Europe): 350-foot Beverage, 4 to 8 feet high.
310 degrees (to the Far East and parts of Oceania): 300-foot Beverage 6-feet high.
250 degrees (Oceania and some Central America): 225-foot Beverage 4-feet high.
All of these receiving antennas were terminated with a 4-foot ground rod and a 270-ohm 2-watt carbon resistor. The termination value was chosen by trial-and-error, and although 270 ohms is a lower value than usual, it is what seemed to work the best.
There is nothing special about these Beverages. They are made with #17 aluminum electric fence wire. It's cheap and light wire, and I put up my receiving antennas on a seasonal basis-they are removed in the Spring and replaced in the Fall (two of them cross parts of the yard that are in use when it isn't cold).
How do I know they work?
When running, I often used both radios in a dual-receive mode, one radio in each ear. When running Europeans, I would be listening with the beam in my right ear and the 350-foot Beverage in my left ear. While a few signals were more readable on the beam, the vast majority were heard much more clearly on the Beverage.
On long path signals around sunrise, the 250-degree Beverage was far superior to the beam. At sunrise after the first night of the CQWW contest, there was a short 30-minute opening to the Far East and UA9/0 that was skewed to the Southwest. Without the Beverages, I would have had much less success working stations at that time.
Here's the commercial!
AY Technologies' 9:1 TRX-9 matching transformer has excellent performance at 7 MHz (actually, it has low loss and accurate impedance transformation at all HF frequencies). Some "cookbook" transformers developed for 80 and 160 meters have too much inductance and stray capacitance for higher-frequency operation. Others work fine, but with the TRX-9 (or the 16:1 TRX-16), you know that 40M performance will be every bit as good as it is on 160 and 80.
I did not need a preamplifier with my Beverages, since the preamp in the IC765 is fairly "hot." If you decide to use preamp on 40, the Model PRE-2 provides 12 dB gain, and it includes a filter to reduce AM broadcast interference and shortwave interference above 8 MHz.
The Bottom Line
If you want to be more successful on 40M--whether DXing, contesting, operating QRP or just ragchewing--Beverages may help you hear better. And hearing is always half of any QSO!
AY Technologies * antennas
by K9AY * www.aytechnologies.com