The members of the Loop Antennas group may be interested to learn how I use Flag antennas (delta configuration) for receiving trans-Pacific medium waveMessage 1 of 1 , May 26, 2012View SourceThe members of the Loop Antennas group may be interested to learn how I use Flag antennas (delta configuration) for receiving trans-Pacific medium wave stations from the Washington State coast. This DXpedition took place at Grayland Beach State Park, Washington on May 7th through 9th.The month of May is not considered prime time for either DU (Down Under) or Asian medium wave from the Washington coast, so my "DXpectations" weren't very high for this trip. Besides the sub-par season, we're a few years removed from the periods of excellent medium wave DX heard during the low point in the last solar cycle. I had planned to be content with antenna experiments, figuring I may not hear any overseas DX worth logging.Surprise! The first night of the 7th (UTC) was indeed a bust, but the 8th and 9th progressively improved--all the way through local sunrise and my last recorded Perseus SDR files just past 1300 UTC.All loggings below were made with a single delta Flag antenna, oriented at 240 degrees. The high, dense brush in the southwest direction from my camp site prevented me from creating a phased array as I had planned, so I erected the 2nd loop at 310 degrees to hopefully be optimum for any Asian TPs. The two loops were identical except for their bearing (60 ft. base wire at 3 feet above ground, 22 ft. apex height, 1150 ohms termination resistor (modeled in EZNEC... thanks KAZ), and using the excellent "LN" (low noise) version of Wellbrook's FLG100 modules.This was the first time I've used single delta loops rather than arrays of two or four loops, and the directionality was better than I expected. Check out this audio clip which compares approx. 10 seconds each of daytime reception on 820 kHz, as I switch between antennas. One signal is KGNW Seattle and the other is KORC Waldport, OR. I have used FLG100 modules for years, but I'm enjoying DXing with the upgraded FLG100LNs now. They seem "transparent" in use with no detectable noise of their own.DX reception on the 8th was modest, but it was all Asian until sunrise approached when reception shifted mostly to Australia & New Zealand. Even during the hours well before sunrise, the Japanese, Chinese, and South Korean stations came in best on the southwest delta Flag... evidently a case of skewed path reception, perhaps due to the disturbed geo-conditions.The last night of the DXpedition on the 9th was almost entirely mid-band DU reception and most of the signals were logged during the last 1-1/2 hours before sunrise. I did note a few very weak Japanese signals and they were best on the northwest loop, as typical. The ability to "rewind" the entire medium wave band with Perseus WAV files was again the #1 tool for capturing as much DX as possible, especially when propagation is poor and interesting foreign signals are hard to find.A few photos with captions from the DXpedition can be seen in this folder: https://picasaweb. google.com/ 114798392023680237679/ GraylandDXpeditionMay792012 The folder includes photos of the FLG100LN delta Flag setup.The loggings from this DXpedition (MS Word file): http://www.mediafire.com/view/?k7k35x175bg2468 Of interest may be the audio clip of 2XD Southern Star, Napier, New Zealand (909 kHz) linked from the document. It's a good example of what a single loop can accomplish on a frequency one kHz away from a domestic 10 kHz North American signal. When two of these antennas are phased the splatter can often be reduced quite a bit. I plan to return to the state park in August, at a spot where I'll have room again for a phased array.
Guy Atkins KE7MAV
Puyallup, WA USA
DXing at Grayland Beach State Park, WA
Perseus SDR & AR7030 Plus (modded)
Wellbrook FLG100LN Delta Flags at 240 & 310 degrees