[ADXA] Pennant Antenna for RX

[rcurt at centurytel.net]

After making an attempt to operate on 160 where the noise was never below s7 and mostly over s9,  I realized I was fighting a losing battling unless I could figure out how to RX below my current noise floor.  At the recommendation of my friend Sid K3SX, I decided to try a pennant antenna, which I constructed earlier this week. I had already ordered 910 ohm terminating resistors a few days earlier,  and had a couple of binocular toroid cores that Mike (KB5WBH) had shared with me sometime back.  


I first constructed the transformer and tested it into a 200 ohm resistor on the bench. I found I needed to remove a couple turns for a near perfect match to 50 ohms. (This was a mistake).  I constructed the antenna out of 70 fet of #16 copper wire, using a fiberglass mast for support of the 14' vertical wire on the front end.  Upon hanging it temporarily in the front yard, pointing NW, I found the VSWR was near a 3:1 with a resistance of around 15 ohms. I then pulled the transformer off, and reconstructed it to the original specs of 3 turns on the primary and 12 turns on the secondary. This allowed a perfect match to 50 ohms on 160-40 meters. According to W8JI Tom Rauch, 11 turns on the secondary will match to a 75 ohm feed. 




Testing using pskreports stats was a roller coaster of thinking this is good,then swinging to I don't know if it is so good. Mike KB5WBH agreed to leave his transceiver on and I set one of my transceivers up on the inverted L using call sign W5ZJ/5, and the other transceiver up on the pennant, using W5ZJ. Using the RX stats from pskreporter on 3 stations was interesting, but inconclusive. I then decided that the only way to really tell was on the air, in real time.  




After reaiming the pennant from NW to NE , into Europe, Thursday evening, I found the pennant was nearly always + or - 6db  better in its favored direction, than the Inverted L, or 80 meter ladder line fed loop at 50 feet.  The pennant with the ft991a internal RX amp on has 5 s-units lower noise floor, than the Inverted L, and 4  s-units lower noise than the loop. I was able to receive European ft8 stations, that were non-existent on the inverted L and loop.


In the process of testing, I found the pennant to be even better on 40 and 80, than 160. I tuned to 3937 where some local stations meet in the mornings, and found the pennant made the receive almost FM like, by dropping out the background noise I have all time. On 40 meters, my noise is less, but the pennant still perfoms very well. 


Coincidentally, I found the pennant was completed just in time for the 160 meter contest this weekend. While being tied up part of the time, I hope to see if I can find some CW DX, and see how it performs there 


Attached are a couple of pictures, and a pdf file from DX engineering with information about the pennant where they state that 2 of these antennas together would equal a 1000' beverage. Is this possible? Yes, I am rolling this around in my mind, and think I would like to try and see. Now where did I put that other fibergalss mast, and where can I find the cheapest price on a roll of rg6? 


Have a great day and good luck in the contest this weekend. 


Randy/W5ZJ
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