Topband: WD-1A 2-way Beverage

[Lee K7TJR]

Thanks Andrey you have confirmed my suspicions but.

>And RF signals from Back direction of
reception is not "injected" at feed point, so direct multiplication of
attenuation by length does not play here.


    It seems to me that All the signals from the back ( two transformer receiver end) direction come from 
the reflection transformer and therefore travel the full length of the transmission line so I believe that 
direct multiplication of the attenuation would be appropriate. If the signals are down 6 dB in 300 feet would
 not they be down 12dB in 600 feet? Signals from the front (reflection transformer end)) however do not 
use the transmission line except as a termination resistor. Perhaps because of reality versus theory in
 actual practice you only see 9 dB, I dont know? Wonder what it is on 80 meters?
 Am I missing something here? Perhaps you meant RF signals from the front, signals from the direction
 of the reflection transformer end which would be true. 
     I know that Beverages with this wire work OK and are useful for many, however at my location I have
 a Bidirectional (1Kft) with the reverse direction toward JA. It is made from aluminum fence wire with fairly low loss. 
At times here in the early a.m. this antenna drops clear into the noise floor of the receiver and its low noise
 preamp. I have verified this with other types of antennas. It is so quiet in that direction (over the Cascade 
mountain range and then Pacific ocean) that I often hear the Hyperfix low power navigation system in the
 Bering sea UA0 area. So my thoughts are to use caution if you are attempting a low noise direction with a
 longer antenna of this material as it depends on the noise floor of the QTH as you have pointed out. 
    You may never know just how quiet your QTH is if you dont try something better.  It seems to me you cannot
 verify that your antenna is above the noise floor just by connecting it to the RX with all the losses involved. 
     What ever way you look at it there is a lot of loss in the reverse direction! About 2 dB per100 feet as I see it.
 I still wonder about the incorrect termination effects due to losses and its affect on the RDF/pattern.
      It seems to me we all wait for that magic moment when it gets really quiet and we hear the one DX call we never
 thought we would hear. To me, I dont want to give away 5 to 10 or more dB of my system noise figure when I dont
 have to because I wait for that very magic moment every day!  YMMV

Lee K7TJR Oregon