Topband: Beverage up but maybe has problems comments requested

wa3mej at comcast.net wa3mej at comcast.net
Fri Dec 2 19:31:42 PST 2011



OK    the Beverage is up, transformers installed, and coax hooked up. Let me refresh everyone’ memory   -   I put up a 490 ft window line beverage which turns out to be headed 30deg magnetic (best I could do on short notice) and it has a termination transformer as opposed to the open/short termination.   



  

  I have noticed several things: 

    1. I am not impressed with the front to back. I don’t think it is all it should be but I have not measured it. 
    2. Although I did work YN2CC last night I have not heard but one station from Europe . 
    3. There appears to be some discrimination off the side of the antenna. The 8’s, 9’s etc are down as much as 20db. 





  

Having said all of this I started rereading all of the literature and think I may have discovered a problem with my transformers.   I noticed that some calculated the transformers based directly on the impedance of the line/ surge z.   By this I mean they calculated the transformer turns based directly on say 50 ohms for the primary and   450 ohms for the secondary. 



  

When I designed my transformers I used the rule of 4 like is done with broad band transformers so that the turns would be calculated on 200 ohms for the primary and 1800 ohms for the secondary.    DID I ERR??????   This might be why there is no front to back like there should be and maybe even the why I can’t seem to hear the Europeans. 



  

Luckily changing the transformers is an easy task. 



  

Comments please ! 



  

Jim WA3MEJ 









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