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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