Towertalk
[Top] [All Lists]

[TowerTalk] 80 meter double extended zepp

To: towertalk@contesting.com
Subject: [TowerTalk] 80 meter double extended zepp
From: Thomas Rieff <kc0pyk@yahoo.com>
Date: Thu, 3 Jun 2004 15:54:46 -0700 (PDT)
List-post: <mailto:towertalk@contesting.com>
I recently built a 80 double extended zepp using the HamCalc configuration.I 
cut the lengths for 3.555 MHz. Hoping for a broader multiband performance with 
a tuner. The lengths are as follows...168.4 ft for each top leg and 38 ft of 
450 ohm ladder line for the matching section and then into a 1:1 current balun.
My question is should the swr be 1:1 for the design frequency, is it 
attainable, or are double extended zepps inherently a high swr antenna. It 
currently runs about 5:1 without the tuner and goes higher on the other bands.I 
have not done any trimming or adding to the antenna lenghs. The information 
says to trim the ladder line matching section for lowering the swr. Another 
source I found said that the ladder line matching section should be cut at 30 
ft. 
I see a couple of options; scrap the balun and coax and run ladder line 
directly to the tuner, start trimming the ladder line (what is a reasonable 
amount per test?), scrap the antenna entirely and put up something else. I 
recently built a 40 meter loop with 72 ohm matching section and it worked 
perfectly 1:1, at its design frequency. I have a fair amount of room to put up 
wire.
Your thoughts are appreciated.
Tom KC0PYK 
 


KC0PYK 
Thomas Rieff 
2059 Sundance Lane 
North Mankato, MN 56003

                
---------------------------------
Do you Yahoo!?
Friends.  Fun. Try the all-new Yahoo! Messenger
_______________________________________________

See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless Weather 
Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with any questions 
and ask for Sherman, W2FLA.

_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

<Prev in Thread] Current Thread [Next in Thread>