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Inverted-L (was OT: Vertical antenna)

Posted by ARDUJENSKI on Dec 20, 2010; 3:45pm
URL: http://elecraft.85.s1.nabble.com/Inverted-L-was-OT-Vertical-antenna-tp5852957.html

Going from loop to vertical involves two very different lob patterns. It  
was never mentioned if the antenna performance was to favor local or DX. Here
is  one which it does not matter as it adapts for both.
 
A nice compromise antenna which takes into account:
---high and low angle lobe patterns
---good match (resonant on 80m)
---small footprint
 
======DESCRIPTION===============================


 
 INVERTED-L: 33 ft vertical, 33 ft top wire, feed at base against 12 16ft  
 radials. I use Radio Shack low loss 300 ohm tv wire for feed
 
 According to calculations EZNEC had a 40ft top wire. In the field I
trimmed it until we got an  
 acceptable match on several bands
 
 For supports I have used the DK9SQ mast as the main and used the Black
Widow  20ft
 for the end support with great success
 ----------------------------------------------------
 I use RCA connectors for many of my antennas. I install male RCAs on wires
 
 and interconnect with using DOUBLE FEMALES. For 300 ohm TV wire I will
solder  
 short piece of speaker wire to each of the conductors and then securely
tape
 the  soldered area to the ribbon insulator body . To the end of each
speaker
 wire I  afix a MALE RCA. Generally I will make one speaker wire on each
end a
 little  shorter (3/4 inch) so I can tell easily identify which wire is
which.
 The RCAs  work great and it they break off in the field I carry wire nuts
for  
 emergencies
 ----------------------------------------------------
 I have EZNEC pattern (PDF) for several bands and also a sketch for the  
300
 ohm connection if you want more details
 ----------------------------------------------------
 Note at the QTH I have used this for 80 and 160m with good success  
including
 contacts with Japan on 160m. I am sure the key is the other fellows  has
HUGE
 arrays but it worked.
 
 Hope this helps
 
 Alan KB7MBI
 



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