[Elecraft] [K3] KAT3 and 160 with 40m long doublet

[David Cutter]

I used a low and bent doublet of 2 x 88ft per section for a while and it 
"tuned" up amazingly well on all bands 160 to 10 with the KAT3.  As a rule I 
like to use multi-band doublets away from any obvious in-band resonances, so 
that it doesn't experience very high Z anywhere, so, adding a bit on each 
end and stringing them wherever they will sensibly go should work for you. 
A choke in the coax feed is good.

David
G3UNA

I have only just recently added the KAT3 and I'm very impressed with it, but
given the praise heaped upon it by others I'm slightly surprised that the
best VSWR I can get on 160m is about 8:1.  The antenna is approximately a
doublet which is a half wave long on 80m ­ I say 'approximately' as it's
slightly off-centre fed.  I have about 7m of 300 ohm slotted down from the
feedpoint and then into a coaxial choke at roof level for the remaining 10m
into the back of the K3.  Substituting the straight connection for a 4:1
balun (Guanella) at the transition between the slotted feeder and the coax
helps slightly but not by much.

Tomorrow I may well add some extra wire to hang vertically down from the
ends of the doublet.  In the meantime I would be pleased to hear any
comments.

Happy New Year!

73 Stephen, G4SJP