Hello!  I'm not sure who said it, but I have found copper pipe 1/2" rigid to 
be very suitable for building a dual-band j-pole.  Very simple to do and it 
has ears that hear lots of otherwise weak signals.
Sure is good to see the echo alive with discussion again!! :-)
I think I have an article on how you build the vertical out of coax.  Use a 
1/4 wavelength of coax X velocity factor and you alternate the connection of 
the center conductor and the shield.  Are we all confused yet??  Basically, 
one time the shield is soldered to the center conductor and the next section 
it is reversed. 
Lets figure out this one!!
73 de Stan
KC5BFA
--- GEcho/386 1.11+
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