Topband: How to measure the resonance of a tower?

DM4iM hamradio at
Tue Jan 18 05:10:38 PST 2011

thanks for all the input.

Today i installed a shunt wire, a box with a vacuum C and the coax to 
the shack. I have 12 radials so far, none of them is long enough, but 
that is the best i can do for now.
I got an immediate success, after a bit tweaking the C the antenna 
analyser showed a perfect and sharp swr after i lowered my 1/2 wave 
dipole and disconnected it from the tuner.
Then i realised that i had forgotten to connect the base/ground of the 
tower to the radials/shield of coax.

When connected, the analyser showed a much flater swr-curve and a 
minimum swr abt. 1.9:1

Should i be happy? Will this improve with more radials?
Should i ommit the connection to the base of the tower? How will this 


Martin DM4iM

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