Ivy,  I think the number of extra 5/8 or really 1/2 wavelength sections that 
you add is only limited by the strength of the material you are using.  Yes, 
each would add about 3 dB of signal strength, minus some small losses.
Have you considered one continous raditor that is made up of odd multiples of 
a 1/4 wave?  I understand that when you keep them odd, you don't have any 
problem with matching and such.  I'll build one today that's about 12 feet 
tall and check it with the analyzer and report back to you.
Isn't this FUN!!
73 de Stan 
KC5BFA
--- GEcho/386 1.11+
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