Topband: Beverage current distribution

[Richard Karlquist (N6RK)]

Yesterday, I measured the current distribution on my
550 ft beverages.  The near end/far end current ratio
was 5 dB on 160m gradually increasing to 10 dB on 40m.
It seems to me that, at 550 ft, I have already reached
the point of diminishing returns on beverage length,
and that on 40/80 meters, I might very well want
to go down to 300 feet or so.  It didn't make any
significant difference when I changed the height from
2 feet to 5 feet.  Anyone have any thoughts on this?

BTW, these beverages were outstanding in the heavy
QRN yesterday.  They were even a big help working
Europe on 30m.  So, whatever the current distribution,
they hear well, at least.

(Experimental details:  I used one of those clamp-on
RFI cores for line cords that opens up like a clam
shell.  I put 5 turns on the secondary (the beverage
itself being a 1 turn primary).  Primary impedance
was about 3 ohms on 160m; should be negligible.
Besides both ends, I also checked at 1/4, 1/2 and 3/4
points on beverage, and current linearly tapered off
apparently no standing waves to speak off.)

richard@karlquist.com
www.karlquist.com