Diamond D-130N on 4 m
Published on 20 May 2012 by Marc PA1O
Some time ago I have investigated the frequency adjustment of my Diamond discone antenna with the results in the below picture.
Frequency [MHz]3550707580859095100105110
Length [mm]127082038031025721518516312210082

Standard there is a top rod with dimensions for 50 MHz operation, but it can easily be tuned up or down across a wide range.

There is a lot of D-130N discones around, and I think the information will be helpful for others who want to use this popular antenna on 4 m!

Diamond D-130 datasheet.