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Yes. The antenna must always be considered as a whole here together with the feed line.
With the help of this Excel spreadsheet, it is easy to calculate double-Zepp antennas, which help to avoid the unfavourable voltage coupling.
Under radiator length you enter the length of an antenna limb from the feeding point to the
to the end insulator. Furthermore, the length of the feed line and its shortening factor must be entered.
In column C, the wire length of the entire system from the antenna coupler to the end insulator in LAMBDA can be read. Values around 0.5 - 1.0 - 1.5 - etc. mean voltage coupling and are unfavourable. Therefore the ranges 0.45 - 0.55 ; 0.95 -1.05; 1.45 - 1.55 should be avoided. These are also displayed in RED during a calculation. From approx. 1.5 lambda the stress maxima are clearly less pronounced and the calculations become increasingly inaccurate. The voltage maximum at 0.5 lambda is extreme and should in no case be in an amateur radio band that is also used.
If all numbers in column C are displayed in green, the values are favourable. If red numbers appear, the lengths should be changed until all numbers are green again.
Double-zepp antennas still work with good efficiency when the radiator is slightly shortened. The shortening should not be more than 1/3 of a half-wave dipole for the frequency in question. This means that one limb of a double-zepp-antenna, which should still have a good efficiency on 160m, should not be shorter than 40 x 0.66 = 26.66m.
73 Armin