HF antennas on short masts

[DK3IT]

Hi, regarding carbon fiber masts:

We discussed this here:

Telescopic poles - what do you use?

Martin, I think the carbon pole will work fine with your loaded vertical, but the resonant length is likely to change. A few years back I did many activations with a 7m carbon pole supporting a vertical wire into an antenna tuner and it seemed to work fine. Barry N1EU

I see the theoretical point, but we will have to check how much of an effect that is in practice. In a couple of weeks, I should have two identical sets of 5 and 6 m masts in glass-fiber and carbon fiber and could make a comparison.

Regarding Pedro’s question: The main difference between the old GfK rods and the new carbon-fiber masts from Decathlon seems to be that the latter ones weigh about 50 % of the former an, more importantly for me, are much shorter for transport. 40cm is really neat in a rucksack or carry-on luggage. 57 cm is already borderline even in a trolly, and will stick out of many small and medium-sized packpacks.

As for Ed’s comment: Yes, I guess a dipole cannot be mounted at the top segment, but keep in mind that:

1. The carbon-fiber version has many more segments (i guess 11 instead of 6 or so), so just taking the second thinnest will mean a reduction of only 40 cm or so.
2. The 6m version is lighter and shorter than the 5m Gfk versions from DECATHLON and lamdahalbe, so I guess it will be a net gain even if you have to go down a foot or two.
3. I am now often using verticals, and those have a minimal load on the tip if you add a rubber band or something similar a meter or so below the tip so that the full weight of the wire is not hanging on the tip.

Martin