[UK-CONTEST] Antenna for SSB field day

[Dave Sergeant]

On 13 Aug 2010 at 14:07, Andy Summers wrote:

> Chris asked why you would want to use a fan dipole. I can't imagine a
> cheaper, simpler antenna. No ATU required! It also allows instant QSY.
> 

A fan dipole antenna to cover all 5 bands in SSB field day (or the 6 
bands in NFD) is far from a simple antenna. Loads of bits of wire to 
cut to length, and needing to be trimmed for each band because of their 
interactions, and lots of wire to get tangled up in the field. The lack 
of a need for an atu is less of an advantage these days with readily 
available auto atus. If you have one of those which remembers settings 
per band and allows you instant band change then by far the simplest 
antenna is a doublet fed with open wire feeder or 300 ohm ribbon for 
lower powers, and a transformer balun.

The only disadvantage with a doublet is that it needs to be long enough 
for the lowest band you are using, which means it is far from optimum 
for the highest band. That would be where a trapped dipole would come 
in.

When we did NFD a few years ago (sadly no longer due to lack of 
operators) we always used a doublet. I used one in the low power 
contest last month, simple inverted V with 90ft total length. Matched 
with the K2 internal tuner. Quick to put up single handed and put me 
3rd place in the 3W /P section under attrocious conditions.

73 Dave G3YMC

http://www.davesergeant.com