Suggest you go with a dipole of whatever length you can put up fed with ladder
line and use a good tuner with balun on all bands (if you can find a Z-match
with
air coil coupling, that's the best, next is a differential T-match and then the
conventional T-match tuners with built in baluns - all will work) . Traps are
fussy, lossy, have weather issues, etc., so why go to the trouble unless you
have
a good reason to? Adding ladder line to a trapped antenna seems to be asking
for
more hassle with entrance issues, etc. and probably forcing use of a tuner (not
a
bad thing, but it is another item to keep adjusted). The pattern questions are
dependent on height, surrounding objects, etc. - the old rule "as high as you
can" may still be a compromise.
Of course both types of antenna work - I use a flat-top fed with ladder line and
a tuner at the cottage for all bands 80-10 with about 160 DXCC in casual
operating. The other antenna on a small city lot (15.5 x 120 ft) is a trapped
80-40-30 fed with coax and a bead balun using the rig's internal tuner to smooth
out the rough edges (over 100 DXCC on 40m over the past two years). Operating
convenience, real estate, and feedline entrance issues made the difference as to
what to use where.
FYI - trap antennas are easy to build with a grid dipper, noise bridge or
analyzer. A few formulas out of the handbook with coils wound on PVC pipe forms
and some caps with high enough voltage rating from the next hamfest are all
that's needed.
GL 73, George VE3YV / K8HI
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