"Denny" wrote in message
oups.com...


Try one; prove me wrong; I dare ya!

Regards,
JS



I don't see where the "inventor" of the DLM style antenna has violated
any laws of physics... He has simply found the sweet spot of mixed C &
L and short straight radiating sections along a shortened antenna to
pull it into resonance while maintaining a a flatter SWR curve...
With the helical lower section if that is how it is actually
functioning also acting as an auto transformer he simplifies the
matching of the feed point to coax...
Sevick proved that shortened antennas can work well...
If you look at the Fisher Island data for the DLM it shows that the
gain of the antenna improves considerably with top loading - a finding
we would definitely expect in a shortened monopole... Authors from
Sevick, to Cebik, to W8JK, to W8JI, have championed the benefits of
top hats for short antennas...

BTW, we have the oposite end of the spectrum in the distributed
capacity antenna with multiple caps along the length to redistribute
current peaks... So using capacitive reactance to redistribute
current along the antenna is well known and documented...

All in all, it sounds like a fun antenna, John... The guys really
ought to be looking at this as a method of trimming 160 and 80
verticals to a more manageable size while retaining some bandwidth and
having easy matching... If I didn't already have full size antenna
arrays for these bands I would be out there building one to see how it
performs...

I would hope that all those posting on the topic have read all the
URL's provided - and also noted the point that the antenna benefits
from being elevated and having elevated radials to work against , even
whilst mounted over the excellent ground plane of the Navy's test
range - a major piece of information......

denny / k8do


I agree, this is just nothing new. As you say Jerry Sevick has already been
thier and done that. Jery already has established that making a short
antenna is no big deal as long as you have a good ground system and a low
loss matching network How well Vincents antenna performed has more to do the
the excellent ground system used in the test than anything special about the
antenna..



Jimie