On 1/5/2011 10:58 AM, Rick - NJ0IP / DJ0IP wrote:
Jerry, let me throw two things at you:
1. I think a horizontal loop is a pretty good radiator, straight up.
And those who like them find they work well for operations like SS and
FD where working stations in surrounding states on 80 and 40 is good.
One I used at a club FD was not small and worked well. One I put up in
my back yard for working a 400 mile path on 75 meters worked poorly for
that path.
2. The vertical dipole antenna I've described has been in use here for
nearly 20 years, at 3 different home QTH's and countless portable
operations. On 80m where one would think it is too short to work, I found
that I was always just as loud working stateside, JA, or VK, etc. on the
short vertical dipole, as I was on my full size horizontal dipole which was
only 40 ft. up. Nobody on this earth can convince me I'm wrong because I
have a logbook full of QSOs to prove it. (don't forget, I was in Germany)
It takes a good tuner to tune such a short antenna and even then its
hard to get a lot of current in the radiator and its the current that
radiates. It would be more effective on 80 with capacity hats and end
loading coils to increase the current in the radiating portion. But it
still radiates better than the incandescent lamp dummy load that has
been responsible for more than a few contacts on 10 or 15 meters over
the decades.
So, if someone tells me they can't get on 80m because they have no room, I
just say humbug!
You can get a good fiberglass pole, 40 ft long, for about $120 from
companies like Spiderbeam.
You can get 100 ft. of openwire (300 ohm or 450 ohm) for probably $35.
Add 40 ft. of copper wire and you have a good 80m antenna (well 80 thru 10m
antenna).
Its a little long for 10 and 15 meters, the signal at low angles is
attenuated seriously, but for sporadic E higher angle radiation is often
better.
While living in Oklahoma (until last week), I used a bigger version.
Using a 60 ft. Spiderbeam pole, I built my vertical dipole with 30' per
side.
On 80m in CQWW CW with about 800w, I was able to work every dx station that
came up on the DX cluster, be it in Africa, or anywhere else, with just one
or two calls.
As I said, people highly underestimate how well these antennas work.
L.B. Cebik W4RNL (SK) didn't. He too was a fan of the vertical dipole.
Actually, the main reason it works so well is because most people use
antennas on 80m which are worse! Hi
I agree, you should have good success with a vertical mounted on the metal
building.
I've always wanted to try that but never had the building.
I bought an antenna for that purpose right after I built a metal
building on ground I planned to build a house on in 1989. I've not yet
built that house, never will, but I built a second machine shed so I
could convert the first to house, but a proposed mall next door and the
fact that I never succeeded in totally weather proofing the metal
building and I got lazy with age so that didn't happen. In 2009 I bought
a house further out in the country with the latest Morton metal building
and for 13 months I concentrated on moving out. Now I'm moving in and
thinking much more about antennas. I have some on tripods on the roof
(tripods were already there) for VHF/UHF and last night I strung a wire
inside the house for receiving. Copied Europe on 75 very late at night
when the furnace was off. Have a furnace RFI problem to cure now.
73
Rick
The only problem with the antenna on the shed roof is that a feed line
to the house will be 150 feet long, though I could set up an operating
position in my camper that's stored inside and equipped as a mobile ham
station already. Or I could shove the debris aside and build a dedicated
ham shack in a corner. And put up the VHF/UHF/microwave tower along side
for short feed lines. Maybe I should put the ham shack up in the roof
area to shorten feed lines even more. Or go with an Omni VII and an
ethernet controller for the rest of the gear when I didn't want to walk
from house to shed for hamming.
73, Jerry, K0CQ
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