Thanks to everyone for the suggestions on my sloper questions.
There are a lot of emails I've gotten directly back directly as well on the
reflector............
Most told me that at the height of my 75 foot tower, my 1/4 wave slopers
would act more like low dipoles, and that they would put out a higher angle
of radiation vs other alternatives.
Shunt feeding the tower was the most popular response under my circumstances
to put out a big signal off the 75 foot tower. But for me, it is a problem
because my guys are not insulated...
Maybe I should just take the first 15 feet or so of the inverted L out away
from the tower at about a 45 degree angle, using some rope and a fence post
to bring it out, so that the wire going up the tower stays out of the way of
the log periodic elements.
Pulling it out this far will also bring it further away from the tower vs the
way I used to have when it was pulled only 4 feet from the tower-
If I put the Inv L wire so that it goes behind the boom of the bottom log
periodic, which is not on a rotor but rather fixed at 30 degrees towards EU,
it should stay out of the way- (The LP's are only on 14 foot booms so I just
need to go out 7 feet at an angle and have at least a 8 or 9 foot side arm at
the top to support the Inv L.)
The only problem is that in our winter storms, I'm asking for it by bringing
the Inv L wire out so far from the tower if the sidearm is made of wood-
That's what got me started on the 1/4 sloper idea in the first place. With
90 1/4 wave radials for 160M off the tower legs, my 1/4 sloper for 30 meters
has been a great antenna and I thought that going to a 1/4 sloper for 160M
would work well too, but I didn't take tower height into account- .
The top off my 30 meter sloper is over 1/2 a wave length above the ground.
The top of my 160M sloper would be less then .15 wave length above the
ground.....does this account for the higher angle of radiation?
As for the phasing idea, no one thought it was a good idea. But I did get a
few suggestions that due to the broadness of the slopers, putting one up east
and west and switching between them as I would any other antennas on the
tower, would be a good way to go- Can anyone comment on what the modeling
shows as far as angle of a Inv L vs a 1/4 sloper utilizing a 75 foot tower?
And does pulling the bottom of the Inv L out away from the tower about 15
feet at a 45 degree angle seriously effect it's performance? If no, then I'll
just go with the Inv L. From what I've been told, my guess is that the Inv L
will look better on the models-
Of note, I did get one very positive response from W6OSP who uses a 160 meter
1/4 sloper off his 75 foot tower, with no radials, and it has work very well
for him considering he's worked around 160 DXCC countries from W6....the
sloper is off the ground at around 8 feet and he has found that adjusting the
slope of the antenna had a significant impact on the tuning of the antenna.
I also found this to be true with my 30 meter sloper- But he stated his
ground is very good while my ground consist of loamy soil...so I'm not
confident that I'll get the same performance-
73 Paul N0AH
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