---- NORM KNAPP <nkn...@twowayradio.net> wrote:
> Took down a set of DB212-3 dipoles in good shape with harness. I want to use
> them on 6m for a repeater antenna. I also want to add one additional dipole.
> I guess I will need to modify the harness and the dipoles as they are marked
> for 35.960 mhz....
> I will be mounting all four (or 3) on one leg of a tower that is 4 feet on a
> face. Is it worth my while to go for the 4th dippole? The loops are 155
> inches from tip to tip now. Looks like they need to be about 105 inches.
> Anyone with any tips, pointers or advise?
> Thanks....
Hi Norm...I've used a few sets of the db212s and can say that they are real
hard to beat. If the tower is 3 sided use the -3 and shorten the trombones and
harness. If the tower has 4 legs, use all 4 antennas and make up 3 harnesses
for 2 antennas each. If you are in an area which has a lot of blowing sand,
consider wrapping the trombones in good poly tape to reduce static. I know the
antennas are grounded, but it does make a difference. Also, when placing the
antennas on a tower, use one antenna stuffed between the other 2 to make a good
field spacing of the antennas. This would result in a spacing of about 0.8
wavelength.
Remember these antennas must be tuned against a suitable tower, not in free
air, and a couple of wavelengths off the ground. If you don't understand the 3
pairs harness, remember that antennas 1 and2 will be paired; antennas 3 and 4
will be paired; and pair1,2 and pair 3,4 will be paired . Thus 3 pairs!
good luck
Jeff N5SXQ
