Okay, found it - WA1X's technique for tuning a Moxon rectangle:
http://lists.contesting.com/archives//html/Towertalk/2005-03/msg00852.html
My apologies for not finding it sooner.
73, VR2BrettGraham
___
Elecraft mailing list
Post to:
Gil,
It performed well during our special event this weekend. We had it
up at an average height of 25'. We used it on both 20 and 40 meters
simultaneously using Array Solutions RF filters with a little 2nd
harmonics or phase noise on 20 from the 40 meter transmitter. We
were able to
W1CG replied:
one big snip
Presumably you know the dielectric constant of that insulation,
verified that the wire you have is in the same neighborhood
done all your modelling based on that figure?
I have previously assumed that any wire insulated or not, in space, has
the same velocity
Brett,
Tnx for the comments. Tried the antenna today and successfully
operated simultaneously with both transceivers on the phone
bands. There was some second harmonic noise of the 40 meter
transmitter on 20 when an ICOM 746 Pro was used at 100 watts; none
when a K2 at 10 watts was used.
W1CG continued:
To answer your question, I am using stranded, silver plated, teflon
insulated #16 wire. It is plenty strong. I have a 3/16 Dacron line
between the two poles to take the strain off the wires. This also
decreases the vertical bend and completely eliminates the horizontal
bend
Brett,
To answer your question, I am using stranded, silver plated, teflon
insulated #16 wire. It is plenty strong. I have a 3/16 Dacron line
between the two poles to take the strain off the wires. This also
decreases the vertical bend and completely eliminates the horizontal
bend of the
Stuart
Thank you for the insight. I calculated the % the wire lengths were
off by % the frequency was off, and I also moved the model up in
frequency (by shortening wire lengths in the model) by the amount it
differed from the measurement. In other words, the actual was about
200 KHz below
Charles,
With dual band close spaced beams, everything interacts.
You can try adjusting the wire lengths by the percentage you were off your
target frequency, or just operate them as they fell. They will vary with
height, and there is no compelling need to have them exactly resonant in
cases
Hi,
I need some advice on a wire beam I built for field day and special
events. It has two fiberglass poles 22' long spaced 45' with a wire
Moxon for 40 M on the outside and a two element 20 meter beam between
the 40 meter Moxon. It has there is little interaction between the
beams either
9 matches
Mail list logo
