I'm working on building the ARRL dual moxon antennas, but the article isn't very detailed where I'd like it to be and a little over detailed in some places I wish it weren't.
If you want to look, this is the URL (http://www.arrl.org/members-only/tis/info/pdf/0108038.pdf)
1. What are acceptable ways to terminate the paralled 75 ohm matching sections? I'm thinking now I'll just terminate them to a couple of ring terminals attached to the mast rather than terminating each one with a bnc and teeing them.
2. How do I feed the 70cm and 2m with the same feedline? should I just tee a 50 ohm line to two equal length 50 ohm sections?
3. This is more of a comment... I'm wagering the uhf version doesn't work at all... measurements are given to the hundreth of an inch - and then you solder a big ring lug to the end of it!
4. Are there any other good techniques for setting the distance between the reflector and driver besides heat shrink?
The 70cm antenna is using #14 galvanized wire, and I can't think of anything small enough to hold them in place well. I found that the 3/16 rod for the 2m moxon will work great with 1/4" nylon tubing.
Thanks for any feedback - I'll probably have more questions.. I'm sitting here with a half-made 70cm turnstyle, and am about to start on the 2m version.
Whew - I'm beginning to think that a $1000 investment in rotators and antennae isn't such a bad idea after all!
Scott Wilson NW2S
On Jul 31, 2007, at 8:08 AM, Scott Wilson wrote:
- This is more of a comment... I'm wagering the uhf version
doesn't work at all... measurements are given to the hundreth of an inch - and then you solder a big ring lug to the end of it!
Scott - A good rule of thumb for tolerances is for them not to exceed more than a degree of wavelength, with 360 degrees being one wavelength. At 432 MHz this is about 0.2 cm or about 0.080 inches, which can be measured accurately enough with a steel rule. - Duffey
-- James Duffey KK6MC/5 Cedar Crest NM 87008 DM65