Tom,
If space is not an issue, why not do some phased dipoles rather than
perpendicular ones? I also am not sure what kind of interaction you'd get
between the two antennas that are the same length set perpendicularly to
each other. The only setup I saw with perpendicular dipoles had the
80-meter in one direction and the 40-meter 90 degrees opposite to it.
As for the Cobra UltraLite, it sounds like a nice antenna. But, the coil
design, read shortened design, means it will be compromised on the lower
resonant bands. So, you won't get 75-meter performance equivalent to a
dipole using the 73-foot version.
To add to your antenna considerations, if you are going to be a Michigander
for some time to come, maybe you just want to get a new tower. If you put a
beam on top, you could get a sloper and use the tower as part of the design,
with the beam being a capacitive tophat. They really work well.
As for RG8X, I wouldn't worry about it on the lower frequencies. I have an
AL811H and have fed mine with 600-plus watts up to 21MHz with no problem. I
wouldn't use that stuff on VHF of course, due to the higher lossses.
----- Original Message -----
From: "tom behler" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, July 18, 2010 3:27 PM
Subject: Need some input on HF wire antennas for the Michigan house
> Hi, all.
>
> Well, I have been bending the ear of Kevin (K7RX) off list on this topic,
> and thought I'd seek input from others here on the list about an antenna
> dilemma I'm having when considering the best HF antenna arrangements for
> the
> Michigan house.
>
> Here's what I'm thinking, in general, but I need some help with specifics.
>
> When I moved to Colorado last July, I donated my tower, triband, beam,
> etc.,
> to an EOC one county to my north, so I will be without a tower. In
> considering various options, I feel that my best arrangement for HF would
> be
> wire antennas of some sort. Keep in mind that I need antennas that will
> accommodate 600 or 700 watts, due to my recently-purchased Ameritron
> AL811H
> amplifier.
>
> I do not necessarily have a problem with room on the Michigan property,
> although coming up with adequate antenna supports might be a slight issue,
> though ultimately solvable.
>
> What I'm thinking is this: I'd like to have two dipoles, arranged
> perpendicular to each other, so as to cover as many directions as
> possible.
> My TS480, and my Tentec 238A manual tuner both have antenna switching
> capability, so switching between antennas will not be a problem.
>
> One of the dipoles that I'll use, of course, will be my trusty Alpha Delta
> DXCC, which I had up here in Colorado, and used regularly for the
> Cross-country blind ops net.
>
> I am trying to decide what to do for the other wire antenna. I thought I
> had a line on a Carolina Windom, but that seems like it will not work now,
> since the ham who was going to work a deal with me has gone to Florida for
> an indefinite period of time. I could get another Alpha Delta DXCC, but
> would like to try something that might get me on 160 meters if possible.
>
> Some folks on this list have discussed the Cobra lite series of antennas,
> and I might consider that as a possibility. Do those antennas cover 160,
> and can they handle 600 or 700 watts?
>
> Also, I have a question about coax.
>
> In Colorado, I fed my Alpha Delta DXCC with RG8X coax, and didn't seem to
> have any adverse effects when running more power with the Ameritron amp.
> Some have told me that this is not a wise thing to do, and that I should
> consider bigger coax, like RG213.
>
> Does anyone have any thoughts on this question as well?
>
> I know this is a lot for one e-mail, so I appreciate everyone's patience
> in
> wading through it.
>
> I'd like to place an order soon for what I need, so the stuff will be
> available in Michigan, once we are back there for good next week at this
> time.
>
> 73 from Tom Behler: KB8TYJ, still in Colorado, but only for a few more
> days
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