Tom,
First, good news on the power supply. Sounds like no problem.
I think your G5RV sounds typical. Following is a link to a site with some
computer modeling of the G5RV. If I'm following this correctly, the first
batch of numbers shows swr's for all bands for a 102 ft. long dipole fed
with coax, or 300 ohm twin lead, or 450 ohm ladder line. Some of the
numbers are pretty high as you would expect.
Then comes a batch of numbers showing that same dipole fed with coax, but
with a 300 ohm section (typical G5rv). You can see how the numbers change,
and the examples you gave seem to be in this ballpark.
The G5RV is what it is, and while I used one in the '80's, I prefer coax
fed resonant dipoles. To each his own.
Here is the link:
http://www.qsl.net/k2hq/g5rv.htm
73, Steve KW3A
----- Original Message -----
From: "T Behler" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, December 27, 2007 9:09 PM
Subject: more G5RV stuff
> Hi, all.
>
> Can someone tell me what an acceptable SWR picture would be for a 102-foot
> G5RV antenna?
>
> I re-oriented my G5RV antenna today, by making the ladder-line run pretty
> much vertically from the antenna feed-point at the top of my 35-foot
> tower,
> to the coax that then goes into my shack from the base of the tower. I
> checked the connections between the ladder-line and the coax feedline, and
> they still seem to be good.
>
> My SWR's are a bit better, and the auto-tuners on both my IC746 and
> Kenwood
> TS480 now tune the antenna on 40 meters (which I couldn't say before), but
> the SWR's still seem quite high to me.
>
> On 40 meters, I get an SWR anywhere from about 5 to 1 down to about 4 to
> 1.
>
> The antenna has its best SWR readings on 20 meters, which you'd expect,
> but
> even here, I can't get the SWR to go much below about 1.8 to 1 in the
> center
> of the band.
>
> Again, at least now, the auto-tuners in both of my HF rigs will tune the
> antenna, but I'm wondering whether it's even safe or wise to use the
> antenna
> under these conditions.
>
> 73 from Tom Behler: KB8TYJ
>
>
>
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