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WN9HJW
06-02-2012, 08:14 AM
Post Deleted

KG4CGC
06-02-2012, 08:22 AM
Tell them it's a 3rd of a wavelength over a half wave dipole ie; operating in colinear mode.
If you can't dazzle them with sparkly baubles, baffle them with Bullshit.

N8YX
06-02-2012, 08:37 AM
Make the top section 93ft overall, change the ladder-line length to around 44ft and get coverage of 40-20-17-12-10M with <2.1 VSWR. Feed with 1:1 current balun and LMR400 or better to the radio. I use RG-213 with mine.

WØTKX
06-02-2012, 08:46 AM
Doublet.

KC9ECI
06-02-2012, 09:10 AM
Which reminds me, I dropped one side of the G5RV to move the camper out and the boy ran it over with the mower. I sat out in the yard in front of the fire pit last night considering what to do next. I'm thinking I can convert the G5RV to a G5RV Jr easily enough, but as long as I've got it down, maybe I'll replace it with an inverted L. No particular reason, I'm just bored by the current lash-up and feel the need to try something different.

NY3V
06-29-2012, 09:36 AM
...If you can't dazzle them with sparkly baubles, baffle them with Bullshit.

That would be stooping to the low level of Faux News and GOP diatribe. ;)

W3WN
06-29-2012, 10:44 AM
When I tell people I'm using a 3/2 wavelength dipole on 10 meters, that seems to confuse a few.

They ask things like "What is that?" or "What frequency is that for?" or "dipoles are 1/2 wavelength"

If I say "using a 40 meter dipole on 15 meters" that seems to be OK. If I say "using a G5RV on 20 meters" that is OK.

Maybe I should be saying "Using a G5RV Junior with the ladder line section removed and replaced with coax all the way to the radio"?

Maybe I should just say "dipole".If you wish to educate them, and if they wish to be educated, you tell them this:
Dipoles (with impedances of roughly 75 ohms) are odd half-wavelengths. 1/2, 3/2, 5/2, etc. Even half-wavelengths (1 wave, 2 wave, etc.) have an impedance approaching infinity.

That's why a 40 meter dipole works on 15, but not on 10 or 20. (That's sans tuner/matching network, of course)

If you don't wish to do so, or (more likely) they don't wish to learn, then just say 'dipole' and don't bother them with the details.

...and if it's hung as an inverted V instead of a true in-the-plane dipole, the impedance is roughly 50 ohms. And THAT is why most radio grade coax that we use is at or near one of those two impedances...

N8YX
06-29-2012, 11:37 AM
That would be stooping to the low level of Faux News and GOP diatribe. ;)
Keep the political stuff out of the technical areas, please.

kb2vxa
06-30-2012, 11:33 AM
"Which reminds me, I dropped one side of the G5RV to move the camper out and the boy ran it over with the mower. I sat out in the yard in front of the fire pit last night considering what to do next."

Throw the kid in the fire pit and throw the mower in after him. With that out of the way put up the antenna of your choice.

X-Rated
06-30-2012, 03:37 PM
When I tell people I'm using a 3/2 wavelength dipole on 10 meters, that seems to confuse a few.

They ask things like "What is that?" or "What frequency is that for?" or "dipoles are 1/2 wavelength"

If I say "using a 40 meter dipole on 15 meters" that seems to be OK. If I say "using a G5RV on 20 meters" that is OK.

Maybe I should be saying "Using a G5RV Junior with the ladder line section removed and replaced with coax all the way to the radio"?

Maybe I should just say "dipole".

I am assuming the 3/2 dipole is around 52 feet long then? Where do you feed it?

X-Rated
06-30-2012, 03:49 PM
http://i104.photobucket.com/albums/m165/n9xr/teddybear.png

At 35 feet, a flat top 3/2 wave 10M dipole has a teddy bear pattern. Aw. So cute. But remember. Don't feed the bears.