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To vee up or vee down
- Thread starter nfsus
- Start date
There's some useful info in the link posted below.
www.worldwidedx.com
Dipoles
Hello, I have'nt been on for a while, I have a homemade dipole that a freind made for me some time back and now i would like to put it up, my question is i would like to set it up along the side of my house, i have a 35 ft of a 20 and 15 ft of metal pipes, ok, i was thinking of some way of...
Here's another
www.worldwidedx.com
CB dipoles
what can I expect with one? And why does everyone say "dipoles keep an honest man honest" lol
Thanks but not what I was looking for. I need to give more Info.
I run a 135ft ocfd that's a flat top at 55ft above ground to the feed point unun. The ends are adjustable as is the feedpoint on height.
As I lower the unun the ends will either drop or they will for a right side up vee shape. As I raided the unun it mors more toward a flat top.
I orig was wondering if anyone had played with the height of the feed point/ vee shape in comparison to any other shape, like a flat top or inverted vee.
I am thinking I can leave the ends and raise or lower the feedpoint to make adjustments in height so nvis will be more possible or dx will be more possible when its higher. Like rf gain by height, haha. But all I've ever seen is inverted vee, i assume because of the feedpoint impedance issue. But each band will be different too so it's just an experiment
I run a 135ft ocfd that's a flat top at 55ft above ground to the feed point unun. The ends are adjustable as is the feedpoint on height.
As I lower the unun the ends will either drop or they will for a right side up vee shape. As I raided the unun it mors more toward a flat top.
I orig was wondering if anyone had played with the height of the feed point/ vee shape in comparison to any other shape, like a flat top or inverted vee.
I am thinking I can leave the ends and raise or lower the feedpoint to make adjustments in height so nvis will be more possible or dx will be more possible when its higher. Like rf gain by height, haha. But all I've ever seen is inverted vee, i assume because of the feedpoint impedance issue. But each band will be different too so it's just an experiment
This is a fair idea of what it does as I raise or lower. It's what I'm wondering about. If it can be helpful to be able to raise and lower while using it to increase nvis or dx or limit trash interference.
Attachments
Off the bat I would say try it and see?
Good question then you mentioned NVIS.
7mhz and lower in freq for NVIS.
If you at 55 ft AGL you are NVIS.
I have a 40/80 meter fab dipole at the shop 65 feet to feed point inverted V.
At house I have 40/80 meter dipole in a lazy U configuration feed point 30 ft AGL.
I see no difference in TX or RX and neither do any of the guys I rag chew with.
Try your experiment and find out. Be interesting to see results.
Good question then you mentioned NVIS.
7mhz and lower in freq for NVIS.
If you at 55 ft AGL you are NVIS.
I have a 40/80 meter fab dipole at the shop 65 feet to feed point inverted V.
At house I have 40/80 meter dipole in a lazy U configuration feed point 30 ft AGL.
I see no difference in TX or RX and neither do any of the guys I rag chew with.
Try your experiment and find out. Be interesting to see results.
Assuming the antenna is a textbook half-wave, center-fed dipole, the feedpoint is the highest current point; maximum RF at that point, tapering off pretty equally to the ends. With a normal "V" configuration, with the center point at the bottom, a lot of the RF that would normally radiate to receiving antennas all over the world just goes into the ground. Why? Because it's seeking ground, and the bottom of a V is closer to ground than some receiving antenna in Baluchistan.
On the other hand, an inverted vee (vertex at the highest point) puts that max current up a bit closer to where it can do some good. Hello, Baluchistan!
On the other hand, an inverted vee (vertex at the highest point) puts that max current up a bit closer to where it can do some good. Hello, Baluchistan!