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Homebrew Co-phased Ground Plane Antennas

I tweaked around with the co- phased antenna and was able to get a swr reading down to 1.3 to 1 on channel 1, 1.2 to1 on channel 20, and a 1.1 to 1 on channel 40. 38 lsb is my main concern so I'm happy with 1.1 to 1 on the upper channels. Now I just need to get her up a little higher and a rotor. But I'm just going to get her up higher for now so I can talk on her.:giggle:
 
Incase anyone was wondering what I spent to assemble this antenna, I've got $230 dollars in it. I had to by the two 102 ss whips and the four 4ft Wilson antennas, I didn't have any extra coax so I had to buy coax. So I wouldn't consider this a cheap antenna by no means, could it be built cheaper? Definitely, if a person had all the materials on hand it could be built cheaper without a doubt. HomerBB could probably slap one together in an afternoon with bubblegum and ductape and walk all over my setup, LOL, he is the MacGyver of homebrew. I can't take any credit for the design of this antenna, that would go to Mowerjunkie from his Utube channel. But I am proud of how it turned out, it looks like I could have bought it from a manufacturer, (just my opinion) at least I don't have fishing poles attached to this one:ROFLMAO:
The wind was gusting pretty bad today so I didn't get the antenna in the air, but tomorrow it's going up one way or another.
 
I realized I never posted a picture of the co phased antenna in the air, and everyone always says no pictures, it didn't happen. Today is my first day back home and it's a nice day so I thought I'd take a picture of it in the air. It still needs a rotor, but it's up and running, just wish DX would start rolling around here. My wife said we had high winds while I was at work, got home and it's still standing. 20220414_130947.jpg
 
Thank you Homer! That means a lot coming from you, the home brew guru.
I'm proud of the way it turned out and the black paint I used blends in with the background, so it's not very noticeable from the road. I messaged Mower Junkie on his Utube channel and he actually replied which I thought was really cool. Hopefully I one day make contact with him using his antenna design, that would be awesome.Screenshot_20220414-230131_YouTube.jpg
 
Wally, I use to make a Starduster kind of vertical GP antenna out of 4 or 5, 102" SS whips, with an A99 hub, using a mobile mirror mount. See images below.

With these full-length 1/4 wave whips, my SWR Bandwidth and Match were almost perfect...over a nice wide range <2:00:1.

Up high the performance was also great compared to other GP's used if the tips of the antennas were anywhere close to the same tip height.

I would also think the shorter mobile antennas, you used for the GP, would also work similar. If you can find some extra SS whips, beg, or borrow, and try them.

Also make sure your feed line is not radiating, acting like part of your antenna.

Eddie
 

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Wally, I use to make a Starduster kind of vertical GP antenna out of 4 or 5, 102" SS whips, with an A99 hub, using a mobile mirror mount. See images below.

With these full-length 1/4 wave whips, my SWR Bandwidth and Match were almost perfect...over a nice wide range <2:00:1.

Up high the performance was also great compared to other GP's used if the tips of the antennas were anywhere close to the same tip height.

I would also think the shorter mobile antennas, you used for the GP, would also work similar. If you can find some extra SS whips, beg, or borrow, and try them.

Also make sure your feed line is not radiating, acting like part of your antenna.

Eddie
I may get some more ss 102 whips, my initial plan was to use only 102s . I could also use some better coaxle.
 
Finally!!! Made contact with a local on channel 40 am. He goes by Enterprise, he was in Stigler, Oklahoma about 22 miles from me. I got a good report on my signal and clarity, told me I pegged his meter out. I was flat out barefoot, so I was tickled to death with that. That's the very first contact I've made with the co-phased ground plane, what made it even better is that he ask what kind of antenna I was using because I was coming in so strong:)
He also told me if I monitor ch 30 am there's a group of guys in the local area that talk in the evenings quite a bit.
 
When I was in high school, the idea of a "Beer Can Vertical" came up. The school's Ham Radio Club gathered enough such containers with the aid of our parents and from the club's Advisers, who advised us not to help with the gathering of parts.

Of course, back in the early 1960s, the cans were eminently solderable, and 20 meter verticals sprouted from the electronics lab. You would not beLIEVE how many folks could look from the street about 150 feet to the antennas and with just their naked eyes identify the brands!

We ceased using these Skyhooks of Satan before the school board got involved!
 

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