10 meter beam project

[airplane1]

some more pics, if you look around you can see it was pointed in the open but to the sides and back were the house and a few trees and garage. I believe it should be fine though. I was sitting about 4" under it while tuning.

AP

 

[Robb]

Niiiice!
Just a thought here.

I would put a plastic/rubber cap/plug on the end of that gamma. So that water can't get in there and affect your SWR/tuning.
Might also use a 10 ft length of coax to be sure that your presence didn't affect the tune . . .

 

[airplane1]

Thanks Robb, was thinking about cap for the end too. for now I think I will shoot some caulk in the end till I get a cap. I used a 15 ft coax but you can not see it in the pics, I walked out from the antenna so as not to affect it and looked at the swr from a distance. Then when I went under the antenna to take the pics of the MFJ I watched to see if the swr changed and it did not move a bit.

AP

 

[Robb]

I set mine up by pointing it upward resting on the reflector.
It held the same tune when I set it on the push-up pole for final use.

Congrats!

 

[wavrider]

I set mine up by pointing it upward resting on the reflector.
It held the same tune when I set it on the push-up pole for final use.

Congrats!

Best way to do it, sit it on it's reflector point it straight into the air and tune it. It may or may not vary once it is in the air but if it does vary it will not be by much.

Looking great, caulk will do, I fill the ends of mine full of 3006 caulk from the local home supply store. Cheap and easy to use.

Remember to use coax seal.

Paint it pink, pink yagi's are more efficient.

 

[airplane1]

I am going to mount the antenna on a pipe pounded in the ground pointing straight up, Slide the beam on with reflector facing down and retune it that way. Do not know if swr will change from what I am reading now but will see. I will be getting it up on the tower for testing as soon as my HD-73 rotor gets back from Norm's.

I do not have any thing to compare it to performance wise as I never had a beam before just omni antennas so it should be fun.

AP

 

[wavrider]

AP you will definitely enjoy the added gain both on TX and RX of the yagi, between the beam and the vertical the yagi will be better biggest percentage of the time, other times mother nature will decide which antenna is best for propagation conditions.

The sweet thing about yagi's is the gain, many contacts will ask if you are running an amplifier, nice to say nope just a home brew yagi and 100 watts , I even turn rf power down to 5 watts and make contacts, fun to play with and see just how good the antenna system really is, QRP is a good test.

 

[airplane1]

Was thinking, Anyone know what beam F to B should be? The way I designed this it is 16 dbi but if I play a little with spacing I can get it to 23.8 dbi. It will only drop from 9.06 dbi gain to 8.82 dbi which is not a noticable drop in gain but a pretty good gain in F to B.

I guess I will change the spacing this weekend.

AP

 

[wavrider]

Not sure on the spacing, several programs available online for optimizing yagi's.

If you are mainly going use it for 10 meters I would go with max gain dimensions, if it will be used on 10/11 meters then the added rejection will be nice.

Either way it sure looks nice, good job on the build.

 

[Robb]

11 meter DX sytems

 

[wavrider]

The Ultimate Guide to 11 Meter CB Antennas

Some more reference material about half way down the page is a chart showing forward gain and f/b rejection,

 

[airplane1]

Thanks guys, I down loaded QY4 free and it is very nice. I ran the program with my 4 ele info and then optimized the front to back using spacing of the elements and came up with so good figures. I am going to use it on 10 and 11.

This is fun.

AP

 

[wavrider]

Great on the optimizing the yagi, antennas are a lot of fun and it is great to make the contact knowing you built the antenna home brew.

Enjoy and have fun.