Radio Shack Sputnik Build with 800mhz added?

[thomast77]

I am going to build a Radio Shack 20-176 Sputnik type antenna with an addition of 800mhz. Not sure if it can be done so I wanted to share my ideas and see if there are any antenna design professionals that can give some input. I have no Idea how to use antenna design software. I have messed with it some but just don't have the time.

Anyway this antenna would be built just like the radio shack 20-176 Sputnik but with the addition of 800mhz elements. The main VHF element would be 18.108" cut for 155 mhz. The UHF elements would be 6.170" cut for 455 mhz The 800 mhz elements would be 3.283" cut for 855 mhz. and the three Ground plane elements are 5% longer than the main VHF element at 19.013".

Now the question is where to put the 800 mhz elements? Should they be mounted 90 degrees from the UHF elements as in 90 degree mount.png or should they be side mounted below the UHF elements as in side mount.png

Thank You all in advance for your input
Tom

 

[oft]

From what I have seen in other antenna designs, it should be like the picture on the bottom with the 45° elements visually perpendicular to each other.

However, I have seen designs where the antenna designer has gone approximately 1/4 to 1/2 the distance up the main VHF straight vertical element (the 18.108" one) and mounted the 800 hz (3.283" elements) there at 45° and visually parallel to the 455 MHZ UHF elements (the 6.170" elements".

Now, the question is, which is the better setup in reference to reception and gain, the 45° elements visually perpendicular to each other or the 45° elements visually parallel to each other? Also the same question to me would also apply to all elements mounted common to the bottom of the vertical element or spaced out in reference to the vertical element?

 

[W6KRU]

Take a look at this for some ideas.

http://www.qsl.net/n4yek/scanner/antenna.pdf

 

[oft]

DDan:

That was the exact picture I was remembering in my head when I stated in my earlier post about "I have seen designs where the antenna designer has gone approximately 1/4 to 1/2 the distance up the main VHF straight vertical element...."

My problem was, I did not remember where the webpage was that had the article, thanks for providing the info.

 

[W6KRU]

You're welcome. Have fun.

 

[thomast77]

I have seen the design in the pdf before. I may have to experiment to come up with something that I like. But that's a lot of the fun of the hobby in my opinion. Thank You guys for the input