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Discussion Starter #1
I'd like to start a discussion on what would be considered good GH parameters from a building perspective.

I'd like to know your opinion on the following.

1. Maximum feed gap
2. Maximum gap between colinear reflectors.
3. Maximum length of a half reflector (half of the max antenna width)
4. Maximum antenna height

The general question is at which point one would consider those parameters to be a more important decision factor than the gain/swr curves?

Please have the numeric portion of your replys laid out in the form:

max_feed = value
max_gap = value
max_hlen = value
max_height = value

so I could copy to a spreadsheet
 

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from a building perspective.
So, youre looking for design constraint measurements from a practical available size standpoint ?

1. Maximum feed gap That should be as far as a typical balun can stretch for mounting. Baluns vary in that regard. And you could use extenders. I would say about 5 inches.

2. Maximum gap between colinear reflectors.
That would be limited by the plastic tube you could get. The grey pvc rain gutter ferrule is 5" (perfect for 3/8" tubing), and you would want to leave about 3/4" of the ends in there, so that would leave about 3.5" for the gap. Of course there are other mounting methods and other tubes.

3. Maximum length of a half reflector (half of the max antenna width)
The max width of commonly available mesh sold, is 48". The longest element on Vhf antennas with 3/8" tubing was 54", and that element typically took a beating. I would say 39" (1 meter) in length max for stand alone 3/8" tubing so it would hold up over time.

4. Maximum antenna height
You would want to work on an antenna without using a step ladder. A six foot tall person can comfortably reach and use pliers up to about 90". If the antenna is mounted in a 12 inch stand, that would leave about 78 inches as the maximum height.
 
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