Antenna placement

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DjMtrx3
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Joined: Thu Aug 28, 2003 9:53 am

Antenna placement

Post by DjMtrx3 »

Quick question and I figured this would be the place to ask with the people that know there stuff. I have a NMO mount UHF antenna on my Ford E-150 as of right now right about the dome light. I want to add an 800 MHz antenna also a NMO mount. How far should they be separated on the roof? I was looking around the internet and saw things like 14 inches and 22 inches, but what would you guys suggest? Thanks

Alex
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KG6EAQ
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Post by KG6EAQ »

As long as it's more than 6" I wouldn't worry about it. The safe measurement is at least 1/4 wave on the lower frequency antenna. If you can space it out more go for it.
-Robert F.
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wa2zdy
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Post by wa2zdy »

Yep, the quarter wave at the lowest frequency is the correct number to avoid interaction between the antennas. That doesn't mean two UHF antennas can be 6 inches apart without receiver desense, just that the two antennas will not screw up each other's radiation patterns and SWR.
Chris,
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