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Old 14-Sep-2018, 12:30 AM   #2
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,355
Crossed dipoles form a turnstile antenna. In theory, it's a pretty good Omni with peaks at 0, 90, 180, and 270 degrees. There are slight nulls between those directions.
https://www.google.com/search?q=turn...iw=911&bih=363

But holl_ands modeled it, showing that it is a little less Omni that theory indicates.

https://imageevent.com/holl_ands/omni/fmturnstileacfmss

I don't do modeling, but that doesn't look like a 90 degree phase shift line between the crossed dipoles, so I don't have confidence in his model. How long is the feed line between your dipoles?
Attached Images
File Type: jpg Antennacraft FM Omni_1.jpg (150.5 KB, 65 views)
File Type: jpg Antennacraft FMSS_1_zoom.jpg (12.5 KB, 59 views)
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Last edited by rabbit73; 14-Sep-2018 at 12:59 AM.
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