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Lo-and-behold, only the same connections came in (1,8,13,14,15 and 17), but, initially at least, no others.
Went out to site 4 and discovered the issue with the blue_check.sh script. However, then noticed that several stations started connecting by themselves, despite the bug in the script. So I believe the communications are better from the dorm deck than from the pole on the trailer. To work from the trailer, I believe the radios would have to be raised.
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