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The lack of hypotheses is more due to the lack of data. Things happen so fast at game day and folks are running back and forth troubleshooting the booth and other things, that we can only rely on poor recollections making it more an exercise in wild guesses. If I had to guess, I would say it was due to the thicker plywood causing more jolting (although it didn't seem to correlate with the timing of outages) and possibly wifi interference. i am going to talk with them about the USB extension cable and a shock absorbing solution for the cortex.
Sorry if I miscommunicated, they have the power pole to white adaptor at Cowtown.
The Cowtown folks are awesome. They go out of their way to help. It is a fantastic hub.
Thanks as always.

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With yall's assistance, we may have figured our disconnect problem out.
After not having a problem for a week, we began getting sporadic instances with multiple 1-2 second disconnects (Vexnet light turns red and quickly turns back to green) that could not be reproduced by anything they tried. We were finally able to reproduce it by holding the joystick near a phone. This phone was not running a hotspot, and it even happened when the phone was in airplane mode. Since removing phones from the drivers box (out of their pockets) we have had no more disconnects.
Why this happens, we are not sure. It is still inconsistent and some phones are worse than others. It does appear to be related to proximity. Front pocket is worse than back pocket.
Our only theory on why it happens in airplane mode, is that the evil phone makers are tracking us even when we think everything is off. Most of our theories are based on the evil phone makers.
Thank you all, especially Mr. Graber.
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You are Welcome, and thanks for the new and tested hypothesis.
(In hindsight), it should be expected.   
 The flat cortex was improved to the 'turbo bump' cortex, because even a half-inch of extra distance between the X MHz CPU stuff and the 2.4MHz wifi key makes a noticeable difference.  Maybe the underside of the top-case is coated with conductor shield as well.  It is even possible that a change in the robot code you are running on the Cortex could change the interference noise pattern.  

That also suggests that wrapping your on-robot gopro or phone-cam in conductor may reduce interference as well.

I'll forward this to the other Regionals.  Thanks again.

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We had no problems on our practice field after removing cell phones from the drivers pockets.
At Regionals, problems returned. Brief red Vexnet light flashes which were hard to reproduce on purpose.
Luckily, Mr Graber was there and, despite being pulled in all directions by teams with problems, he methodically and patiently worked with our team. As an aside, Mr Graber won the volunteer of the year award for our region.
Backing away from the robot showed similar disconnects but we were able to get 40 feet away before it happened.
Used the USB extension and disconnect problem appeared to be better, but still happened. Added the dongle and problem appeared to be solved in practice. Unfortunately there was not much time to practice.
In competition, disconnects were few but did occur despite the changes they made. 
There were apparently lots of disconnect issues at the competition although we were unable to find out what the other teams were experiencing. One field was particularly problematic and they asked the audience to clear the 2 rows closest to the field. Did not hear if that helped.
After spending a lot of time on this issue, I am left with the conclusion that the problem is multifactorial, based on the various ways the connection can be interfered with. There is not a single solution.
I think all of the solutions suggested earlier should be considered by teams wanting to avoid the problem.
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