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Unread 03-04-2012, 07:47
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Al Skierkiewicz Al Skierkiewicz is offline
Broadcast Eng/Chief Robot Inspector
AKA: Big Al WFFA 2005
FRC #0111 (WildStang)
Team Role: Engineer
 
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Rookie Year: 1996
Location: Wheeling, IL
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Re: Intermittent connection on field only

Quote:
Originally Posted by rbtying View Post
Team 846 had similar problems at New York Regional, which were resolved by swapping the power distribution board. Though it will not pass inspection, you can try mounting a spare PDB as a custom circuit off of one of the 40A breaker slots, and powering the radio off of that.

We will likely have more data on this phenomena later, as we plan to scope out the failed power distribution board under load. It is perhaps notable that we have measured large ripple voltages (up to 0.6v on a WORKING board) on the 5v supply output, and that this is likely a marginal condition for the D-Link, which expects 5v +/- 5%.
Yep, one and only one PD. However, ripple is not normal and the five volt output is to be used for the camera only. The correct wiring is to connect the five volt convertor to the +12 volt 'radio' output on the PD. The output of the convertor then feeds the radio.
Any idea what frequency the ripple was?
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Good Luck All. Learn something new, everyday!
Al
WB9UVJ
www.wildstang.org
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Storming the Tower since 1996.