RE: How do I use a separate battery to backup in case of BEC failure?
You might want to look here.
http://www.emsjomar.com/SearchResult.aspx?CategoryID=4
We use to make these (he had kits) in the good old days.
The real question is how did the BEC fail? Overheat do to lack of air flow. Or Overheat from too much current draw ( stalled servos).
Or was it a mechanical failure wire or PC board broke?
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