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Old 10-29-2008, 10:08 AM
  #23  
idedave
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Default RE: Futaba 7C FASST or JR DX7 Spektrum

A very interesting and informative post from Gord. He validates that the Spektrum system takes a long time to boot up on the ground. Unfortunately, this is exactly the problem. Also the '4.8v is as good as dead' comment is very revealing. NiCd batteries still have most of their energy at 4.8v. A system that has so little operational headroom that the difference between 5.2 v and 4.8 v is all that stands between you and a loss of control is pretty scary.

When I talked to Spektrum support, the first question they asked me was 'did I have a binding servo'. This was the trigger that lead me to the issue. This is a known problem but there is no easy fix because this particular implementation of spread spectrum has an inherently long start up time.

I completely understand that people want to assure themselves that their radio is 'rock solid' and I certainly don't want to make anyone upset. I am just reporting what I have seen and my conclusions. I hold a Master's degree in digital electronics engineering so I have some vague idea what I'm talking about. Of course, anyone can be wrong.