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Unread 11-01-2008, 10:15
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Re: Flawed IR Design Confirmed

Quote:
Originally Posted by keen101 View Post
I have finally wired it up to a PWM cable. There should be no need for a diode now, since the PWM cable cannot provide reverse voltage. But, i suppose if i was really paranoid I could splice the red wire on it and add a diode there.
If you are using the PWM cable to connect it to the RC's PWM Output (which draws power from the 7.2V backup battery), the 0.6V voltage drop of the diode would likely cause the voltage to drop below the required 7V (or only work for a short time since fully charged backups can be up to 8.4V). Compatibility with the backup battery might be the reason there is no diode already on the board.

P.S. you can get reverse voltage from a PWM cable if you flip the connector and plug in only 2 pins (red to black). I've seen them plugged in that way on a crowded RC.
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