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Old 18-03-2013
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mpg200 mpg200 is offline
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Location: Bradford
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A capacitor fitted to a spare socket on the receiver should fix it. Any 4700uF 10V or better cap should do it. Savox and spektrum have caused me issues before. I did some tests and traced it down to poor BEC design compounded by savox power hunger.
Not all BEC are created equal. Some are better than others. From the ones I’ve tested LRP come out well, while cheapy chinese Speedos not so good.


Results:
Both BEC specified at 3A rating. And yes they both worked perfectly at 3A. However a savox can draw over 3.5A for very short periods this can cause BEC to fall over and drop its output volts so the receiver resets and causes glitches.


ToroPro 120A BEC rated 3A tested with electronic load set to 3.5A for 500uS duration.

(tek00013.jpg)

pale blue is load current, dark blue is BEC output voltage. You can see the output voltage dropping below 4V this is where a spectrum receiver will fall over.


LRP Sphere DEC rated at 3A tested with electronic load set to 3.5A for 500uS duration.

(tek00014.jpg)



pale blue is load current, dark blue is BEC output voltage. You can see the output voltage does not drop below 5V all should be well with this


The function of the capacitor is to supply the energy to fill in the voltage drop when the load is high. Basically smoothing out the BEC voltage and not have nasty drops like in tek00013.jpg
Attached Images
File Type: jpg tek00013.jpg (19.6 KB, 8 views)
File Type: jpg tek00014.jpg (19.2 KB, 5 views)
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