Spektrum Rx brownout

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Spektrum Rx brownout

Postby Helikiwi » Tue May 04, 2010 9:49 am

At one of the parks I fly 3 flyers have had brown outs in 4 models at roughly the same spot in the park - any ideas what could do this
It is a spot in the park where models turn to head back to the landing area
Only happened to spektrum rx's

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Re: Spektrum Rx brownout

Postby flying-things » Thu May 06, 2010 10:30 pm

3 different rx's cutting out in the same spot? Which rx are they? Have you placed the airplane on the ground in that spot and range checked it?
Seems like strong interference. Did this all happen on the same day?
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Re: Spektrum Rx brownout

Postby RCModelReviews » Fri May 07, 2010 12:53 am

It would be worth getting one of the USB-based spectrum analyzers and hooking it up with a laptop then seeing what the noise profile is like at that particular point on the field.

There maybe some nasty stuff lurking and, as the tests show, the Spektrum isn't as resistant to interference as the frequency-hoppers or tri-frequency systems.
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Re: Spektrum Rx brownout

Postby siang » Sat May 08, 2010 3:15 pm

Geeeze, that's a worry. I wonder if those heli expert ever experienced brownout/lost controll when they fly their heli with Spektrum. It'd be a total tragedy. :)
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Re: Spektrum Rx brownout

Postby GeicoGecko » Thu May 13, 2010 12:34 pm

Doesn't brown out suggest power loss as opposed to signal loss?
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Re: Spektrum Rx brownout

Postby Bingo » Thu May 13, 2010 9:20 pm

GeicoGecko wrote:Doesn't brown out suggest power loss as opposed to signal loss?


Yes
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Re: Spektrum Rx brownout

Postby wldingrod » Sun May 16, 2010 6:54 am

Its odd that no one with a bind and fly aircraft built by horizon seem to complain of brownouts etc.
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Re: Spektrum Rx brownout

Postby GeicoGecko » Mon May 17, 2010 4:15 pm

All of the bind and fly aircraft I have seen have been using Lipos. The brownouts really come in when you're using a 4 cell NiMh etc under high current draws.

This thread is actually referring to what looks like interference as opposed to brownouts.
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Re: Spektrum Rx brownout

Postby kneedrag » Tue May 18, 2010 1:01 am

Running a Lipo does not prevent you from having a brownout. If you watch the voltage of your lipo during flight it varies depending on what the plane does. It just takes a moment for the voltage to slip past the point of no return and you have a rx brownout. Even running a dedicated BEC does not prevent this from happening as most BEC's require a certain input voltage to supply a set output voltage.

Generally this however happens only on large models with 4 and more digital servo's. Jacko on the forum was quite happily flying his large hotliner around until he got the Aurora and remote battery monitoring and realized how dangerously close he had been to losing the model to brownout when he moved all 6 servo's at the same time.

Lipo's while they are nice are not going to end a lack of voltage.
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Re: Spektrum Rx brownout

Postby RCModelReviews » Tue May 18, 2010 1:32 am

Most people woefully overestimate the ability of their BEC.

The linear BECs built into most speed controllers aren't particularly good and they generally have current-limiting which means that when they get hot or if you try to draw too much current they respond by dropping the output voltage. Result=*splat*, especially if you're running Spektrum.
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