I am building a large scale gasoline-powered model and it will require 18"+ extensions. Do I need
voltage suppressors, noise suppressors, chokes or to take any other precautions?
In general,
there is no need for noise suppressors in current Futaba equipment.Some other brands’
current equipment do require this; however, Futaba does not.
Twisting servo extensions
lightly and gently
is a good idea, as it helps minimize the combination of
the 3 leads’ electrical fields. Heavier gauge extensions are highly recommended, both due to the length
of the leads and the high current drain of high torque, high speed, ball bearing or digital servos.
If you see radio interference in your gasoline aircraft, look first to the engine's installation. All ignition
equipment, including electronic kill switch, must be mounted 12+" (preferably 14+") away from all
radio equipment, including throttle servos. The ignition kill switch should always be on the opposite
fuselage side from the receiver’s switch. All pushrods to anything engine-related must be non-
conductive (nonmetal clevises are required, but alone are not sufficient).
My expensive, ball bearing servos “buzz,” “hum,” or “chatter,” especially when I first turn on the
receiver. My standard servos never did this. What's wrong? What do I need to do?
Modelers often report "servo chatter" in ball bearing servos. This may or may not indicate a problem.
First make sure the transmitter is a sufficient distance from the aircraft so that “swamping” is not
occurring. Then check your linkages and set-ups for binding, servos fighting each other on the same
working surface, and bad extensions. Be sure that there are no problems in your physical system.
Assuming there is no binding or other issues, buzzing is a common and harmless occurrence, and
indicates that your servo is "checking" itself for true center. There will many times be an audible
"buzz" from the servos, even when there is no noticeable movement. This is also harmless, as when
the plane is airborne, the wind will load the control surfaces, which will correct this small amount of
vibration and noise.
Many times if a modeler is using a 6-Volt receiver battery, or a fully charged battery, they will notice
buzzing, but, when the voltage drops slightly with some amount of load, the movement and noise
subside. This is commonly known as “a hot charge”, and is perfectly normal.
Digital servos:
Note that digital servos emit a high-frequency “hum” at all times. This is very normal.
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