JR Vibe 90SG - General Radio Setup Information

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GENERAL RADIO SETUP INFORMATION
THROTTLE ARM/SERVO HORN POSITIONS
Toachievethecorrectpositionofthethrottle/servoarm,itmaybenecessarytore-positionthethrottlearmonthe
carburetor.Itmayalsobenecessarytoadjustthelengthofthethrottlelinkageslightlytoachievethefullopenand
closed positions of the carburetor.
Itisalsopossibletoincrease/reducethetravelofthethrottleservothroughthetraveladjustfunctionfoundinmost
computerradiosystems.Ifthisfunctionisused,makesurethevaluesforthehighandlowpositionsremainequal
(samevalueforhigh/low).Ifthesevaluesarenotequal,itwillcreateadierential,orunevenmovementofthe
throttle,makingrotorrpmadjustmentandne-tuningmoredicult.
CCPM SERVO CENTERING WITH THE SUB-TRIM FUNCTION
Itmaybenecessarytomakeminorservocenteringadjustmentswiththeuseofthesub-trimfunctiontoachievethe
desiredservoarmpositions.Adjustthesub-trimpercentagesthroughtheradiosystemasnecessarytomakethe
servowheelscenterproperly.Withproperservoarmpositioning,littletonosubtrimwillberequired.
PITCH-TO-AILERON MIXING ADJUSTMENT WITH TRAVEL ADJUST
It is very possible that the travel of each servo varies slightly, which can cause the swashplate to be tilted to the
left or right when the collective is moved to the extreme high and
low pitch positions. This condition is generally more common when
standard-type servos are used. If JR® digital servos are used, the
adjustmentrequiredisgenerallyverysmall,ifany.Thesevariations
in travel can be corrected by altering the travel value of each servo
slightlythroughthetraveladjustmentfunction.Tocheckthepitch-
to-aileron mixing, it will rst be necessary to position the collective
stick in the center position and make sure the swashplate is level.
Next, move the collective stick from the center position to the high
pitch position while viewing the swashplate from the rear of the
model as shown in the diagram below. While moving the swashplate,
look for any tendency for the swashplate to roll to the left or right
as it reaches the high pitch position. Repeat this procedure several
times to be sure that your observations are correct. If no rolling tendency is found, it will now be necessary to repeat
this procedure from the center collective stick position to full low pitch. If no rolling tendency is found, proceed to
the next step.
In our example, we have shown that the swashplate has been tilted to the left as the collective has been increased
to full pitch. This would indicate that the left servo’s maximum travel is less than the right servo’s maximum travel.
In this condition, we suggest that the travel value for the left servo be increased slightly (5–10%). Repeat the
procedure above if the same condition occurs, but to a lesser degree. The travel value of the right servo should be
decreasedslightlyandretested.Inmostcases,itwillrequireonlytheadjustmentoftheleftorrightservotocorrect
this situation. Once this condition has been corrected, repeat this procedure for the center-to-low collective pitch
positionandadjustasneeded.