Futaba 5NLH FM - Manual (Page 5)

• General adjustment
Make the linkages and adjustments as described in the model manu-
facturer's instruction manual.
When the throttle (engine control) stick is set from the SLOW side to
the HIGH side, the throttle servo operates as shown in Fig. 14A. If
revolution mixing is applied at this time, the rudder servo operates
together with the throttle servo as shown in Fig. 14B. This operating
width is called the mixing amount. The rudder stick operating width
becomes larger as the number of divisions of the scale become larger.
The rudder servo is operated as shown in Fig. 14B at right rudder stick.
However, if the throttle (engine control) stick is at SLOW, the neutral
position is from the left and if the throttle (engine control) stick is at
HIGH, the neutral position is from the right.
Throttle stick
neutral position
HIGH
Up side
mixing amount
B. Rudder
servo
A. Throttle
servo
SLOW Right Left
• Revolution mixing adjustment
When the main rotor rotates, the helicopter attempts to turn in the
opposite direction. To cancel this torque reaction, the pitch of the tail
rotor (rudder) is increased. Revolution mixing performs this operation
simu.ltaneously with the throttle (engine control), and is necessary to
fly a helicopter. (If used with a rate gyro, operation is much easier.)
When main rotor rotates
clockwise.
Tail rotor pitch is increased
so that the helicopter does
not turn to the left.
2 Helicopter turns to the left.
1 Check the direction of operation of each servo. To reverse the
direction of operation, switch the reverse switch.
2 Always set the idle up switch and throttle hold switch to
OFF (pushed to the opposite side).
3 Make the basic adjustments described by the model helicopter
manufacturer.
4 Check the left and right (up and down) throw of each servo. If the
throw is incorrect, correct it by changing the position of the servo
horn hole, etc.
5 Set the throttle stick to about the center (medium slow) and
Down side
mixing amount
Fig. 14
Fig. 15
12 If the helicopter turns to the left during hovering, turn the revolu-
tion mixing up side knob clockwise. If the helicopter turns to the
right, turn the knob counterclockwise.
13 Rate gyro output adjustment (when FP-G153 used)
A position about 40% to 80% of the rate gyro control box scale
should be sufficient. (Differs somewhat with the model.)
If the tail of the helicopter whips back and forth, the gyro output
should be increased.
• Idle up adjustment
When the idle up switch is OFF, the throttle servo operates normally as
shown in Fig. 16A. When the switch is ON, when the idle up trimmer is
suitably set, the throttle servo changes to the maximum slow position
as shown in Fig. 16B.
When idle up is used, hovering is stable and the rotor speed can be held
even when the pitch is reduced during rolls and prettier maneuvers are
possible.
1 Set the transmitter throttle (engine control) stick to maximum slow
and set the idle up switch to ON and set the idle up trimmer to
about 20 to 25%.
2 Next, set the idle up switch to OFF, start the engine, hover, and
decide the speed at hovering. Set the idle up switch to ON, hover,
and adjust the idle up trimmer so that the speed is about the same
as, or somewhat slower than, that when the idle up switch is OFF.
When the idle up trimmer is turned clockwise, the speed increases.
When starting the engine and after use, always set the idle up switch
to OFF.
SLOW
HIGH SLOW
A. Throttle
servo
B. Throttle
servo
• Aileron and elevator AST (Adjustable Servo Throw)
The servo throw is changed within the
range shown by the hatched lines in Fig.
17 with the aileron & elevator AST trim-
mer. The throw can be adjusted from a
maximum 100% to a minimum 40% by
turning each trimmer with a flat blade
screwdriver. Set to the throw matched to
the model.
• Throttle hold adjustment
HIGH
Fig. 16
Fig. 17
install and link the servo horn at the neutral position.
6 Set the revolution mixing up side knob to about divisor 5 and
revolution mixing down side knob to about divisor 7.
7 Check the engine throttle linkage.
• Throttle opened fully at throttle stick HIGH (up).
Throttle closed fully at throttle MAXIMUM SLOW (down).
• Use ATL (Adjustable Throttle Limiter) trimming as much as pos-
sible.
This is convenient because the HIGH side does not change even if the
LOW side is changed. Then set the throttle stick to its full operating
width and set so that the pitch control servo operates over its maxi-
mum throw.
Regarding the main rotor variation width, select the servo horn
position as specified by the model manufacturer.
8 After starting the engine and adjusting the needle, hover and adjust
the aileron and elevator trim. Next, make the main rotor pitch at
hovering somewhat large with the linkage.
9 Adjust the linkage so that the rudder trim is neutral at hovering.
10 After adjusting all the trim levers, adjust revolution mixing.
11 If the helicopter turns to the right during hovering after lift off,
turn the revolution mixing down side knob clockwise. If the
helicopter turns to the left, turn the knob counterclockwise.
When the throttle hold switch is pulled on, the throttle servo stops at
the position set with the throttle trimmer. Trimmer scale division 0 is
maximum slow. Setting to the high side is possible as the number of
divisions increases. When the switch is OFF, the throttle servo is con-
trolled by the transmitter throttle (engine control) stick. T his device is
used at auto rotation take off. After the engine is cut or at maximum
slow (during practice), only the pitch control servo is operated (pick
up) and safe take off is possible.
1 Set the throttle (engine control), throttle (engine control) switch
and throttle (engine control) trimmer so that the engine throttle is
fully closed at maximum slow.
2 Set the throttle trimmer so that the engine throttle becomes maxi-
mum slow when the throttle hold switch is set to ON (pulled for-
ward) at autorotation practice. (Set so that the throttle is fully
closed when the engine is cut.)
3 When the throttle hold switch is set to OFF (pushed back), the
throttle (engine control) servo and pitch control servo mixing is
performed. When the switch is set to ON, the throttle servo is held
(maximum slow set by the throttle trimmer or fully closed) and
only the pitch control servo operates.
4 When the hold switch is used at take off, etc., always hold switch
to OFF after setting the transmitter throttle stick to slow. Also,
before starting the engine, check if the idle up switch and throttle
hold switch are OFF.