GRAUPNER mx-12 Hott Programming Manual Download

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100

Program description: transmitter control settings – model helicopter

input

output

point

+50%

ch1

thr

Note:
Since the throttle trim lever has no effect when the throt-
tle limiter is open, its position is not relevant at this point.

Now - without starting the glow motor - adjust the
mechanical linkage of the throttle servo so that the
carburettor barrel is fully open; if necessary, carry out
fine-tuning using the travel setting for servo 6 in the
“

Servo settings

” menu.

Close the throttle limiter completely by turning the rotary
proportional knob CTRL 6 anti-clockwise to its end-
point. Use the trim lever of the throttle / collective pitch
stick to move the trim position marker to the motor OFF
position (see illustration in the right-hand column of the
next page).

Note:
In contrast, when the throttle limiter is closed, the posi-
tion of the throttle / collective pitch stick is not relevant;
it can therefore be left in the maximum collective pitch
position, i. e. the throttle linkage can be adjusted be-
tween full-throttle (throttle limiter open) and “motor OFF”
(throttle limiter closed) using just the throttle limiter.

Now, with the throttle limiter closed, adjust the mechani-
cal throttle linkage so that the carburettor is just fully
closed. However, do check carefully that the throttle
servo is not stalled at either of its extreme end-points
(full-throttle / motor OFF).

stop

flt

CTRL 6

Current trim position

Trim at motor OFF position

Last idle position

Throttle limit control

For this reason the Ch 1 trim display is also completely
suppressed as soon as the throttle limit control is moved
to the right of the centre position.

stop

flt

CTRL 6

Throttle limit control

Note:
Since this trim function is only effective in the “Motor
off” direction, the illustration above changes if you alter
the transmitter control direction for the collective pitch
minimum position of the Ch 1 stick from “back” (reflected
in the picture above) to “forward” in the “Collective pitch
min.” line of the “

Base settings

” menu. In the same

way the effects shown in the illustration swap sides if
you change the stick mode from collective pitch right
(reflected in the pictures above) to collective pitch left in
the “Stick mode” line of the “

Base settings

” menu; see

page 82.

To complete this basic set-up you still have to adjust the
idle trim range to coincide with point “1” of the throttle
curve. This is accomplished by setting point “1” of the
“Ch 1



throttle” mixer in the “

Heli mixer

” menu to a

value of about +15 to +18%:

input

output

point

+16%

ch1

thr

To check that the setting is

exact

, i. e. that there is a

seamless transition from idle trim to the throttle curve,
you need to close the throttle limiter and move the
collective pitch stick to and fro slightly at the minimum
end-point. When you do this, the throttle servo must not
move! In any case fine-tuning must be carried out with
the model flying.
The motor is always started with the throttle limiter
completely closed; this has the effect that the idle speed
is adjusted solely using the trim lever of the throttle /
collective pitch stick.

Throttle limit in conjunction with the digital trim

When used with the throttle limit control CTRL 6, the
Ch 1 trim places a marker at the set idle position of the
motor; at this point the motor can be stopped using the
trim. If the trim is in its

end-range

(see screen-shot: top

picture in the right-hand column), then a single click
immediately takes you back to the marker, i. e. to the
pre-set idle position (see also page 58).
The cut-off trim only acts as idle trim in the

left-hand half

of the travel of the throttle limit control, i. e. the marker is
only set and stored within this range.