User manual

92
Program description - Base setup models | Winged models
doing so, simulate all servo movements which also
take place during flight. The range must always be
at 50 m on the ground in order to assure safe mod-
el operation.
Caution:
Never start the range test on the transmitter dur-
ing normal operation of the model.
DSC output
If necessary, use the  selection keys of the left or
right four-way button to switch to the “DSC Output”
line then, with a brief tap on the center SET key of the
right four-way button, activate the value window:
SEL
Rcv Ch Map R12
R08
Base setup model
RF transmit ON
RF Range Test 99sec
DSC Output PPM10
Now you can use the right selection keys to choose
between four types of modulation “PPM10”, “PPM16”,
“PPM18” and “PPM24”. Touch the center SET key of
the right four-way button again to complete the entry.
This choice primarily influences the maximum num-
ber of control channels which can be attached to the
DSC (direct servo control) socket, and thus also avail-
able to a flight simulator or teacher/pupil system. By
selecting “PPM10” this will be control channels 1 … 5,
for “PPM16” channels 1 … 8, for “PPM18” channels 1
… 9 and for “PPM24” channels 1 … 12.
Cut off
Note:
This menu line is suppressed if “None” or “None/inv”
is selected for the “Motor on C1” line.
Depending on the “idle forward or back” choice made
in the “Motor on C1” line of the »Model type« menu,
this motor “cut off” option can be coupled to a switch
for throttling down a speed controller or to move a
servo on the carburetor of a motor to the OFF posi-
tion. This option can be used on the
mc-16 HoTT
and mc-20 HoTT transmitters as an emergency
OFF function as well as an alternative “cut-off trim”,
see “digital trims” on page 70.
This motor OFF position (Thr. CutOff) is specified in
the left column field over the column label SEL and its
value is to be established through trial and error.
However, the speed controller or throttle servo only
moves to the selected position when two conditions
are fulfilled: a switch is operated, and a particular
servo position or switching threshold is exceeded.
This is done by setting the desired servo position
(threshold value) into the middle column field, directly
over the column label STO, then selecting the appro-
priate ON/OFF switch function in the right column.
• If the percentage value specified for the middle
column is greater than the current servo posi-
tion, i. e. the current servo position lies below the
threshold, the switchover will occur as soon as the
switch is put into its ON position.
• If the percentage value specified for the middle
column is less than the current servo position, i. e.
the current servo position is above the threshold,
the speed controller will initially reduce motor
speed or close the carburetor’s throttle servo only
to the extent dictated by the value in the left col-
umn as soon as the servo’s position once under-
runs the threshold (max. +150 %) after the switch
is changed over to its ON position.
The speed controller or throttle servo will remain in
this cut-off position only until the selected switch is
again changed over followed by a one-time throttle
servo or speed controller movement beyond the
preset threshold with the throttle/brake stick con-
trol.
The factory setting for the left column is -100 % for
the throttle servo “cut-off” position and a threshold of
+150 % servo position setting in the middle column.
Base setup model
RF transmit ON
RF Range Test 99sec
DSC Output PPM10
cut off
SEL
–––
+150%
STO
–100%
Programming procedure
To change the throttle servo’s preset “cut-off” posi-
tion, tap on the center SET key of the right four-way
button. The current setting will be displayed in inverse
video. Now use the selection keys of the left or right
four-way button to set a value at which the motor is
reliably “off”. If a combustion motor is involved, be
sure the throttle servo does not perform mechanical
runout, e. g. -125 %:
Base setup model
RF transmit ON
RF Range Test 99sec
DSC Output PPM10
cut off
SEL
–––
+150%
STO
–125%
The – upper – preset value in the middle column
ensures the motor can be stopped, throughout the
maximum possible positioning range of the servo or
speed controller, alone by the switch to be assigned
in the right column.
However, if you wish to set a lower threshold, by
which an underrun will cause the throttle servo or
speed controller with closed switch to switch into the
cut-off position, reduce the preset servo travel from
+150 % by placing the throttle servo or speed control-
ler into the desired position with the throttle/brake
stick then touch the center SET key of the right four-
way button.