GRAUPNER mx-12 Hott, Programming Manual

Page: 136 / 200

136
Program description: Fail-Safe
FAIL SAFE
Pos
hold
1 2 3 4 5 6 7 8
Delay 0.25s STO
The inherently higher operational security of the HoTT
system compared with classic PPM technology is due
to the ability of the HoTT receiver’s integral micro-proc-
essor to process the signals from “its” transmitter ex-
clusively, and also to process any “dirty” control signals
which it picks up. The receiver constantly stores the
latest valid signals, and invalid signals are automatically
replaced by the stored signals - but only if the control
signal is seriously inaccurate or even damaged, e. g. due
to interference from an outside source. This process is
dependent upon various settings which are described
later in this section. For example, the receiver sup-
presses brief interference such as field strength “holes”
and similar effects which would otherwise result in the
familiar “glitches”. When this happens, the red LED on
the receiver lights up.
If you have not yet programmed any Fail-Safe settings
in the currently active model memory, the following
warning display will appear in the basic display for a few
seconds when you switch the transmitter on:
fail safe
setup
t.b.d
Programming
The “Fail-Safe” function determines the receiver’s beha-
viour when interference occurs in the transmission from
transmitter to receiver. The receiver outputs 1 … 8 can
optionally …
maintain (“hold”) their current position: 1.
If interference should occur, all servos programmed
to “hold” mode remain at the position last assessed
by the receiver as correct until such time as a new,
correct control signal arrives at the receiver, or
move to a user-selectable position (“Pos”) if interfer-
2.
ence occurs, after a “delay” time has elapsed.
Use the arrow buttons

of the left or right-hand
touch-key to select the desired servo socket 1 to 8 (

),
then touch the central SET button of the right-hand
touch-key to switch between “hold” ( ) and “position” ( )
mode:
FAIL SAFE
Pos
1 2 3 4 5 6 7 8
STO
hold
Delay 0.25s
Now select the “Delay” option at bottom left of the
screen using the arrow buttons
 of the left or right-
hand touch-key …
FAIL SAFE
Pos
1 2 3 4 5 6 7 8
STO
hold
Delay 0.25s
… touch the central
SET
button of the right-hand touch-
key, and use its arrow buttons to select your preferred
delay period from the four on offer (0.25 s, 0.5 s, 0.75 s
and 1 s).
Simultaneously pressing the arrow buttons
 or 
of the right-hand touch-key ( CLEAR ) resets the high-
lighted field to the default value of 0.75 s.
Now use the arrow buttons
 of the left or right-hand
touch-key to select the STO field at bottom right of the
screen; SIMULTANEOUSLY move the servos for which
you have selected Position mode to the desired posi-
tions using the associated transmitter controls.
A touch of the central
SET button of the right-hand
touch-key stores these positions in the receiver as the
Fail-Safe settings, so that it can revert to these if interfer-
ence should strike.
The transmitter informs you of the stored data by briefly
displaying:
FAIL SAFE
Pos
1 2 3 4 5 6 7 8
STO
Position
stored
hold
Delay 0.25s
Caution:
We strongly recommend that you make use of the
safety potential of this option by at least setting the
throttle position (glow-powered models) to idle, or
the electric motor to stop, if a fail-safe event should
be triggered. Model helicopters should be pro-
grammed to “hold”. This simple precaution ensures
that the model is much less likely to cause havoc
and cause property damage or personal injury.
Fail-Safe