Operation Manual

How suppression
works
The transmitter
generates
a
"suppress"
signal
which is
proportional
to the
tail rotor stick
position
(regardless
of
the direction
of
movement). This signal
is transferred to
the
"sensitivity
input" of the
gyro
via a separate
chan-
nel. The
further the stick
is moved, the more the sensF
tivity of the
gyro
is reduced; the
less sensitive
it
becomes.
the
less
effect
it has, and the
more the model
resoonds
to deliberate control
movements.
This
effect
is
represented
in Fig. 40. Fig.
40
a shows
the suppression
signal,
40 b the
corresponding
gyro
effect.
Fio.40 b
The
gyro
usually
has two adjustors
which are used
to
set
top and bottom
limits on
the sensitivity
range.
At the lransmitter
end a slider
or a switch can be
used
to control
"GYRO".
lf a slider
is used,
it becomes
possible
to adiust
"gyro
suppression"
steplessly
(not
to be confused
with
infi-
nitely
adjustable
suppression,
which is
proportional
to
stick
movement!).
In this case the
range of adjustment
is within
the limits set
on the
gyro
itself. Using a switch,
on the
other hand,
you
can
"only"
switch
between the
two
limits set on the
gyro.
In
practice,
this latter
facility
has
proved
to be
quite
adequate;
an
inlinitely adiustable
setting
is really one thing
too many
for most
pilots
to
cooe
with. Please
read the note at
lhe end of this
sec-
tion
in
this
connection.
The system
in
practice
We will suppose, as an
example,
that
you
have
assigned
"transmitter
control
H
=
GYRO"
and
"Servo
No. 6 controls
GYRO", as already
described.
As switch
lor the Gyro function
you
can use either
a
2-oosition
switch
with 2-core lead, or a 3-position
switch
with 3-core
lead. To be able
to exploit the
full
control
travel when
you
are using
a switch
with
a
2-core lead a
value of 1000/o must be set at
the
"Centre"
option.
Now all
that is left is to switch
automatic suppression
on.
Move
to
the
"Transmitter
Control
Options"
menu
and leaf through
to control H.
Press
N
and
the
El
and
E
keys to select
"AUTO".
You
will see this display:
rH:
tj'T'Fjt:t
HUT|_].
I
:;I-IFF'F:E:;:;:
üFF
r
Press the
A
key, then
E
.
"OFF"
is replaced by
"ON";
and that's
it.
.
Tip:
-
Connect a servo
(instead
of a
gyro)
lo the receiver
"GY-
RO" output
for this setting up
process.
You will then be
able to see
exactly how the suppression
effect
works.
With switch
H
set
to
OFF
and the tail
rotor stick at cen-
Fio.40 a
tre, the servo
will be at one end-point.
lf
you
now
oper'
-
ate
the stick, the servo
will run towards
the other end-
point,
its movement
proportional
to the stick
position;
regardless
ol which side the stick
is moved to.
lf
you
now set switch
H to ON, the servo
runs
straight
to
this end-point,
and is not affected
by movement ol
the
stick:
it receives the signal
"gyro
fully suppressed".
lf necessary:
Depending
on
your
particular gyro,
it may turn out that
the
suppression
works
"the
wrong way round";
i.e.
when the tail
rotor stick is at centre,
suppression
is at a
maximum, and
it reduces as stick
detlection
increases.
In this case
you
need to
move to the
"
Servo
adiust-
ment"
menu. Select
"TRAVEL
+
REVERSE" and leal
through
until
you
reach
"Servo"
No. 6. Press the
Sl
key, then
E.
You have
now
"
reversed"
gyro
suppres-
sron.
Supplementary
notes
1. Minimum
and maximum suooression
During
this description
we have assumed
that the
"cor-
ner values"
for
suppression
(maximum
and minimum
suppression),
between
which
you
can move using
the
switch
H, were set on the
gyro
itself, as explained
at the
beginning
of the section.
lf the
gyro
does
not otfer this
feature, or
you
want to
carry
it
out at
the transmitter,
then there
is
an alternative
method:
Move
to the
"Servo
adjustment"
menu, select
'TRAVEL
+
REVERSE", and set the
"travel"
of
gyro
suppression
as
you
wish.
When
you
adjust the
travel
(you
can do it separately
for both directions!),
all
you
are
doing
is
selting
the corner
values for
gyro
suppression
(see
Fig. 41).
o
+
59