User Manual

FEATURES
Standard Mode
While in standard mode, this gyro behaves as a regular yaw
damping gyro by sensing motion about the axis which it controls
(the yaw axis for your helicopter). The electronic components in
the gyro send a signal to your servo instructing it to steer the tail
in the opposite direction, thus preventing unwanted rotation of the
tail. The result is a much more stable tail and a helicopter that is
easier to control! In this mode, the gyro does not return the model
to its starting position.
Heading-Hold Mode
In this setting the gyro will hold the tail in the position determined
by the last input of your control stick, until a new stick command is
given. You can virtually fly the tail rotor hands-off! This is
especially helpful during backwards flight.
SET UP YOUR HELICOPTER
Test fly and set up your helicopter so it will hover when the rudder
trim is centered, the linkages are squared and the servo will travel
the same rate to the right and to the left. If you are installing your
gyro in a new helicopter that has not yet flown, pay careful
attention to the manufacturer’s instructions on how to set up the
tail rotor system and how to connect the linkages. All linkages
must be centered, squared and symmetrical. You may set the
ATV’s as required but try to get your linkage set up so your ATV’s
are as close to 100% as possible. The most important thing about
your ATV’s is that your servo cannot overdrive your rudder
linkage—make sure your servo will not push the rudder pushrod
further than your rudder linkage at the tail rotor can go.
HOOK UP THE GYRO
Hook up your gyro before you actually mount it in your helicopter.
It will be easier for you to understand its operation and perform
the necessary tests in order to make sure your gyro is set up
correctly.
❏ 1. Your gyro comes with a Futaba
®
brand “J” style connector
that plugs into your receiver. If you own a Futaba radio control
system proceed to step 3. If you own another brand of radio with
a different type of connector, you may have to modify the
connector on the gyro to match your radio, and the connector on
your servo that plugs into the gyro. Usually, all that is required is
to carefully shave the key from the gyro connector so it will fit into
your receiver and rearrange the wires so the polarities match your
radio system. In some cases, you may have to cut your servo
cord and the cord on the gyro, then solder on Futaba J-
connectors.
❏ 2. If you’ve modified your connectors, make certain the wiring
order on your servo connector and the gyro connector is the same
as the wiring order on the Futaba connector. Study the diagram.
The positive (+) wire is in the center, the negative (-) wire is on the
side opposite of the key on the connector, and signal (s) is on the
side of the connector nearest the key. WARNING! Failure to
match polarities on any connector may damage your gyro and will
void your warranty.
❏ 3. Connect the cord with the yellow band coming from the gyro
to an auxiliary channel on your receiver. This channel will be used
to switch between standard mode (non Heading-Hold mode) and
Heading-Hold mode. When in standard mode the ATV is used to
adjust the gyro’s sensitivity.
❏ 4. Connect the other cord coming from the gyro to the channel
in your receiver that operates the tail rotor servo.
❏ 5. Connect your tail rotor servo to the remaining cord coming
from the gyro.
SET UP THE GYRO
There are four different settings you must initialize before you can
use your gyro. During the setup procedures that follow, each time
you turn off the receiver switch, you must wait ten seconds
before you turn it back ON, and wait an additional ten
seconds before you give a control input from the transmitter
or move the gyro.
Set The Endpoints
The first thing we must do is tell the gyro what its endpoints are,
or how far it can drive the servo when it is in heading-hold mode.
❏ 1. Once you have connected your gyro as instructed, make
sure the four white switches on top of the gyro are in the OFF
position.
❏ 2. Turn switch #1 to the ON position.
❏ 3. Turn ON your transmitter, then the receiver. Wait ten
seconds. Move the rudder stick all the way to one side, back to
center, then all the way to the other side and back to center.
❏ 4. Turn the white switch #1 back to OFF, but do not turn OFF
your receiver or transmitter. Observe your rudder servo moving
back and forth. Now turn OFF the receiver.
Now your gyro has recorded its limits and will not travel beyond
those limits unless you perform this procedure again.
❏ 5. Turn ON your receiver and move the servo with the rudder
stick. It should operate correctly.
Note: While confirming that your rudder servo operates correctly
after you have set the limits, you may notice that the rudder servo
will reach its limits (endpoints) when the rudder stick reaches only
2/3 of its limit. This is because of the stick expander feature which
increases servo throw from the transmitter to provide better
resolution. If, after test flying, you wish to cancel this feature,
decrease your rudder ATV’s. Note that once you have set the
servo limits (by performing steps 1 - 5 above), the ATV’s will have
no effect. The servo limits can be changed only by performing
steps 1 - 5 above.
Set The Pulse Rate
Your Heading-Hold Gyro updates or sends information to the tail
rotor so rapidly (every 8ms or 12ms depending upon the position
of the #2 switch) that it provides ultra-smooth control and
operation of your heli. With the #2 switch in the ON position (this
is the 8ms selection), the gyro will provide the most optimum
performance, but this requires that you use an ultra-fast servo for
the tail rotor. For the best results in this setting, use a servo which
has a rated rotational speed of 0.11sec/60° or faster.
Do not try to use a servo with slower speed with the #2 switch in
the ON position, as the servo will not be able to keep up with the
operating speed of the gyro and could ultimately become
damaged. With the #2 switch in the OFF position (this is the 12ms
selection), the gyro can be used with normal, slower servos. With
the receiver OFF, set the #2 switch to the correct position.
Note: If, in the future, you wish to adjust the switch to work with a
faster or slower servo, you must adjust the switch with the
receiver OFF. Adjusting the switch with the radio on will not
change the setting.
Set The Gyro Mode
With switch #3 in the OFF position, the gyro will operate in
standard, non heading-hold mode at all times. With the switch in
the ON position, you are able to switch between heading-hold
mode and standard mode from your transmitter.
To switch the gyro into heading-hold mode (where you can switch
back into standard mode from the transmitter) follow the
instructions that follow.
❏ 1. Turn switch #3 on the gyro to the ON position. Turn ON your
transmitter, then your receiver. Wait ten seconds before moving
the gyro or giving an input to the transmitter.
❏ 2. Set the auxiliary switch on your transmitter so that in one
position the gyro is in standard mode, and in the other position the
gyro is in heading-hold mode. The position of the switch is up
to you.
❏ 3. Confirm that you have set your gyro correctly. With your
aux. switch in the standard gyro mode, move the gyro back and
forth and move the control stick. The gyro will behave as a
standard gyro.
❏ 4. Switch to Heading-Hold mode from your transmitter using
your aux. switch. Move the rudder control stick slowly to one side,
then return it to center. Notice that the control horn on the servo
will move with the stick to its limit, but remain even when the stick
is returned to center. This is the Heading-Hold feature. Your gyro
is holding the heading of your helicopter.
❏ 5. To set the sensitivity of your gyro while in Heading-Hold,
adjust the ATV of the side of the aux. switch that controls
Heading-Hold. Start at about 40%.
❏ 6. To adjust the holding power of the gyro while in heading-
hold mode, adjust the dynamic pot on top of the gyro with a small
Phillips screwdriver. Start at about 40%.
Note: The sensitivity and dynamic adjustment of the gyro are not
one in the same. Sensitivity adjusts how much the gyro feels.
HEADING-HOLD PIEZO GYRO
INSTRUCTIONS
Congratulations and thank you for purchasing the Heli-Max
™
Heading-Hold Piezo Gyro. A gyro stabilizes the tail rotor control on
your R/C model helicopter. Of all the controls to master, the tail
rotor is the most difficult. In fact, flying an R/C helicopter without a
gyro is nearly impossible, or extremely difficult at best. Even an
expert wouldn’t be caught without a gyro and a beginner would
probably never get off the ground without one. In addition to the
piezo crystal inside your Heading-Hold Piezo gyro, a special
feature is the Heading-Hold capability allowing your helicopter to
return to its original position predetermined by you! This is an
extremely helpful feature when learning to hover, maintaining a
steady hover or performing aerobatics that involve much
backward movement. Additionally, you may switch between
standard mode and heading-hold mode while in flight.