FUTABA GY501 User manual

1M23N04302
AVCS GYRO
GY501
INSTRUCTION MANUAL
YAW-AXIS STABILIZER FOR MODEL HELICOPTER
(RATE GYRO)

AVCS GYRO
GY501
INSTRUCTION MANUAL
YAW-AXIS STABILIZER FOR MODEL HELICOPTER
(RATE GYRO)

4
Thank you for buying a GY501 AVCS gyro.
Before using your new gyro, please read this manual thoroughly and use the
gyro properly and safely. After reading this manual, store it in a safe place.
FOREWORD
Up to now, movement of the tail from side to side due to changes in the
wind, flight posture, and other disturbances during model helicopter flights
was minimized by increasing the sensitivity of the gyro. However, a bad
effect is that the sensitivity may be increased too much so there was a limit
on how much the tail could be controlled. Changes in F3C rules add
forward and reverse flight aerobatics and demand various flight positions so
that controlling the position of the tail has become more difficult.
The GY501 gyro uses the Futaba AVCS system and makes it possible to
theoretically correct this movement. This increases stabilization of the tail
against disturbances. Since F3C contest fliers who use the GY501 gyro
together with a high response servo, of course, achieve high stability against
wind and other disturbances, it has a large effect also for helicopter novices.
•No part of this manual may be reproduced in any form without prior permission.
•The contents of this manual are subject to change without prior notice.
•This manual has been carefully written. Please write to Futaba if you feel that any
corrections or clarifications should be made.

5
FOR SAFETY
- Meaning of Special Markings-------------------------------- 6
- Setting Precautions -------------------------------------------- 7
- Operating Precautions----------------------------------------- 8
- Fuselage Maintenance Precautions-------------------------10
TABLE OF CONTENTS
BEFORE USE
- Set Contents ---------------------------------------------------11
- Name and Function of Each Part ---------------------------12
- Description of GY501 Operation ---------------------------13
ASSEMBLY AND ADJUSTMENT
- Connections ---------------------------------------------------29
- Mounting the Gyro Sensor ----------------------------------30
- Use --------------------------------------------------------------31
DATA SETTING
- LCD Display and Edit Keys---------------------------------36
- Function Map--------------------------------------------------37
- Setting of Each Function ------------------------------------38
REFERENCE
- Specifications -------------------------------------------------43
- Definition of Abbreviations ---------------------------------44
- GY501 Parameters Sheet ------------------------------------45
- Repair Service-------------------------------------------------46

6FOR SAFETY
FOR SAFETY
To ensure safe use, observe the following precautions.
Meaning of Special Markings
Pay special attention to the safety at the parts of this manual that are
indicated by the following marks.
Mark Meaning
Procedures which may lead to a dangerous
condition and cause death or serious injury to
the user if not carried out properly.
Procedures which may lead to a dangerous
condition or cause death or serious injury to
the user if not carried out properly, or proce-
dures where the probability of superficial
injury or physical damage is high.
Procedures where the possibility of serious
injury to the user is small, but there is a
danger of injury, or physical damage, if not
carried out properly.
Symbol:
; Prohibited ; Mandatory

7
FOR SAFETY
Connector Connection
Insert the connectors fully and firmly.
If vibration, etc. causes a connector to work loose during flight, the
heli may crash.
Setting Precautions
During initialization, the message **INIT* appears on the GY501
LCD screen.
Do not move the helicopter until this message disappears (in
about 5 seconds).
Also, do not move the transmitter rudder stick from the neutral
position during this period.
Precautions When Turning on the Power Switch
Always use the attached sensor tape to mount the gyro sensor.
Always reinstall the sensor tape if it has started to separate or tear.
Do not get fuel, waste oil, etc. on the gyro sensor.
The special paint may dissolve.
Sensor Mounting

8FOR SAFETY
Avoid sudden temperature changes.
Sudden temperature changes will cause the neutral position to
change. For example, in the winter, do not fly immediately after
removing the model from inside a heated car and in the summer, do
not fly immediately after removing the model from inside an air
conditioned car. Allow the model to stand for about 10 minutes and
turn on the power after the temperature inside the gyro has stabilized.
Also, if the gyro is exposed to direct sunlight or is mounted near the
engine, the temperature may change suddenly. Take suitable mea-
sures so that the gyro is not exposed to direct sunlight, etc.
Operating Precautions
At linkage
When the rudder neutral position was changed by the linkage,
the rudder neutral position in the AVCS mode must always be
re-read before use.
Re-reading method:
Turn on the transmitter in the AVCS mode, then turn on the gyro .
Or quickly switch (interval of within 1 second) the remote gain channel
switch between the AVCS mode and Normal mode at least three
times with the transmitter in the ON state. This memorizes the new
rudder position inside the GY501.

9
FOR SAFETY
Check the remaining receiver and gyro/servo nicd battery
operating time during the adjustment stage and decide how
many flights are remaining.
Never use the transmitter rudder trim in the AVCS mode.
When the rudder is trimmed during flight, the neutral position will
change.
When using the GY501 in the AVCS mode, set revolution mixing
to OFF.

10 FOR SAFETY
Fuselage Maintenance Precautions
Mounting Precautions
Use a tale rotor drive tube or other part with a high torsion
performance for the tail drive.
Take the strength of the tail into account during inspection and
adjustment.
The amount of improvement of gyro performance has a considerable
effect on the fuselage vibration level or the size, type, linkage
method, looseness, etc. of the tail rotor.
Since a higher gain than usual can be used then the tail rotor is more
effective, the load on the tail is also greater.
Always perform proper maintenance for ultimate performance.
The rigidity of the fuselage tail has a large effect on gyro perfor-
mance.
Make the fuselage vibration as small as possible.
Fuselage vibration has an adverse affect on gyro operation.

11
BEFORE USE
CONNECT
RATE GYRO
Set Contents
After unpacking the GY501 set, first check if the following parts are
provided:
BEFORE USE
Accessories: Servo horn,
mounting parts
S9205 servo (x1) (Only a set w/servo)
Sensor tape (x3)
Mini screwdriver (x1)
GY501 sensor (x1)
GY501 control amp
(x1)

12 BEFORE USE
CONNECT
RATE GYRO
GY501 control amp
Name and Function of Each Part
LCD contrast trimmer
Allows adjustment of the contrast so that the LCD display is easiest to see.
It is adjusted with the accessory mini screwdriver.
(Receiver connectors)
Remote gain input
Rudder input
Edit keys
Used when setting data.
Operated by pushing with the
accessory mini screwdriver.
(Input/output terminals)
Gyro sensor input
Rudder servo output
GY501 gyro sensor
LCD display
Displays the set data. (8 characters X 1 line)
Stick to the body using the accessory
sensor tape.
To control amp

13
BEFORE USE
Description of GY501 Operation
The GY501 gyro allows the operator to switch between the AVCS
mode (operation using AVCS function) and Normal mode (conven-
tional gyro mode) from the transmitter. Of course, the GY501 can
also be used in the AVCS mode only.
Remote Gain Function
The remote gain function lets operator perform AVCS mode and
Normal mode sensitivity adjustment and operation mode switching
from the transmitter. The channel used here is called the "remote
gain channel".
(Channel 5 is used.)
(Remote Gain Function)
Transmitter
Gain/Mode Selection
• CH5 switch
• Idle-Up switch (T8Usuper)
• Flight condition (T9Z)
Gain Settings
• ATV function
• Gyro mixing (T8Usuper/T9Z)
• Programmable mixing (T9Z)
Mode Settings
• Normal mode (NOR)
• AVCS mode (AVC)
• Selectable mode (CMT)
Gain Settings
• Gyro Gain Adjustment
GY501
Receiver
Remote Gain Channel (CH5)

14 BEFORE USE
When Using a T9Z World Champion Model Transmitter
Gyro Sense Mixing
The Gyro Sense Mixing (GYR) function lets operator perform two-point gain
adjustment at each condition. Set the sensitivity at all conditions.
[GY501 Settings]
Select the gyro operation mode at the GY501 Mode screen. (AVC, NOR, or
CMT)
[Transmitter Settings]
ATV function:
Adjust both the RATE A and RATE B rates to 100% at the transmitter ATV
function setup screen.
Gyro Sense Mixing function:
1. Select the Dual Mode (DUO) at the transmitter Gyro Sense Mixing setup
screen.
2. Set the GAIN1 and GAIN2 gains.
(The following page shows a setting example in the CMT mode.)
[Sensitivity Display]
The gain display indicates the actual gain at the GY501 G:1 and G:2 screen.
The following shows the relationship between transmitter and gyro setting
when GY501 sensitivity setting is 100% in both the G1 and G2 gain modes.
- Relationship between transmitter and gyro setting
Transmitter
settings
GY501mode
settings
Actual gain
GAIN1
GAIN2
NOR
AVC
CMT
0% - 50% - 100%
Normal mode
AVCS mode
Normal mode AVCS mode
(G2) (G1)
100% - 0% - 100%

15
BEFORE USE
GYRO SENCE
01 . MODEL-01. NORML HEL PCM 0: 23: 17
DUAL : MODE
: GAIN 1
: GAIN 2
0 20 40 60 80 100 END
85 %
15 %
85%
15%
GAIN1
setting
GAIN2
setting
70%
30%
AVCS side
Normal side
70% 40%
(Setting Example)
Adjust the gyro gain at the Gyro Sense Mixing setup screen at each
condition.
The following shows a setting example in the CMT mode.
Select the Dual Mode (DUO).
Sensitivity rate
Choose the GAIN1 or GAIN2 by the CH5 switch.
Use the following values as the sensitivity setting standard:
CH5 switch
Actual gain
Hovering Flight
The GY501 sensitivity is 0% at 50%. When set over 50%, the GY501
operates in the AVCS mode and when set under 50%, the GY501
operates in the Normal mode. When setting is changed 1%, the gyro
sensitivity is changed 2%.

16 BEFORE USE
When Using a T9Z Transmitter Programmable Mixing
The Programmable Mixing (PMX) function lets operator perform a gain
adjustment at each condition. Set the sensitivity at all conditions.
[GY501 Settings]
Select the gyro operation mode at the GY501 Mode screen. (AVC, NOR, or
CMT)
[Transmitter Settings]
Function Control:
Set the CH5 (GYR) switch to “NUL” at the transmitter Function Control
(FNC) setup screen.
ATV function:
Adjust both the RATE A and RATE B rates to 120% at the transmitter ATV
function setup screen.
Programmable Mixing function:
1. Select the “ACTIVE” mode (ACT) at the transmitter Programmable Mixing
setup screen.
2. Set the mixing type to “OFS”.
3.Set the slave channel to “GYR”.
4. Set the sensitivity rate (RATE).
(The following page shows a setting example in the CMT mode.)
[Sensitivity Display]
The gain display indicates the actual gain at the GY501 G:1 and G:2 screen.
The following shows the relationship between transmitter and gyro setting
when GY501 sensitivity setting is 100% in both the G1 and G2 gain modes.
- Relationship between transmitter and gyro setting
Transmitter
settings
GY501mode
settings
Actual gain
NOR
AVC
CMT
-100% - 0% - +100%
Normal mode
AVCS mode
Normal mode AVCS mode
(G2) (G1)
100% - 0% - 100%

17
BEFORE USE
PROG MIX 1
01 . MODEL-01. NORML HEL PCM 0: 23: 17
ACTIVE : MODE ( ON) TRIM: ******
MSTR MIX MODE: ******
: SLAVE
: MIX TYPE
LIN OFS HOV CRV CTL END
GYR
OFS
*** : MASTER
SWT
NXT
PROG MIX 1
01 . MODEL-01. NORML HEL PCM 0: 23: 17
: RATE+ 70 %
0 20 40 60 80 100 END
+70% +40%
-70% -40%
70% 40%
(Setting Example)
Adjust the gyro gain at the Programmable Mixing setup screen at each
condition. The following shows a setting example in the CMT mode.
Select the “ACTIVE”.
Select the “GYR”. Select the “OFS”.
Sensitivity rate
Use the following values as the sensitivity setting standard:
AVCS mode
Normal mode
Actual gain
Hovering Flight
When set over 0%, the GY501 operates in the AVCS mode and when
set under 0%, the GY501 operates in the Normal mode.

18 BEFORE USE
When Using a T8Usuper Transmitter
The Gyro Mixing (GYRO) function lets operator perform a gain adjustment at
each Idle-Up switch position.
[GY501 Settings]
Select the gyro operation mode at the GY501 Mode screen. (AVC, NOR, or
CMT)
[Transmitter Settings]
Gyro Mixing function:
1. Select the “ON” mode at the transmitter Gyro Mixing (GYRO) setup
screen.
2. Select the Idle-Up switch for the sensitivity selection.
3. Set the “NORM”, “IDL1” and “IDL2” gains.
(The following page shows a setting example in the CMT mode.)
[Sensitivity Display]
The gain display indicates the actual gain at the GY501 G:1 and G:2 screen.
The following shows the relationship between transmitter and gyro setting
when GY501 sensitivity setting is 100% in both the G1 and G2 gain modes.
- Relationship between transmitter and gyro setting
Transmitter
settings
GY501mode
settings
Actual gain
NORM
IDL1
IDL2
NOR
AVC
CMT
0% - 50% - 100%
Normal mode
AVCS mode
Normal mode AVCS mode
(G2) (G1)
100% - 0% - 100%

19
BEFORE USE
85%
15%
70%
30%
70% 40%
（NORM）（IDL1）（IDL2）
(Setting Example)
Adjust the gyro gain at each the Idle-Up swtch position at the Gyro Mixing
setup screen. The following shows a setting example in the CMT mode.
Select the “ON”
mode. Select the Idle-Up
switch.
Switch position Sensitivity rate
Set the “NORM”, “IDL1” and “IDL2” gains at each setup screen.
Use the following values as the sensitivity setting standard:
AVCS mode
When set over 50%, the GY501 operates in the AVCS mode and when
set under 50%, the GY501 operates in the Normal mode.
Actual gain
Hovering Flight
Normal mode

20 BEFORE USE
When Using a Transmitter ATV Function
The ATV function lets operator perform a gain adjustment at each CH5
switch position.
[GY501 Settings]
Select the gyro operation mode at the GY501 Mode screen. (AVC, NOR,
or CMT)
[Transmitter Settings]
ATV function:
Set the ATV rates at the transmitter CH5 ATV function.
[Sensitivity Display]
The gain display indicates the actual gain at the GY501 G:1 and G:2
screen.
The following shows the relationship between transmitter and gyro setting
when GY501 sensitivity setting is 100% in both the G1 and G2 gain
modes.
- Relationship between transmitter and gyro setting
Transmitter
settings
GY501mode
settings
Actual gain
ATV rates
NOR
AVC
CMT
CH5 Switch CH5 Switch
Forward side Front side
90% - 0% - 90%
Normal mode Normal mode
AVCS mode AVCS mode
Normal mode AVCS mode
(G2) (G1)
100% - 0% - 100%

21
BEFORE USE
When Using a GY501 Gyro Gain Adjustment Function
[Transmitter Settings]
Adjust both the ATV rates to 90% at the transmitter Ch5 ATV function.
[GY501 Settings]
Operation Mode Setting function:
Select the gyro operation mode at the GY501 Mode screen. (AVC, NOR, or
CMT)
Gyro Gain Adjustment function:
Set the G:1 and G:2 gains at the GY501 G:x screen.
- Relationship between transmitter and gyro setting
Transmitter
settings
GY501mode
settings
Actual gain
ATV rates
NOR
AVC
CMT
CH5 Switch CH5 Switch
Forward side Front side
90% (Fixed) 90% (Fixed)
Normal mode Normal mode
AVCS mode AVCS mode
Normal mode AVCS mode
(G2) (G1)
100% - 0% - 100%