RC servos are composed of an electric motor mechanically linked to a potentiometer. Pulse-width modulation (PWM) signals sent to the servo are translated into position commands by electronics inside the servo. When the servo is commanded to rotate, the motor is powered until the potentiometer reaches the value corresponding to the commanded position.
The servo is controlled by three wires: ground (usually black/orange), power (red) and control (brown/other colour). The servo will move based on the pulses sent over the control wire, which set the angle of the actuator arm. The servo expects a pulse every 20 ms in order to gain correct information about the angle. The width of the servo pulse dictates the range of the servo's angular motion.
A servo pulse of 1.5 ms width will set the servo to its "neutral" position, or 90°. For example a servo pulse of 1.25 ms could set the servo to 0° and a pulse of 1.75 ms could set the servo to 180°. The physical limits and timings of the servo hardware varies between brands and models, but a general servo's angular motion will travel somewhere in the range of 180° - 210° and the neutral position is almost always at 1.5 ms.
FUTABA S3153 - Tail Servo
This is the S3153 Digital High Speed Micro Mini Servo Designed for use with Futaba Radio Control Systems. This Servo is the Digital High Speed version of the S3103 Servo.
This servo can produce high-current draw from your batteries. If using NiMH or LiPo batteries, make sure they are capable of delivering sufficient amps.
Spec:
Torque: 19 oz-in @ 4.8V, 24 oz-in @ 6V
Speed: 0.13 sec/60° @ 4.8V, 0.11 sec/60° @ 6V
Size: 0.9 x 0.4 x 0.8" (22 x 11 x 20mm)
Weight: 0.38oz (9.6g)
Lead Length: 6.7" (170mm)
COMMENTS: Do not use this servo with gasoline powered Helicopters requiring high torque.
FUTABA S9257 Servo
This is the Futaba S9257 High Speed Digital Servo for Helicopter Gyro Operation, ideal for the Align Trex 500
Spec:
Dimensions: 1.4 x 0.6 x 1.1" (36 x 15 x 29mm)
Weight: .92oz (26g)
Torque: 28 oz-in (2.0 kg-cm) at 4.8V
Operating Speed: 0.08 sec/60° at 4.8V
Lead Length: 7.9" (200mm)
For use with the Futaba GY401 (FUTM0807, FUTM0808) and the GY502 gyros, Equipped with two ball bearings.
Futaba S9650 Servo
This is the Futaba S9650 Digital Mini Servo with two ball bearings for helicopter and airplane use and comes with "J" connector pre-installed. Precision helicopter flying requires precise, high-tech servos, and it answers the call with new digital servos that reach full power immediately. It features high-capacity, high-current wire for low resistance while maintaining standard servo dimensions and light weight so you can mount them almost anywhere.
This is a High Torque, High Speed Digital Mini Servo from Futaba. Coreless motor, conventional servo motors have a steel core armature wrapped with wire that spins inside magnets. In a coreless design the armature uses a wire mesh that forms a cup that spins around the outside of a magnet. This arrangement is much lighter, which results in smoother operation and faster response time.
Spec:
Dimensions: 1.4 x 0.6 x 1.1" (36 x 15 x 29mm)
Weight: .92oz (26g)
SPEED: 0.14 sec/60° @ 4.8V
0.11 sec/60° @ 6.0V
TORQUE: 50 oz-in (3.6 kg/cm) @ 4.8V
63 oz-in (4.5 kg/cm) @ 6.0V
HITEC HS-5065MG Servo
Hitec just raised the bar by offering the ever popular HS-65 in a new digital version! The HS-5065MG High Performance Micro Servo features Hitec's digital, programmable circuit for incredible resolution, centering and holding torque; also featuring metal gears, a top-ball bearing, and at 31 ounces/inches of torque with a quick transit time of 0.11 sec at 6 volts, it will no doubt be the choice for high performance micro helicopters.
Spec:
Speed: .11 sec/60° @ 4.8V
.09 sec/60° @ 6V
Torque: 19 oz-in (1.4kg/cm) @ 4.8V
24 oz-in (1.7kg/cm) @ 6V
Dimensions: .9" x 0.4" x 0.8" (22 x 11 x 20mm)
Weight: .34oz (9.6g)
Output Shaft Diameter: 5mm
| Futaba S9257 Digital ServoT-rex 450 | |
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Additional links to more information
Top 10 Remote Control Helicopters
Fuselage | Define Fuselage at Dictionary.com
Is a RC helicopter good or a RC car? - Yahoo! Answers India
BBC - Leicester - Secret Level - Maximo Vs The Army Of Zin reviewed
Syma S107 RC Helicopter Deals
X Heli RC Helicopters