I have servo problem

[arash]

Hi guys.
I have a problem on SERVO MOTOR Driving.It has 4 wire.one red ,one blue and tow yello .I conect red to +5 and blue to 0 but the motor turn quickly and the yello wires don't have any affect .in proteus it works good but not in real .Here is my project with "proton" and the servo specification
   
    Nakamichi
    FG-SERVO
    MHX-8B2RSN

[sfiga69]

I have the doubt that is not a servo standard. the servo standard for fly/car/boat model have 3 wire: black red and wite or yellow. which type model is your servo? proteus simulate this type of servo (pwm 1ms to 2ms to rotate fully cw to ccw)

[joker12]

FG Servo  Drive

Frequency Generator Servos or Tachometers, offer the most sensitive way to control a DC drive system. The Tachometer provides a direct readout of motor speed and thus is able to control the motor most effectively. This drive system offers the best control of both long term speed drift and static stylus drag friction. It cannot however respond fast enough to dynamic groove friction. But if the platter is heavy enough, the flywheel effect will deal effectively with most dynamic groove friction effects.

Normally it would be driven by a Phase locked loop circuit

This is not the same type of servo that is used on hobby servos.

[arash]

Thank you guys for your help.Do you know where can i finde the datasheet for this servo.