Hello guys,few days ago I bought a HK digital servo and it's not working when I connected it to my rx.It's strange to me because I used to have an analog servo,which works perfectly.My digital servo works only if I connect it to my flight controller.And I never even understood the difference between analog and digital terms in class.

Hello man.
Read your strange account with the servos but its very simple to understand the difference. Both the types- analog as well as digital work on the same principle- reading position and maintaining the command position from the rx. The only difference between the two is how many times the correction is sent to the motor, meaning while in analog servo the correcting pulses are sent 50 times a second, digital servos do it at about 300 seconds. This results in a better hold position and lesser glitch under a given load.

As far compatibility goes, almost all servos have the same connections and voltage and logic parameters. So if an analog servo works from a given PWM source it would surely work with any other high end digital servo.

Please keep updated about your progress and post any additional information in this regard. Have a nice day!