Digital vs Analog Servos

[John Wagg]

I bought some mini digital servos by mistake (par for the course these days ) and they "buzz" a lot. As soon a you touch a stick, and sometimes just on their own, they want to move and the buzz is quite noisy. Is this normal or am I operating them wrongly?

Set up is a FRSKY Taranis Q X7 tx, various receivers and 4.8v Ni'Mh supply. 

Edited May 9, 2021 by John Wagg

[Philip Lewis 3]

No that is quite normal for some digital servo's, some do some don't but in my experience most do, if they buzz at a standstill moving the stick ever so slightly might silence them but it's very common especially with a tight dead band.

[Martin_K]

John, a digital servo sends power pulses to the servo's motor at a higher frequency than an analog servo. This digital servo motor control pulse rate (frequency) is distinct from the frequency of the PWM control signal from the receiver to the servo.

 

As Philip says, hearing the buzz is normal, it is likely to be in your comfortable audible frequency range.

[Neil James]

My experience with buzzing digital servos is that the buzzing is significantly reduced when the faster 10ms setting is selected instead of 20ms. I’ve noticed this on a few models and now buzzing is a reminder to me to get into the receiver setup and change the setting.

[Tim Ballinger]

15 hours ago, Neil James said:

My experience with buzzing digital servos is that the buzzing is significantly reduced when the faster 10ms setting is selected instead of 20ms.

Interesting Neil, I was fairly convinced about that characteristic as well so I follow the same practice. 
 

Tim