Servo from starter kit hums, heats up

Attached the servo from the starter kit like so:

brown lead: GND
red lead: VIN
yellow lead: A7

it works when I move it around with the tinker app, but it hums even when it isn’t moving and is getting pretty warm. Is this to be expected?

Sponge file, does it hum and get warm if you disconnect the A7 line?

Hi @spongefile

It sounds like you have it hooked up right–I have a picture in a tutorial here:

Another good question is: How are you supplying power to the core + servo? I have had a problem when I had two servos (one big, one small) on a cell-phone power supply–they make humming noises when moving, and move in a very jerky way.

Servos are electo-mechanical and sometimes inertia and friction work against you. If I command my little servo to certain positions, it will hum (quietly) and jitter slightly as the feedback loop in the servo tries to hit that exact angle, but it doesn’t seem to settle down perfectly. If I command it to move +/- a few degrees, it settles down.

Hum stops when A7 is disconnected.
Core is powered via USB from my laptop.
Hum also stops when I set tinker app analogWrite to either 0 or 255. Hum happens at every step in between.

Hi @spongefile

OK, Tinker is not setup to drive servos. You want to use myservo.write(position).

You don’t want to use analogWrite() with a servo, since I think the timing will be off.

If you look at the sketch in my tutorial here, they are easy to drive:

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Ok, excellent! Thanks!

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