Servo weirdness
mpark
Posts: 1,305
I have a servo plugged into a Propeller Demo board and there's something weird going on. I don't think it's Propeller-related because it happens even with the Demo board turned off(!)
What happens is this: if I touch a piece of metal (such as a washer held in my hand) to the metal part of the Demo board's VGA jack, the servo turns a little. Just a little turn, but always in the same direction, so if I keep tapping, the servo keeps turning (it's been modified for continuous rotation).
I have power from a wall wart split into two branches, one going to the servo, the other to the Demo board's power jack. The servo's input pin is connected to a Prop pin, but as I said, the Prop doesn't even have to be on for the mystery behavior to manifest.
Any ideas as to cause or solution?
What happens is this: if I touch a piece of metal (such as a washer held in my hand) to the metal part of the Demo board's VGA jack, the servo turns a little. Just a little turn, but always in the same direction, so if I keep tapping, the servo keeps turning (it's been modified for continuous rotation).
I have power from a wall wart split into two branches, one going to the servo, the other to the Demo board's power jack. The servo's input pin is connected to a Prop pin, but as I said, the Prop doesn't even have to be on for the mystery behavior to manifest.
Any ideas as to cause or solution?
Comments
An alternative is that the short condition is creating a transient pulse that the servo responses to. Another alternative is that you are providing static electricity when you contact the board - not a good practice.
You might just insulate the parts that cause the offending condition.