bad encoder ?

[nlecaude]

Hello, I just digged up this encoder: https://www.sparkfun.com/products/10982 that I bought a couple months ago.
I'm trying it with a Teensy 3.1 using the Encoder library via the basic examples.

When I spin the encoder slowly it seems to work great but if I try to spin it moderately fast I get erratic results, for example, instead of getting a continious steam like this:
120
121
122
123
124
I get something like this:
120
121
120
121
122
121
122
123

It will increment and decrement but with duplicates.
I tried another encoder I have, an alps one and that one seems to work flawlessly with the same setup.
So I assume this particular encoder is a piece of junk ?

 

[PaulStoffregen]

Looks like it's working, but with some mechanical chatter.

The real question is whether it's always ending up with the right count when you stop at any particular angle?

 

[Macona]

You have to debounce the signal, those encoders have mechanical contacts. Look at page 4 of their data sheet, they mention about chatter.

 

[nlecaude]

I assume that if I want to use the Encoder library it would be best to do the debouncing in hardware ?

 

[Macona]

I would give that a try first. Look at the comments on spark fun's page for the encoder, lots of other people have similar problems.