AVR-Chat

>
>    Could you post the schematic and program snippet that you used ? When I
>tried to use the ADC it seemed to be very bad. I probably made something
>quite wrong but did not have the time and incentive ($$) to find out what it
>was...

There are some timings to be observed, for when you can change channels.
What I did, was to launch the conversion in the foreground, with the conversion complete ISR storing the data.

I did one system with rotating channels, automatically sampled by the conversion complete ISR, but most of my apps lately, need the samples taken at specific times, so I can't use that approach..

This may also be a factor, if your input is noisy you can have aliasing problems.

Filter the input as much as you can. No sense letting the input change faster than you can sample.