RCTIME, Value Drift, And Pelicans

Archiver

Hello,

I have a stamp 2sx with 8 10k pots and .1 mf caps in a rctime circuit
on 8 different in/outs.
When changing any one of the pots, the other pots values change even
though they are on different in/outs.

Anyone know a way to isolate them from each other?

Thanks,

Ken

Archiver

>Hello,
>
>I have a stamp 2sx with 8 10k pots and .1 mf caps in a rctime circuit
>on 8 different in/outs.
>When changing any one of the pots, the other pots values change even
>though they are on different in/outs.
>
>Anyone know a way to isolate them from each other?
>
>Thanks,
>
>Ken


That's interesting...

If you have a scope or AC voltmeter, be sure the power supply is
stable. Add a capacitor if necessary. Are you using this kind of
sequence:

RCtime 0,1,x
high 0 ' set the pin
RCtime 1,1,x
high 1


Be sure that the potentiometer value is not so low that it will cause
an effective short circuit between the power supply and the stamp pin
when the pin is an output. Add a ~1k ohm resistor if necessary
between the junction of the 10k/0.1uf and the pin.

The RCtime command has some natural error sources from drift and
noise and self-heating:
http://www.emesystems.com/BS2rct.htm#drift:

-- regards,
Tracy Allen
electronically monitored ecosystems
mailto:tracy@e...
http://www.emesystems.com